TypeScript/src/compiler/checker.ts
2014-12-01 22:03:41 -08:00

9357 lines
492 KiB
TypeScript

/// <reference path="types.ts"/>
/// <reference path="core.ts"/>
/// <reference path="scanner.ts"/>
/// <reference path="parser.ts"/>
/// <reference path="binder.ts"/>
/// <reference path="emitter.ts"/>
module ts {
var nextSymbolId = 1;
var nextNodeId = 1;
var nextMergeId = 1;
export function getDeclarationOfKind(symbol: Symbol, kind: SyntaxKind): Declaration {
var declarations = symbol.declarations;
for (var i = 0; i < declarations.length; i++) {
var declaration = declarations[i];
if (declaration.kind === kind) {
return declaration;
}
}
return undefined;
}
export interface StringSymbolWriter extends SymbolWriter {
string(): string;
}
// Pool writers to avoid needing to allocate them for every symbol we write.
var stringWriters: StringSymbolWriter[] = [];
export function getSingleLineStringWriter(): StringSymbolWriter {
if (stringWriters.length == 0) {
var str = "";
var writeText: (text: string) => void = text => str += text;
return {
string: () => str,
writeKeyword: writeText,
writeOperator: writeText,
writePunctuation: writeText,
writeSpace: writeText,
writeStringLiteral: writeText,
writeParameter: writeText,
writeSymbol: writeText,
// Completely ignore indentation for string writers. And map newlines to
// a single space.
writeLine: () => str += " ",
increaseIndent: () => { },
decreaseIndent: () => { },
clear: () => str = "",
trackSymbol: () => { }
};
}
return stringWriters.pop();
}
/// fullTypeCheck denotes if this instance of the typechecker will be used to get semantic diagnostics.
/// If fullTypeCheck === true, then the typechecker should do every possible check to produce all errors
/// If fullTypeCheck === false, the typechecker can take shortcuts and skip checks that only produce errors.
/// NOTE: checks that somehow affect decisions being made during typechecking should be executed in both cases.
export function createTypeChecker(program: Program, fullTypeCheck: boolean): TypeChecker {
var Symbol = objectAllocator.getSymbolConstructor();
var Type = objectAllocator.getTypeConstructor();
var Signature = objectAllocator.getSignatureConstructor();
var typeCount = 0;
var emptyArray: any[] = [];
var emptySymbols: SymbolTable = {};
var compilerOptions = program.getCompilerOptions();
var checker: TypeChecker = {
getProgram: () => program,
getNodeCount: () => sum(program.getSourceFiles(), "nodeCount"),
getIdentifierCount: () => sum(program.getSourceFiles(), "identifierCount"),
getSymbolCount: () => sum(program.getSourceFiles(), "symbolCount"),
getTypeCount: () => typeCount,
isUndefinedSymbol: symbol => symbol === undefinedSymbol,
isArgumentsSymbol: symbol => symbol === argumentsSymbol,
emitFiles: invokeEmitter,
getDiagnostics,
getDeclarationDiagnostics,
getGlobalDiagnostics,
checkProgram,
getParentOfSymbol,
getNarrowedTypeOfSymbol,
getDeclaredTypeOfSymbol,
getPropertiesOfType,
getPropertyOfType,
getSignaturesOfType,
getIndexTypeOfType,
getReturnTypeOfSignature,
getSymbolsInScope,
getSymbolInfo,
getShorthandAssignmentValueSymbol,
getTypeOfNode,
typeToString,
getSymbolDisplayBuilder,
symbolToString,
getAugmentedPropertiesOfType,
getRootSymbols,
getContextualType,
getFullyQualifiedName,
getResolvedSignature,
getEnumMemberValue,
isValidPropertyAccess,
getSignatureFromDeclaration,
isImplementationOfOverload,
getAliasedSymbol: resolveImport,
hasEarlyErrors,
isEmitBlocked,
};
var undefinedSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "undefined");
var argumentsSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "arguments");
var unknownSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "unknown");
var resolvingSymbol = createSymbol(SymbolFlags.Transient, "__resolving__");
var anyType = createIntrinsicType(TypeFlags.Any, "any");
var stringType = createIntrinsicType(TypeFlags.String, "string");
var numberType = createIntrinsicType(TypeFlags.Number, "number");
var booleanType = createIntrinsicType(TypeFlags.Boolean, "boolean");
var voidType = createIntrinsicType(TypeFlags.Void, "void");
var undefinedType = createIntrinsicType(TypeFlags.Undefined, "undefined");
var nullType = createIntrinsicType(TypeFlags.Null, "null");
var unknownType = createIntrinsicType(TypeFlags.Any, "unknown");
var resolvingType = createIntrinsicType(TypeFlags.Any, "__resolving__");
var emptyObjectType = createAnonymousType(undefined, emptySymbols, emptyArray, emptyArray, undefined, undefined);
var anyFunctionType = createAnonymousType(undefined, emptySymbols, emptyArray, emptyArray, undefined, undefined);
var noConstraintType = createAnonymousType(undefined, emptySymbols, emptyArray, emptyArray, undefined, undefined);
var inferenceFailureType = createAnonymousType(undefined, emptySymbols, emptyArray, emptyArray, undefined, undefined);
var anySignature = createSignature(undefined, undefined, emptyArray, anyType, 0, false, false);
var unknownSignature = createSignature(undefined, undefined, emptyArray, unknownType, 0, false, false);
var globals: SymbolTable = {};
var globalArraySymbol: Symbol;
var globalObjectType: ObjectType;
var globalFunctionType: ObjectType;
var globalArrayType: ObjectType;
var globalStringType: ObjectType;
var globalNumberType: ObjectType;
var globalBooleanType: ObjectType;
var globalRegExpType: ObjectType;
var globalTemplateStringsArrayType: ObjectType;
var tupleTypes: Map<TupleType> = {};
var unionTypes: Map<UnionType> = {};
var stringLiteralTypes: Map<StringLiteralType> = {};
var emitExtends = false;
var mergedSymbols: Symbol[] = [];
var symbolLinks: SymbolLinks[] = [];
var nodeLinks: NodeLinks[] = [];
var potentialThisCollisions: Node[] = [];
var diagnostics: Diagnostic[] = [];
var diagnosticsModified: boolean = false;
function addDiagnostic(diagnostic: Diagnostic) {
diagnostics.push(diagnostic);
diagnosticsModified = true;
}
function error(location: Node, message: DiagnosticMessage, arg0?: any, arg1?: any, arg2?: any): void {
var diagnostic = location
? createDiagnosticForNode(location, message, arg0, arg1, arg2)
: createCompilerDiagnostic(message, arg0, arg1, arg2);
addDiagnostic(diagnostic);
}
function createSymbol(flags: SymbolFlags, name: string): Symbol {
return new Symbol(flags, name);
}
function getExcludedSymbolFlags(flags: SymbolFlags): SymbolFlags {
var result: SymbolFlags = 0;
if (flags & SymbolFlags.BlockScopedVariable) result |= SymbolFlags.BlockScopedVariableExcludes;
if (flags & SymbolFlags.FunctionScopedVariable) result |= SymbolFlags.FunctionScopedVariableExcludes;
if (flags & SymbolFlags.Property) result |= SymbolFlags.PropertyExcludes;
if (flags & SymbolFlags.EnumMember) result |= SymbolFlags.EnumMemberExcludes;
if (flags & SymbolFlags.Function) result |= SymbolFlags.FunctionExcludes;
if (flags & SymbolFlags.Class) result |= SymbolFlags.ClassExcludes;
if (flags & SymbolFlags.Interface) result |= SymbolFlags.InterfaceExcludes;
if (flags & SymbolFlags.RegularEnum) result |= SymbolFlags.RegularEnumExcludes;
if (flags & SymbolFlags.ConstEnum) result |= SymbolFlags.ConstEnumExcludes;
if (flags & SymbolFlags.ValueModule) result |= SymbolFlags.ValueModuleExcludes;
if (flags & SymbolFlags.Method) result |= SymbolFlags.MethodExcludes;
if (flags & SymbolFlags.GetAccessor) result |= SymbolFlags.GetAccessorExcludes;
if (flags & SymbolFlags.SetAccessor) result |= SymbolFlags.SetAccessorExcludes;
if (flags & SymbolFlags.TypeParameter) result |= SymbolFlags.TypeParameterExcludes;
if (flags & SymbolFlags.TypeAlias) result |= SymbolFlags.TypeAliasExcludes;
if (flags & SymbolFlags.Import) result |= SymbolFlags.ImportExcludes;
return result;
}
function recordMergedSymbol(target: Symbol, source: Symbol) {
if (!source.mergeId) source.mergeId = nextMergeId++;
mergedSymbols[source.mergeId] = target;
}
function cloneSymbol(symbol: Symbol): Symbol {
var result = createSymbol(symbol.flags | SymbolFlags.Merged, symbol.name);
result.declarations = symbol.declarations.slice(0);
result.parent = symbol.parent;
if (symbol.valueDeclaration) result.valueDeclaration = symbol.valueDeclaration;
if (symbol.constEnumOnlyModule) result.constEnumOnlyModule = true;
if (symbol.members) result.members = cloneSymbolTable(symbol.members);
if (symbol.exports) result.exports = cloneSymbolTable(symbol.exports);
recordMergedSymbol(result, symbol);
return result;
}
function extendSymbol(target: Symbol, source: Symbol) {
if (!(target.flags & getExcludedSymbolFlags(source.flags))) {
if (source.flags & SymbolFlags.ValueModule && target.flags & SymbolFlags.ValueModule && target.constEnumOnlyModule && !source.constEnumOnlyModule) {
// reset flag when merging instantiated module into value module that has only const enums
target.constEnumOnlyModule = false;
}
target.flags |= source.flags;
if (!target.valueDeclaration && source.valueDeclaration) target.valueDeclaration = source.valueDeclaration;
forEach(source.declarations, node => {
target.declarations.push(node);
});
if (source.members) {
if (!target.members) target.members = {};
extendSymbolTable(target.members, source.members);
}
if (source.exports) {
if (!target.exports) target.exports = {};
extendSymbolTable(target.exports, source.exports);
}
recordMergedSymbol(target, source);
}
else {
var message = target.flags & SymbolFlags.BlockScopedVariable || source.flags & SymbolFlags.BlockScopedVariable
? Diagnostics.Cannot_redeclare_block_scoped_variable_0 : Diagnostics.Duplicate_identifier_0;
forEach(source.declarations, node => {
error(node.name ? node.name : node, message, symbolToString(source));
});
forEach(target.declarations, node => {
error(node.name ? node.name : node, message, symbolToString(source));
});
}
}
function cloneSymbolTable(symbolTable: SymbolTable): SymbolTable {
var result: SymbolTable = {};
for (var id in symbolTable) {
if (hasProperty(symbolTable, id)) {
result[id] = symbolTable[id];
}
}
return result;
}
function extendSymbolTable(target: SymbolTable, source: SymbolTable) {
for (var id in source) {
if (hasProperty(source, id)) {
if (!hasProperty(target, id)) {
target[id] = source[id];
}
else {
var symbol = target[id];
if (!(symbol.flags & SymbolFlags.Merged)) {
target[id] = symbol = cloneSymbol(symbol);
}
extendSymbol(symbol, source[id]);
}
}
}
}
function getSymbolLinks(symbol: Symbol): SymbolLinks {
if (symbol.flags & SymbolFlags.Transient) return <TransientSymbol>symbol;
if (!symbol.id) symbol.id = nextSymbolId++;
return symbolLinks[symbol.id] || (symbolLinks[symbol.id] = {});
}
function getNodeLinks(node: Node): NodeLinks {
if (!node.id) node.id = nextNodeId++;
return nodeLinks[node.id] || (nodeLinks[node.id] = {});
}
function getSourceFile(node: Node): SourceFile {
return <SourceFile>getAncestor(node, SyntaxKind.SourceFile);
}
function isGlobalSourceFile(node: Node) {
return node.kind === SyntaxKind.SourceFile && !isExternalModule(<SourceFile>node);
}
function getSymbol(symbols: SymbolTable, name: string, meaning: SymbolFlags): Symbol {
if (meaning && hasProperty(symbols, name)) {
var symbol = symbols[name];
Debug.assert((symbol.flags & SymbolFlags.Instantiated) === 0, "Should never get an instantiated symbol here.");
if (symbol.flags & meaning) {
return symbol;
}
if (symbol.flags & SymbolFlags.Import) {
var target = resolveImport(symbol);
// unknown symbol will mean that there were reported error during import resolution
// treat it as positive answer to avoid cascading errors
if (target === unknownSymbol || target.flags & meaning) {
return symbol;
}
}
}
// return undefined if we can't find a symbol.
}
/** Returns true if node1 is defined before node 2**/
function isDefinedBefore(node1: Node, node2: Node): boolean {
var file1 = getSourceFileOfNode(node1);
var file2 = getSourceFileOfNode(node2);
if (file1 === file2) {
return node1.pos <= node2.pos;
}
if (!compilerOptions.out) {
return true;
}
var sourceFiles = program.getSourceFiles();
return sourceFiles.indexOf(file1) <= sourceFiles.indexOf(file2);
}
// Resolve a given name for a given meaning at a given location. An error is reported if the name was not found and
// the nameNotFoundMessage argument is not undefined. Returns the resolved symbol, or undefined if no symbol with
// the given name can be found.
function resolveName(location: Node, name: string, meaning: SymbolFlags, nameNotFoundMessage: DiagnosticMessage, nameArg: string | Identifier): Symbol {
var result: Symbol;
var lastLocation: Node;
var propertyWithInvalidInitializer: Node;
var errorLocation = location;
loop: while (location) {
// Locals of a source file are not in scope (because they get merged into the global symbol table)
if (location.locals && !isGlobalSourceFile(location)) {
if (result = getSymbol(location.locals, name, meaning)) {
break loop;
}
}
switch (location.kind) {
case SyntaxKind.SourceFile:
if (!isExternalModule(<SourceFile>location)) break;
case SyntaxKind.ModuleDeclaration:
if (result = getSymbol(getSymbolOfNode(location).exports, name, meaning & SymbolFlags.ModuleMember)) {
break loop;
}
break;
case SyntaxKind.EnumDeclaration:
if (result = getSymbol(getSymbolOfNode(location).exports, name, meaning & SymbolFlags.EnumMember)) {
break loop;
}
break;
case SyntaxKind.Property:
// TypeScript 1.0 spec (April 2014): 8.4.1
// Initializer expressions for instance member variables are evaluated in the scope
// of the class constructor body but are not permitted to reference parameters or
// local variables of the constructor. This effectively means that entities from outer scopes
// by the same name as a constructor parameter or local variable are inaccessible
// in initializer expressions for instance member variables.
if (location.parent.kind === SyntaxKind.ClassDeclaration && !(location.flags & NodeFlags.Static)) {
var ctor = findConstructorDeclaration(<ClassDeclaration>location.parent);
if (ctor && ctor.locals) {
if (getSymbol(ctor.locals, name, meaning & SymbolFlags.Value)) {
// Remember the property node, it will be used later to report appropriate error
propertyWithInvalidInitializer = location;
}
}
}
break;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
if (result = getSymbol(getSymbolOfNode(location).members, name, meaning & SymbolFlags.Type)) {
if (lastLocation && lastLocation.flags & NodeFlags.Static) {
// TypeScript 1.0 spec (April 2014): 3.4.1
// The scope of a type parameter extends over the entire declaration with which the type
// parameter list is associated, with the exception of static member declarations in classes.
error(errorLocation, Diagnostics.Static_members_cannot_reference_class_type_parameters);
return undefined;
}
break loop;
}
break;
case SyntaxKind.Method:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ArrowFunction:
if (name === "arguments") {
result = argumentsSymbol;
break loop;
}
break;
case SyntaxKind.FunctionExpression:
if (name === "arguments") {
result = argumentsSymbol;
break loop;
}
var id = (<FunctionExpression>location).name;
if (id && name === id.text) {
result = location.symbol;
break loop;
}
break;
case SyntaxKind.CatchBlock:
var id = (<CatchBlock>location).variable;
if (name === id.text) {
result = location.symbol;
break loop;
}
break;
}
lastLocation = location;
location = location.parent;
}
if (!result) {
result = getSymbol(globals, name, meaning);
}
if (!result) {
if (nameNotFoundMessage) {
error(errorLocation, nameNotFoundMessage, typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
}
return undefined;
}
// Perform extra checks only if error reporting was requested
if (nameNotFoundMessage) {
if (propertyWithInvalidInitializer) {
// We have a match, but the reference occurred within a property initializer and the identifier also binds
// to a local variable in the constructor where the code will be emitted.
var propertyName = (<PropertyDeclaration>propertyWithInvalidInitializer).name;
error(errorLocation, Diagnostics.Initializer_of_instance_member_variable_0_cannot_reference_identifier_1_declared_in_the_constructor,
declarationNameToString(propertyName), typeof nameArg === "string" ? nameArg : declarationNameToString(nameArg));
return undefined;
}
if (result.flags & SymbolFlags.BlockScopedVariable) {
// Block-scoped variables cannot be used before their definition
var declaration = forEach(result.declarations, d => d.flags & NodeFlags.BlockScoped ? d : undefined);
Debug.assert(declaration !== undefined, "Block-scoped variable declaration is undefined");
if (!isDefinedBefore(declaration, errorLocation)) {
error(errorLocation, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, declarationNameToString(declaration.name));
}
}
}
return result;
}
function resolveImport(symbol: Symbol): Symbol {
Debug.assert((symbol.flags & SymbolFlags.Import) !== 0, "Should only get Imports here.");
var links = getSymbolLinks(symbol);
if (!links.target) {
links.target = resolvingSymbol;
var node = <ImportDeclaration>getDeclarationOfKind(symbol, SyntaxKind.ImportDeclaration);
var target = node.moduleReference.kind === SyntaxKind.ExternalModuleReference
? resolveExternalModuleName(node, getExternalModuleImportDeclarationExpression(node))
: getSymbolOfPartOfRightHandSideOfImport(<EntityName>node.moduleReference, node);
if (links.target === resolvingSymbol) {
links.target = target || unknownSymbol;
}
else {
error(node, Diagnostics.Circular_definition_of_import_alias_0, symbolToString(symbol));
}
}
else if (links.target === resolvingSymbol) {
links.target = unknownSymbol;
}
return links.target;
}
// This function is only for imports with entity names
function getSymbolOfPartOfRightHandSideOfImport(entityName: EntityName, importDeclaration?: ImportDeclaration): Symbol {
if (!importDeclaration) {
importDeclaration = <ImportDeclaration>getAncestor(entityName, SyntaxKind.ImportDeclaration);
Debug.assert(importDeclaration !== undefined);
}
// There are three things we might try to look for. In the following examples,
// the search term is enclosed in |...|:
//
// import a = |b|; // Namespace
// import a = |b.c|; // Value, type, namespace
// import a = |b.c|.d; // Namespace
if (entityName.kind === SyntaxKind.Identifier && isRightSideOfQualifiedNameOrPropertyAccess(entityName)) {
entityName = <QualifiedName>entityName.parent;
}
// Check for case 1 and 3 in the above example
if (entityName.kind === SyntaxKind.Identifier || entityName.parent.kind === SyntaxKind.QualifiedName) {
return resolveEntityName(importDeclaration, entityName, SymbolFlags.Namespace);
}
else {
// Case 2 in above example
// entityName.kind could be a QualifiedName or a Missing identifier
Debug.assert(entityName.parent.kind === SyntaxKind.ImportDeclaration);
return resolveEntityName(importDeclaration, entityName, SymbolFlags.Value | SymbolFlags.Type | SymbolFlags.Namespace);
}
}
function getFullyQualifiedName(symbol: Symbol): string {
return symbol.parent ? getFullyQualifiedName(symbol.parent) + "." + symbolToString(symbol) : symbolToString(symbol);
}
// Resolves a qualified name and any involved import aliases
function resolveEntityName(location: Node, name: EntityName, meaning: SymbolFlags): Symbol {
if (getFullWidth(name) === 0) {
return undefined;
}
if (name.kind === SyntaxKind.Identifier) {
var symbol = resolveName(location,(<Identifier>name).text, meaning, Diagnostics.Cannot_find_name_0, <Identifier>name);
if (!symbol) {
return;
}
}
else if (name.kind === SyntaxKind.QualifiedName) {
var namespace = resolveEntityName(location,(<QualifiedName>name).left, SymbolFlags.Namespace);
if (!namespace || namespace === unknownSymbol || getFullWidth((<QualifiedName>name).right) === 0) return;
var symbol = getSymbol(namespace.exports,(<QualifiedName>name).right.text, meaning);
if (!symbol) {
error(location, Diagnostics.Module_0_has_no_exported_member_1, getFullyQualifiedName(namespace),
declarationNameToString((<QualifiedName>name).right));
return;
}
}
Debug.assert((symbol.flags & SymbolFlags.Instantiated) === 0, "Should never get an instantiated symbol here.");
return symbol.flags & meaning ? symbol : resolveImport(symbol);
}
function isExternalModuleNameRelative(moduleName: string): boolean {
// TypeScript 1.0 spec (April 2014): 11.2.1
// An external module name is "relative" if the first term is "." or "..".
return moduleName.substr(0, 2) === "./" || moduleName.substr(0, 3) === "../" || moduleName.substr(0, 2) === ".\\" || moduleName.substr(0, 3) === "..\\";
}
function resolveExternalModuleName(location: Node, moduleExpression: Expression): Symbol {
if (moduleExpression.kind !== SyntaxKind.StringLiteral) {
return;
}
var moduleLiteral = <LiteralExpression>moduleExpression;
var searchPath = getDirectoryPath(getSourceFile(location).filename);
var moduleName = moduleLiteral.text;
if (!moduleName) return;
var isRelative = isExternalModuleNameRelative(moduleName);
if (!isRelative) {
var symbol = getSymbol(globals, '"' + moduleName + '"', SymbolFlags.ValueModule);
if (symbol) {
return getResolvedExportSymbol(symbol);
}
}
while (true) {
var filename = normalizePath(combinePaths(searchPath, moduleName));
var sourceFile = program.getSourceFile(filename + ".ts") || program.getSourceFile(filename + ".d.ts");
if (sourceFile || isRelative) break;
var parentPath = getDirectoryPath(searchPath);
if (parentPath === searchPath) break;
searchPath = parentPath;
}
if (sourceFile) {
if (sourceFile.symbol) {
return getResolvedExportSymbol(sourceFile.symbol);
}
error(moduleLiteral, Diagnostics.File_0_is_not_an_external_module, sourceFile.filename);
return;
}
error(moduleLiteral, Diagnostics.Cannot_find_external_module_0, moduleName);
}
function getResolvedExportSymbol(moduleSymbol: Symbol): Symbol {
var symbol = getExportAssignmentSymbol(moduleSymbol);
if (symbol) {
if (symbol.flags & (SymbolFlags.Value | SymbolFlags.Type | SymbolFlags.Namespace)) {
return symbol;
}
if (symbol.flags & SymbolFlags.Import) {
return resolveImport(symbol);
}
}
return moduleSymbol;
}
function getExportAssignmentSymbol(symbol: Symbol): Symbol {
checkTypeOfExportAssignmentSymbol(symbol);
var symbolLinks = getSymbolLinks(symbol);
return symbolLinks.exportAssignSymbol === unknownSymbol ? undefined : symbolLinks.exportAssignSymbol;
}
function checkTypeOfExportAssignmentSymbol(containerSymbol: Symbol): void {
var symbolLinks = getSymbolLinks(containerSymbol);
if (!symbolLinks.exportAssignSymbol) {
var exportInformation = collectExportInformationForSourceFileOrModule(containerSymbol);
if (exportInformation.exportAssignments.length) {
if (exportInformation.exportAssignments.length > 1) {
// TypeScript 1.0 spec (April 2014): 11.2.4
// It is an error for an external module to contain more than one export assignment.
forEach(exportInformation.exportAssignments, node => error(node, Diagnostics.A_module_cannot_have_more_than_one_export_assignment));
}
var node = exportInformation.exportAssignments[0];
if (exportInformation.hasExportedMember) {
// TypeScript 1.0 spec (April 2014): 11.2.3
// If an external module contains an export assignment it is an error
// for the external module to also contain export declarations.
// The two types of exports are mutually exclusive.
error(node, Diagnostics.An_export_assignment_cannot_be_used_in_a_module_with_other_exported_elements);
}
if (node.exportName.text) {
var meaning = SymbolFlags.Value | SymbolFlags.Type | SymbolFlags.Namespace;
var exportSymbol = resolveName(node, node.exportName.text, meaning, Diagnostics.Cannot_find_name_0, node.exportName);
}
}
symbolLinks.exportAssignSymbol = exportSymbol || unknownSymbol;
}
}
function collectExportInformationForSourceFileOrModule(symbol: Symbol) {
var seenExportedMember = false;
var result: ExportAssignment[] = [];
forEach(symbol.declarations, declaration => {
var block = <Block>(declaration.kind === SyntaxKind.SourceFile ? declaration : (<ModuleDeclaration>declaration).body);
forEach(block.statements, node => {
if (node.kind === SyntaxKind.ExportAssignment) {
result.push(<ExportAssignment>node);
}
else {
seenExportedMember = seenExportedMember || (node.flags & NodeFlags.Export) !== 0;
}
});
});
return {
hasExportedMember: seenExportedMember,
exportAssignments: result
};
}
function getMergedSymbol(symbol: Symbol): Symbol {
var merged: Symbol;
return symbol && symbol.mergeId && (merged = mergedSymbols[symbol.mergeId]) ? merged : symbol;
}
function getSymbolOfNode(node: Node): Symbol {
return getMergedSymbol(node.symbol);
}
function getParentOfSymbol(symbol: Symbol): Symbol {
return getMergedSymbol(symbol.parent);
}
function getExportSymbolOfValueSymbolIfExported(symbol: Symbol): Symbol {
return symbol && (symbol.flags & SymbolFlags.ExportValue) !== 0
? getMergedSymbol(symbol.exportSymbol)
: symbol;
}
function symbolIsValue(symbol: Symbol): boolean {
// If it is an instantiated symbol, then it is a value if the symbol it is an
// instantiation of is a value.
if (symbol.flags & SymbolFlags.Instantiated) {
return symbolIsValue(getSymbolLinks(symbol).target);
}
// If the symbol has the value flag, it is trivially a value.
if (symbol.flags & SymbolFlags.Value) {
return true;
}
// If it is an import, then it is a value if the symbol it resolves to is a value.
if (symbol.flags & SymbolFlags.Import) {
return (resolveImport(symbol).flags & SymbolFlags.Value) !== 0;
}
return false;
}
function findConstructorDeclaration(node: ClassDeclaration): ConstructorDeclaration {
var members = node.members;
for (var i = 0; i < members.length; i++) {
var member = members[i];
if (member.kind === SyntaxKind.Constructor && (<ConstructorDeclaration>member).body) {
return <ConstructorDeclaration>member;
}
}
}
function createType(flags: TypeFlags): Type {
var result = new Type(checker, flags);
result.id = typeCount++;
return result;
}
function createIntrinsicType(kind: TypeFlags, intrinsicName: string): IntrinsicType {
var type = <IntrinsicType>createType(kind);
type.intrinsicName = intrinsicName;
return type;
}
function createObjectType(kind: TypeFlags, symbol?: Symbol): ObjectType {
var type = <ObjectType>createType(kind);
type.symbol = symbol;
return type;
}
// A reserved member name starts with two underscores followed by a non-underscore
function isReservedMemberName(name: string) {
return name.charCodeAt(0) === CharacterCodes._ && name.charCodeAt(1) === CharacterCodes._ && name.charCodeAt(2) !== CharacterCodes._;
}
function getNamedMembers(members: SymbolTable): Symbol[] {
var result: Symbol[];
for (var id in members) {
if (hasProperty(members, id)) {
if (!isReservedMemberName(id)) {
if (!result) result = [];
var symbol = members[id];
if (symbolIsValue(symbol)) {
result.push(symbol);
}
}
}
}
return result || emptyArray;
}
function setObjectTypeMembers(type: ObjectType, members: SymbolTable, callSignatures: Signature[], constructSignatures: Signature[], stringIndexType: Type, numberIndexType: Type): ResolvedType {
(<ResolvedType>type).members = members;
(<ResolvedType>type).properties = getNamedMembers(members);
(<ResolvedType>type).callSignatures = callSignatures;
(<ResolvedType>type).constructSignatures = constructSignatures;
if (stringIndexType) (<ResolvedType>type).stringIndexType = stringIndexType;
if (numberIndexType) (<ResolvedType>type).numberIndexType = numberIndexType;
return <ResolvedType>type;
}
function createAnonymousType(symbol: Symbol, members: SymbolTable, callSignatures: Signature[], constructSignatures: Signature[], stringIndexType: Type, numberIndexType: Type): ResolvedType {
return setObjectTypeMembers(createObjectType(TypeFlags.Anonymous, symbol),
members, callSignatures, constructSignatures, stringIndexType, numberIndexType);
}
function isOptionalProperty(propertySymbol: Symbol): boolean {
// class C {
// constructor(public x?) { }
// }
//
// x is an optional parameter, but it is a required property.
return propertySymbol.valueDeclaration &&
hasQuestionToken(propertySymbol.valueDeclaration) &&
propertySymbol.valueDeclaration.kind !== SyntaxKind.Parameter;
}
function forEachSymbolTableInScope<T>(enclosingDeclaration: Node, callback: (symbolTable: SymbolTable) => T): T {
var result: T;
for (var location = enclosingDeclaration; location; location = location.parent) {
// Locals of a source file are not in scope (because they get merged into the global symbol table)
if (location.locals && !isGlobalSourceFile(location)) {
if (result = callback(location.locals)) {
return result;
}
}
switch (location.kind) {
case SyntaxKind.SourceFile:
if (!isExternalModule(<SourceFile>location)) {
break;
}
case SyntaxKind.ModuleDeclaration:
if (result = callback(getSymbolOfNode(location).exports)) {
return result;
}
break;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
if (result = callback(getSymbolOfNode(location).members)) {
return result;
}
break;
}
}
return callback(globals);
}
function getQualifiedLeftMeaning(rightMeaning: SymbolFlags) {
// If we are looking in value space, the parent meaning is value, other wise it is namespace
return rightMeaning === SymbolFlags.Value ? SymbolFlags.Value : SymbolFlags.Namespace;
}
function getAccessibleSymbolChain(symbol: Symbol, enclosingDeclaration: Node, meaning: SymbolFlags, useOnlyExternalAliasing: boolean): Symbol[] {
function getAccessibleSymbolChainFromSymbolTable(symbols: SymbolTable): Symbol[] {
function canQualifySymbol(symbolFromSymbolTable: Symbol, meaning: SymbolFlags) {
// If the symbol is equivalent and doesn't need further qualification, this symbol is accessible
if (!needsQualification(symbolFromSymbolTable, enclosingDeclaration, meaning)) {
return true;
}
// If symbol needs qualification, make sure that parent is accessible, if it is then this symbol is accessible too
var accessibleParent = getAccessibleSymbolChain(symbolFromSymbolTable.parent, enclosingDeclaration, getQualifiedLeftMeaning(meaning), useOnlyExternalAliasing);
return !!accessibleParent;
}
function isAccessible(symbolFromSymbolTable: Symbol, resolvedAliasSymbol?: Symbol) {
if (symbol === (resolvedAliasSymbol || symbolFromSymbolTable)) {
// if the symbolFromSymbolTable is not external module (it could be if it was determined as ambient external module and would be in globals table)
// and if symbolfrom symbolTable or alias resolution matches the symbol,
// check the symbol can be qualified, it is only then this symbol is accessible
return !forEach(symbolFromSymbolTable.declarations, declaration => hasExternalModuleSymbol(declaration)) &&
canQualifySymbol(symbolFromSymbolTable, meaning);
}
}
// If symbol is directly available by its name in the symbol table
if (isAccessible(lookUp(symbols, symbol.name))) {
return [symbol];
}
// Check if symbol is any of the alias
return forEachValue(symbols, symbolFromSymbolTable => {
if (symbolFromSymbolTable.flags & SymbolFlags.Import) {
if (!useOnlyExternalAliasing || // We can use any type of alias to get the name
// Is this external alias, then use it to name
ts.forEach(symbolFromSymbolTable.declarations, isExternalModuleImportDeclaration)) {
var resolvedImportedSymbol = resolveImport(symbolFromSymbolTable);
if (isAccessible(symbolFromSymbolTable, resolveImport(symbolFromSymbolTable))) {
return [symbolFromSymbolTable];
}
// Look in the exported members, if we can find accessibleSymbolChain, symbol is accessible using this chain
// but only if the symbolFromSymbolTable can be qualified
var accessibleSymbolsFromExports = resolvedImportedSymbol.exports ? getAccessibleSymbolChainFromSymbolTable(resolvedImportedSymbol.exports) : undefined;
if (accessibleSymbolsFromExports && canQualifySymbol(symbolFromSymbolTable, getQualifiedLeftMeaning(meaning))) {
return [symbolFromSymbolTable].concat(accessibleSymbolsFromExports);
}
}
}
});
}
if (symbol) {
return forEachSymbolTableInScope(enclosingDeclaration, getAccessibleSymbolChainFromSymbolTable);
}
}
function needsQualification(symbol: Symbol, enclosingDeclaration: Node, meaning: SymbolFlags) {
var qualify = false;
forEachSymbolTableInScope(enclosingDeclaration, symbolTable => {
// If symbol of this name is not available in the symbol table we are ok
if (!hasProperty(symbolTable, symbol.name)) {
// Continue to the next symbol table
return false;
}
// If the symbol with this name is present it should refer to the symbol
var symbolFromSymbolTable = symbolTable[symbol.name];
if (symbolFromSymbolTable === symbol) {
// No need to qualify
return true;
}
// Qualify if the symbol from symbol table has same meaning as expected
symbolFromSymbolTable = (symbolFromSymbolTable.flags & SymbolFlags.Import) ? resolveImport(symbolFromSymbolTable) : symbolFromSymbolTable;
if (symbolFromSymbolTable.flags & meaning) {
qualify = true;
return true;
}
// Continue to the next symbol table
return false;
});
return qualify;
}
function isSymbolAccessible(symbol: Symbol, enclosingDeclaration: Node, meaning: SymbolFlags): SymbolAccessiblityResult {
if (symbol && enclosingDeclaration && !(symbol.flags & SymbolFlags.TypeParameter)) {
var initialSymbol = symbol;
var meaningToLook = meaning;
while (symbol) {
// Symbol is accessible if it by itself is accessible
var accessibleSymbolChain = getAccessibleSymbolChain(symbol, enclosingDeclaration, meaningToLook, /*useOnlyExternalAliasing*/ false);
if (accessibleSymbolChain) {
var hasAccessibleDeclarations = hasVisibleDeclarations(accessibleSymbolChain[0]);
if (!hasAccessibleDeclarations) {
return <SymbolAccessiblityResult>{
accessibility: SymbolAccessibility.NotAccessible,
errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
errorModuleName: symbol !== initialSymbol ? symbolToString(symbol, enclosingDeclaration, SymbolFlags.Namespace) : undefined,
};
}
return hasAccessibleDeclarations;
}
// If we haven't got the accessible symbol, it doesn't mean the symbol is actually inaccessible.
// It could be a qualified symbol and hence verify the path
// e.g.:
// module m {
// export class c {
// }
// }
// var x: typeof m.c
// In the above example when we start with checking if typeof m.c symbol is accessible,
// we are going to see if c can be accessed in scope directly.
// But it can't, hence the accessible is going to be undefined, but that doesn't mean m.c is inaccessible
// It is accessible if the parent m is accessible because then m.c can be accessed through qualification
meaningToLook = getQualifiedLeftMeaning(meaning);
symbol = getParentOfSymbol(symbol);
}
// This could be a symbol that is not exported in the external module
// or it could be a symbol from different external module that is not aliased and hence cannot be named
var symbolExternalModule = forEach(initialSymbol.declarations, declaration => getExternalModuleContainer(declaration));
if (symbolExternalModule) {
var enclosingExternalModule = getExternalModuleContainer(enclosingDeclaration);
if (symbolExternalModule !== enclosingExternalModule) {
// name from different external module that is not visible
return {
accessibility: SymbolAccessibility.CannotBeNamed,
errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
errorModuleName: symbolToString(symbolExternalModule)
};
}
}
// Just a local name that is not accessible
return {
accessibility: SymbolAccessibility.NotAccessible,
errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
};
}
return { accessibility: SymbolAccessibility.Accessible };
function getExternalModuleContainer(declaration: Node) {
for (; declaration; declaration = declaration.parent) {
if (hasExternalModuleSymbol(declaration)) {
return getSymbolOfNode(declaration);
}
}
}
}
function hasExternalModuleSymbol(declaration: Node) {
return (declaration.kind === SyntaxKind.ModuleDeclaration && (<ModuleDeclaration>declaration).name.kind === SyntaxKind.StringLiteral) ||
(declaration.kind === SyntaxKind.SourceFile && isExternalModule(<SourceFile>declaration));
}
function hasVisibleDeclarations(symbol: Symbol): SymbolVisibilityResult {
var aliasesToMakeVisible: ImportDeclaration[];
if (forEach(symbol.declarations, declaration => !getIsDeclarationVisible(declaration))) {
return undefined;
}
return { accessibility: SymbolAccessibility.Accessible, aliasesToMakeVisible };
function getIsDeclarationVisible(declaration: Declaration) {
if (!isDeclarationVisible(declaration)) {
// Mark the unexported alias as visible if its parent is visible
// because these kind of aliases can be used to name types in declaration file
if (declaration.kind === SyntaxKind.ImportDeclaration &&
!(declaration.flags & NodeFlags.Export) &&
isDeclarationVisible(<Declaration>declaration.parent)) {
getNodeLinks(declaration).isVisible = true;
if (aliasesToMakeVisible) {
if (!contains(aliasesToMakeVisible, declaration)) {
aliasesToMakeVisible.push(<ImportDeclaration>declaration);
}
}
else {
aliasesToMakeVisible = [<ImportDeclaration>declaration];
}
return true;
}
// Declaration is not visible
return false;
}
return true;
}
}
function isEntityNameVisible(entityName: EntityName, enclosingDeclaration: Node): SymbolVisibilityResult {
// get symbol of the first identifier of the entityName
var meaning: SymbolFlags;
if (entityName.parent.kind === SyntaxKind.TypeQuery) {
// Typeof value
meaning = SymbolFlags.Value | SymbolFlags.ExportValue;
}
else if (entityName.kind === SyntaxKind.QualifiedName ||
entityName.parent.kind === SyntaxKind.ImportDeclaration) {
// Left identifier from type reference or TypeAlias
// Entity name of the import declaration
meaning = SymbolFlags.Namespace;
}
else {
// Type Reference or TypeAlias entity = Identifier
meaning = SymbolFlags.Type;
}
var firstIdentifier = getFirstIdentifier(entityName);
var symbol = resolveName(enclosingDeclaration, (<Identifier>firstIdentifier).text, meaning, /*nodeNotFoundErrorMessage*/ undefined, /*nameArg*/ undefined);
// Verify if the symbol is accessible
return hasVisibleDeclarations(symbol) || <SymbolVisibilityResult>{
accessibility: SymbolAccessibility.NotAccessible,
errorSymbolName: getTextOfNode(firstIdentifier),
errorNode: firstIdentifier
};
}
function releaseStringWriter(writer: StringSymbolWriter) {
writer.clear()
stringWriters.push(writer);
}
function writeKeyword(writer: SymbolWriter, kind: SyntaxKind) {
writer.writeKeyword(tokenToString(kind));
}
function writePunctuation(writer: SymbolWriter, kind: SyntaxKind) {
writer.writePunctuation(tokenToString(kind));
}
function writeOperator(writer: SymbolWriter, kind: SyntaxKind) {
writer.writeOperator(tokenToString(kind));
}
function writeSpace(writer: SymbolWriter) {
writer.writeSpace(" ");
}
function symbolToString(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags): string {
var writer = getSingleLineStringWriter();
getSymbolDisplayBuilder().buildSymbolDisplay(symbol, writer, enclosingDeclaration, meaning);
var result = writer.string();
releaseStringWriter(writer);
return result;
}
function typeToString(type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags): string {
var writer = getSingleLineStringWriter();
getSymbolDisplayBuilder().buildTypeDisplay(type, writer, enclosingDeclaration, flags);
var result = writer.string();
releaseStringWriter(writer);
var maxLength = compilerOptions.noErrorTruncation || flags & TypeFormatFlags.NoTruncation ? undefined : 100;
if (maxLength && result.length >= maxLength) {
result = result.substr(0, maxLength - "...".length) + "...";
}
return result;
}
function getTypeAliasForTypeLiteral(type: Type): Symbol {
if (type.symbol && type.symbol.flags & SymbolFlags.TypeLiteral) {
var node = type.symbol.declarations[0].parent;
while (node.kind === SyntaxKind.ParenthesizedType) {
node = node.parent;
}
if (node.kind === SyntaxKind.TypeAliasDeclaration) {
return getSymbolOfNode(node);
}
}
return undefined;
}
// This is for caching the result of getSymbolDisplayBuilder. Do not access directly.
var _displayBuilder: SymbolDisplayBuilder;
function getSymbolDisplayBuilder(): SymbolDisplayBuilder {
/**
* Writes only the name of the symbol out to the writer. Uses the original source text
* for the name of the symbol if it is available to match how the user inputted the name.
*/
function appendSymbolNameOnly(symbol: Symbol, writer: SymbolWriter): void {
if (symbol.declarations && symbol.declarations.length > 0) {
var declaration = symbol.declarations[0];
if (declaration.name) {
writer.writeSymbol(declarationNameToString(declaration.name), symbol);
return;
}
}
writer.writeSymbol(symbol.name, symbol);
}
/**
* Enclosing declaration is optional when we don't want to get qualified name in the enclosing declaration scope
* Meaning needs to be specified if the enclosing declaration is given
*/
function buildSymbolDisplay(symbol: Symbol, writer: SymbolWriter, enclosingDeclaration?: Node, meaning?: SymbolFlags, flags?: SymbolFormatFlags): void {
var parentSymbol: Symbol;
function appendParentTypeArgumentsAndSymbolName(symbol: Symbol): void {
if (parentSymbol) {
// Write type arguments of instantiated class/interface here
if (flags & SymbolFormatFlags.WriteTypeParametersOrArguments) {
if (symbol.flags & SymbolFlags.Instantiated) {
buildDisplayForTypeArgumentsAndDelimiters(getTypeParametersOfClassOrInterface(parentSymbol),
(<TransientSymbol>symbol).mapper, writer, enclosingDeclaration);
}
else {
buildTypeParameterDisplayFromSymbol(parentSymbol, writer, enclosingDeclaration);
}
}
writePunctuation(writer, SyntaxKind.DotToken);
}
parentSymbol = symbol;
appendSymbolNameOnly(symbol, writer);
}
// Let the writer know we just wrote out a symbol. The declaration emitter writer uses
// this to determine if an import it has previously seen (and not written out) needs
// to be written to the file once the walk of the tree is complete.
//
// NOTE(cyrusn): This approach feels somewhat unfortunate. A simple pass over the tree
// up front (for example, during checking) could determine if we need to emit the imports
// and we could then access that data during declaration emit.
writer.trackSymbol(symbol, enclosingDeclaration, meaning);
function walkSymbol(symbol: Symbol, meaning: SymbolFlags): void {
if (symbol) {
var accessibleSymbolChain = getAccessibleSymbolChain(symbol, enclosingDeclaration, meaning, !!(flags & SymbolFormatFlags.UseOnlyExternalAliasing));
if (!accessibleSymbolChain ||
needsQualification(accessibleSymbolChain[0], enclosingDeclaration, accessibleSymbolChain.length === 1 ? meaning : getQualifiedLeftMeaning(meaning))) {
// Go up and add our parent.
walkSymbol(
getParentOfSymbol(accessibleSymbolChain ? accessibleSymbolChain[0] : symbol),
getQualifiedLeftMeaning(meaning));
}
if (accessibleSymbolChain) {
for (var i = 0, n = accessibleSymbolChain.length; i < n; i++) {
appendParentTypeArgumentsAndSymbolName(accessibleSymbolChain[i]);
}
}
else {
// If we didn't find accessible symbol chain for this symbol, break if this is external module
if (!parentSymbol && ts.forEach(symbol.declarations, declaration => hasExternalModuleSymbol(declaration))) {
return;
}
// if this is anonymous type break
if (symbol.flags & SymbolFlags.TypeLiteral || symbol.flags & SymbolFlags.ObjectLiteral) {
return;
}
appendParentTypeArgumentsAndSymbolName(symbol);
}
}
}
// Get qualified name
if (enclosingDeclaration &&
// TypeParameters do not need qualification
!(symbol.flags & SymbolFlags.TypeParameter)) {
walkSymbol(symbol, meaning);
return;
}
return appendParentTypeArgumentsAndSymbolName(symbol);
}
function buildTypeDisplay(type: Type, writer: SymbolWriter, enclosingDeclaration?: Node, globalFlags?: TypeFormatFlags, typeStack?: Type[]) {
var globalFlagsToPass = globalFlags & TypeFormatFlags.WriteOwnNameForAnyLike;
return writeType(type, globalFlags);
function writeType(type: Type, flags: TypeFormatFlags) {
// Write undefined/null type as any
if (type.flags & TypeFlags.Intrinsic) {
// Special handling for unknown / resolving types, they should show up as any and not unknown or __resolving
writer.writeKeyword(!(globalFlags & TypeFormatFlags.WriteOwnNameForAnyLike) &&
(type.flags & TypeFlags.Any) ? "any" : (<IntrinsicType>type).intrinsicName);
}
else if (type.flags & TypeFlags.Reference) {
writeTypeReference(<TypeReference>type, flags);
}
else if (type.flags & (TypeFlags.Class | TypeFlags.Interface | TypeFlags.Enum | TypeFlags.TypeParameter)) {
buildSymbolDisplay(type.symbol, writer, enclosingDeclaration, SymbolFlags.Type);
}
else if (type.flags & TypeFlags.Tuple) {
writeTupleType(<TupleType>type);
}
else if (type.flags & TypeFlags.Union) {
writeUnionType(<UnionType>type, flags);
}
else if (type.flags & TypeFlags.Anonymous) {
writeAnonymousType(<ObjectType>type, flags);
}
else if (type.flags & TypeFlags.StringLiteral) {
writer.writeStringLiteral((<StringLiteralType>type).text);
}
else {
// Should never get here
// { ... }
writePunctuation(writer, SyntaxKind.OpenBraceToken);
writeSpace(writer);
writePunctuation(writer, SyntaxKind.DotDotDotToken);
writeSpace(writer);
writePunctuation(writer, SyntaxKind.CloseBraceToken);
}
}
function writeTypeList(types: Type[], union: boolean) {
for (var i = 0; i < types.length; i++) {
if (i > 0) {
if (union) {
writeSpace(writer);
}
writePunctuation(writer, union ? SyntaxKind.BarToken : SyntaxKind.CommaToken);
writeSpace(writer);
}
writeType(types[i], union ? TypeFormatFlags.InElementType : TypeFormatFlags.None);
}
}
function writeTypeReference(type: TypeReference, flags: TypeFormatFlags) {
if (type.target === globalArrayType && !(flags & TypeFormatFlags.WriteArrayAsGenericType)) {
writeType(type.typeArguments[0], TypeFormatFlags.InElementType);
writePunctuation(writer, SyntaxKind.OpenBracketToken);
writePunctuation(writer, SyntaxKind.CloseBracketToken);
}
else {
buildSymbolDisplay(type.target.symbol, writer, enclosingDeclaration, SymbolFlags.Type);
writePunctuation(writer, SyntaxKind.LessThanToken);
writeTypeList(type.typeArguments, /*union*/ false);
writePunctuation(writer, SyntaxKind.GreaterThanToken);
}
}
function writeTupleType(type: TupleType) {
writePunctuation(writer, SyntaxKind.OpenBracketToken);
writeTypeList(type.elementTypes, /*union*/ false);
writePunctuation(writer, SyntaxKind.CloseBracketToken);
}
function writeUnionType(type: UnionType, flags: TypeFormatFlags) {
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.OpenParenToken);
}
writeTypeList(type.types, /*union*/ true);
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.CloseParenToken);
}
}
function writeAnonymousType(type: ObjectType, flags: TypeFormatFlags) {
// Always use 'typeof T' for type of class, enum, and module objects
if (type.symbol && type.symbol.flags & (SymbolFlags.Class | SymbolFlags.Enum | SymbolFlags.ValueModule)) {
writeTypeofSymbol(type);
}
// Use 'typeof T' for types of functions and methods that circularly reference themselves
else if (shouldWriteTypeOfFunctionSymbol()) {
writeTypeofSymbol(type);
}
else if (typeStack && contains(typeStack, type)) {
// If type is an anonymous type literal in a type alias declaration, use type alias name
var typeAlias = getTypeAliasForTypeLiteral(type);
if (typeAlias) {
buildSymbolDisplay(typeAlias, writer, enclosingDeclaration, SymbolFlags.Type);
}
else {
// Recursive usage, use any
writeKeyword(writer, SyntaxKind.AnyKeyword);
}
}
else {
if (!typeStack) {
typeStack = [];
}
typeStack.push(type);
writeLiteralType(type, flags);
typeStack.pop();
}
function shouldWriteTypeOfFunctionSymbol() {
if (type.symbol) {
var isStaticMethodSymbol = !!(type.symbol.flags & SymbolFlags.Method && // typeof static method
ts.forEach(type.symbol.declarations, declaration => declaration.flags & NodeFlags.Static));
var isNonLocalFunctionSymbol = !!(type.symbol.flags & SymbolFlags.Function) &&
(type.symbol.parent || // is exported function symbol
ts.forEach(type.symbol.declarations, declaration =>
declaration.parent.kind === SyntaxKind.SourceFile || declaration.parent.kind === SyntaxKind.ModuleBlock));
if (isStaticMethodSymbol || isNonLocalFunctionSymbol) {
// typeof is allowed only for static/non local functions
return !!(flags & TypeFormatFlags.UseTypeOfFunction) || // use typeof if format flags specify it
(typeStack && contains(typeStack, type)); // it is type of the symbol uses itself recursively
}
}
}
}
function writeTypeofSymbol(type: ObjectType) {
writeKeyword(writer, SyntaxKind.TypeOfKeyword);
writeSpace(writer);
buildSymbolDisplay(type.symbol, writer, enclosingDeclaration, SymbolFlags.Value);
}
function writeLiteralType(type: ObjectType, flags: TypeFormatFlags) {
var resolved = resolveObjectOrUnionTypeMembers(type);
if (!resolved.properties.length && !resolved.stringIndexType && !resolved.numberIndexType) {
if (!resolved.callSignatures.length && !resolved.constructSignatures.length) {
writePunctuation(writer, SyntaxKind.OpenBraceToken);
writePunctuation(writer, SyntaxKind.CloseBraceToken);
return;
}
if (resolved.callSignatures.length === 1 && !resolved.constructSignatures.length) {
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.OpenParenToken);
}
buildSignatureDisplay(resolved.callSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature , typeStack);
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.CloseParenToken);
}
return;
}
if (resolved.constructSignatures.length === 1 && !resolved.callSignatures.length) {
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.OpenParenToken);
}
writeKeyword(writer, SyntaxKind.NewKeyword);
writeSpace(writer);
buildSignatureDisplay(resolved.constructSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature, typeStack);
if (flags & TypeFormatFlags.InElementType) {
writePunctuation(writer, SyntaxKind.CloseParenToken);
}
return;
}
}
writePunctuation(writer, SyntaxKind.OpenBraceToken);
writer.writeLine();
writer.increaseIndent();
for (var i = 0; i < resolved.callSignatures.length; i++) {
buildSignatureDisplay(resolved.callSignatures[i], writer, enclosingDeclaration, globalFlagsToPass, typeStack);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
for (var i = 0; i < resolved.constructSignatures.length; i++) {
writeKeyword(writer, SyntaxKind.NewKeyword);
writeSpace(writer);
buildSignatureDisplay(resolved.constructSignatures[i], writer, enclosingDeclaration, globalFlagsToPass, typeStack);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
if (resolved.stringIndexType) {
// [x: string]:
writePunctuation(writer, SyntaxKind.OpenBracketToken);
writer.writeParameter("x");
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
writeKeyword(writer, SyntaxKind.StringKeyword);
writePunctuation(writer, SyntaxKind.CloseBracketToken);
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
writeType(resolved.stringIndexType, TypeFormatFlags.None);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
if (resolved.numberIndexType) {
// [x: number]:
writePunctuation(writer, SyntaxKind.OpenBracketToken);
writer.writeParameter("x");
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
writeKeyword(writer, SyntaxKind.NumberKeyword);
writePunctuation(writer, SyntaxKind.CloseBracketToken);
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
writeType(resolved.numberIndexType, TypeFormatFlags.None);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
for (var i = 0; i < resolved.properties.length; i++) {
var p = resolved.properties[i];
var t = getTypeOfSymbol(p);
if (p.flags & (SymbolFlags.Function | SymbolFlags.Method) && !getPropertiesOfObjectType(t).length) {
var signatures = getSignaturesOfType(t, SignatureKind.Call);
for (var j = 0; j < signatures.length; j++) {
buildSymbolDisplay(p, writer);
if (isOptionalProperty(p)) {
writePunctuation(writer, SyntaxKind.QuestionToken);
}
buildSignatureDisplay(signatures[j], writer, enclosingDeclaration, globalFlagsToPass, typeStack);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
}
else {
buildSymbolDisplay(p, writer);
if (isOptionalProperty(p)) {
writePunctuation(writer, SyntaxKind.QuestionToken);
}
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
writeType(t, TypeFormatFlags.None);
writePunctuation(writer, SyntaxKind.SemicolonToken);
writer.writeLine();
}
}
writer.decreaseIndent();
writePunctuation(writer, SyntaxKind.CloseBraceToken);
}
}
function buildTypeParameterDisplayFromSymbol(symbol: Symbol, writer: SymbolWriter, enclosingDeclaraiton?: Node, flags?: TypeFormatFlags) {
var targetSymbol = getTargetSymbol(symbol);
if (targetSymbol.flags & SymbolFlags.Class || targetSymbol.flags & SymbolFlags.Interface) {
buildDisplayForTypeParametersAndDelimiters(getTypeParametersOfClassOrInterface(symbol), writer, enclosingDeclaraiton, flags);
}
}
function buildTypeParameterDisplay(tp: TypeParameter, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
appendSymbolNameOnly(tp.symbol, writer);
var constraint = getConstraintOfTypeParameter(tp);
if (constraint) {
writeSpace(writer);
writeKeyword(writer, SyntaxKind.ExtendsKeyword);
writeSpace(writer);
buildTypeDisplay(constraint, writer, enclosingDeclaration, flags, typeStack);
}
}
function buildParameterDisplay(p: Symbol, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
if (hasDotDotDotToken(p.valueDeclaration)) {
writePunctuation(writer, SyntaxKind.DotDotDotToken);
}
appendSymbolNameOnly(p, writer);
if (hasQuestionToken(p.valueDeclaration) || (<VariableDeclaration>p.valueDeclaration).initializer) {
writePunctuation(writer, SyntaxKind.QuestionToken);
}
writePunctuation(writer, SyntaxKind.ColonToken);
writeSpace(writer);
buildTypeDisplay(getTypeOfSymbol(p), writer, enclosingDeclaration, flags, typeStack);
}
function buildDisplayForTypeParametersAndDelimiters(typeParameters: TypeParameter[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
if (typeParameters && typeParameters.length) {
writePunctuation(writer, SyntaxKind.LessThanToken);
for (var i = 0; i < typeParameters.length; i++) {
if (i > 0) {
writePunctuation(writer, SyntaxKind.CommaToken);
writeSpace(writer);
}
buildTypeParameterDisplay(typeParameters[i], writer, enclosingDeclaration, flags, typeStack);
}
writePunctuation(writer, SyntaxKind.GreaterThanToken);
}
}
function buildDisplayForTypeArgumentsAndDelimiters(typeParameters: TypeParameter[], mapper: TypeMapper, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
if (typeParameters && typeParameters.length) {
writePunctuation(writer, SyntaxKind.LessThanToken);
for (var i = 0; i < typeParameters.length; i++) {
if (i > 0) {
writePunctuation(writer, SyntaxKind.CommaToken);
writeSpace(writer);
}
buildTypeDisplay(mapper(typeParameters[i]), writer, enclosingDeclaration, TypeFormatFlags.None);
}
writePunctuation(writer, SyntaxKind.GreaterThanToken);
}
}
function buildDisplayForParametersAndDelimiters(parameters: Symbol[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
writePunctuation(writer, SyntaxKind.OpenParenToken);
for (var i = 0; i < parameters.length; i++) {
if (i > 0) {
writePunctuation(writer, SyntaxKind.CommaToken);
writeSpace(writer);
}
buildParameterDisplay(parameters[i], writer, enclosingDeclaration, flags, typeStack);
}
writePunctuation(writer, SyntaxKind.CloseParenToken);
}
function buildReturnTypeDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
if (flags & TypeFormatFlags.WriteArrowStyleSignature) {
writeSpace(writer);
writePunctuation(writer, SyntaxKind.EqualsGreaterThanToken);
}
else {
writePunctuation(writer, SyntaxKind.ColonToken);
}
writeSpace(writer);
buildTypeDisplay(getReturnTypeOfSignature(signature), writer, enclosingDeclaration, flags, typeStack);
}
function buildSignatureDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) {
if (signature.target && (flags & TypeFormatFlags.WriteTypeArgumentsOfSignature)) {
// Instantiated signature, write type arguments instead
// This is achieved by passing in the mapper separately
buildDisplayForTypeArgumentsAndDelimiters(signature.target.typeParameters, signature.mapper, writer, enclosingDeclaration);
}
else {
buildDisplayForTypeParametersAndDelimiters(signature.typeParameters, writer, enclosingDeclaration, flags, typeStack);
}
buildDisplayForParametersAndDelimiters(signature.parameters, writer, enclosingDeclaration, flags, typeStack);
buildReturnTypeDisplay(signature, writer, enclosingDeclaration, flags, typeStack);
}
return _displayBuilder || (_displayBuilder = {
symbolToString: symbolToString,
typeToString: typeToString,
buildSymbolDisplay: buildSymbolDisplay,
buildTypeDisplay: buildTypeDisplay,
buildTypeParameterDisplay: buildTypeParameterDisplay,
buildParameterDisplay: buildParameterDisplay,
buildDisplayForParametersAndDelimiters: buildDisplayForParametersAndDelimiters,
buildDisplayForTypeParametersAndDelimiters: buildDisplayForTypeParametersAndDelimiters,
buildDisplayForTypeArgumentsAndDelimiters: buildDisplayForTypeArgumentsAndDelimiters,
buildTypeParameterDisplayFromSymbol: buildTypeParameterDisplayFromSymbol,
buildSignatureDisplay: buildSignatureDisplay,
buildReturnTypeDisplay: buildReturnTypeDisplay
});
}
function isDeclarationVisible(node: Declaration): boolean {
function getContainingExternalModule(node: Node) {
for (; node; node = node.parent) {
if (node.kind === SyntaxKind.ModuleDeclaration) {
if ((<ModuleDeclaration>node).name.kind === SyntaxKind.StringLiteral) {
return node;
}
}
else if (node.kind === SyntaxKind.SourceFile) {
return isExternalModule(<SourceFile>node) ? node : undefined;
}
}
Debug.fail("getContainingModule cant reach here");
}
function isUsedInExportAssignment(node: Node) {
// Get source File and see if it is external module and has export assigned symbol
var externalModule = getContainingExternalModule(node);
if (externalModule) {
// This is export assigned symbol node
var externalModuleSymbol = getSymbolOfNode(externalModule);
var exportAssignmentSymbol = getExportAssignmentSymbol(externalModuleSymbol);
var resolvedExportSymbol: Symbol;
var symbolOfNode = getSymbolOfNode(node);
if (isSymbolUsedInExportAssignment(symbolOfNode)) {
return true;
}
// if symbolOfNode is import declaration, resolve the symbol declaration and check
if (symbolOfNode.flags & SymbolFlags.Import) {
return isSymbolUsedInExportAssignment(resolveImport(symbolOfNode));
}
}
// Check if the symbol is used in export assignment
function isSymbolUsedInExportAssignment(symbol: Symbol) {
if (exportAssignmentSymbol === symbol) {
return true;
}
if (exportAssignmentSymbol && !!(exportAssignmentSymbol.flags & SymbolFlags.Import)) {
// if export assigned symbol is import declaration, resolve the import
resolvedExportSymbol = resolvedExportSymbol || resolveImport(exportAssignmentSymbol);
if (resolvedExportSymbol === symbol) {
return true;
}
// Container of resolvedExportSymbol is visible
return forEach(resolvedExportSymbol.declarations, (current: Node) => {
while (current) {
if (current === node) {
return true;
}
current = current.parent;
}
});
}
}
}
function determineIfDeclarationIsVisible() {
switch (node.kind) {
case SyntaxKind.VariableDeclaration:
case SyntaxKind.ModuleDeclaration:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.TypeAliasDeclaration:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.ImportDeclaration:
// In case of variable declaration, node.parent is variable statement so look at the variable statement's parent
var parent = node.kind === SyntaxKind.VariableDeclaration ? node.parent.parent : node.parent;
// If the node is not exported or it is not ambient module element (except import declaration)
if (!(node.flags & NodeFlags.Export) &&
!(node.kind !== SyntaxKind.ImportDeclaration && parent.kind !== SyntaxKind.SourceFile && isInAmbientContext(parent))) {
return isGlobalSourceFile(parent) || isUsedInExportAssignment(node);
}
// Exported members/ambient module elements (exception import declaration) are visible if parent is visible
return isDeclarationVisible(<Declaration>parent);
case SyntaxKind.Property:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.Method:
if (node.flags & (NodeFlags.Private | NodeFlags.Protected)) {
// Private/protected properties/methods are not visible
return false;
}
// Public properties/methods are visible if its parents are visible, so let it fall into next case statement
case SyntaxKind.Constructor:
case SyntaxKind.ConstructSignature:
case SyntaxKind.CallSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.Parameter:
case SyntaxKind.ModuleBlock:
case SyntaxKind.TypeParameter:
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.TypeLiteral:
case SyntaxKind.TypeReference:
case SyntaxKind.ArrayType:
case SyntaxKind.TupleType:
case SyntaxKind.UnionType:
case SyntaxKind.ParenthesizedType:
return isDeclarationVisible(<Declaration>node.parent);
// Source file is always visible
case SyntaxKind.SourceFile:
return true;
default:
Debug.fail("isDeclarationVisible unknown: SyntaxKind: " + node.kind);
}
}
if (node) {
var links = getNodeLinks(node);
if (links.isVisible === undefined) {
links.isVisible = !!determineIfDeclarationIsVisible();
}
return links.isVisible;
}
}
function getTypeOfPrototypeProperty(prototype: Symbol): Type {
// TypeScript 1.0 spec (April 2014): 8.4
// Every class automatically contains a static property member named 'prototype',
// the type of which is an instantiation of the class type with type Any supplied as a type argument for each type parameter.
// It is an error to explicitly declare a static property member with the name 'prototype'.
var classType = <InterfaceType>getDeclaredTypeOfSymbol(prototype.parent);
return classType.typeParameters ? createTypeReference(<GenericType>classType, map(classType.typeParameters, _ => anyType)) : classType;
}
function getTypeOfVariableOrParameterOrPropertyDeclaration(declaration: VariableOrParameterOrPropertyDeclaration): Type {
// A variable declared in a for..in statement is always of type any
if (declaration.parent.kind === SyntaxKind.ForInStatement) {
return anyType;
}
// Use type from type annotation if one is present
if (declaration.type) {
return getTypeFromTypeNode(declaration.type);
}
if (declaration.kind === SyntaxKind.Parameter) {
var func = <FunctionLikeDeclaration>declaration.parent;
// For a parameter of a set accessor, use the type of the get accessor if one is present
if (func.kind === SyntaxKind.SetAccessor && !hasComputedNameButNotSymbol(func)) {
var getter = <AccessorDeclaration>getDeclarationOfKind(declaration.parent.symbol, SyntaxKind.GetAccessor);
if (getter) {
return getReturnTypeOfSignature(getSignatureFromDeclaration(getter));
}
}
// Use contextual parameter type if one is available
var type = getContextuallyTypedParameterType(<ParameterDeclaration>declaration);
if (type) {
return type;
}
}
// Use the type of the initializer expression if one is present
if (declaration.initializer) {
var type = checkAndMarkExpression(declaration.initializer);
// Widening of property assignments is handled by checkObjectLiteral, exclude them here
if (declaration.kind !== SyntaxKind.PropertyAssignment) {
var unwidenedType = type;
type = getWidenedType(type);
if (type !== unwidenedType) {
checkImplicitAny(type);
}
}
return type;
}
// If it is a short-hand property assignment; Use the type of the identifier
if (declaration.kind === SyntaxKind.ShorthandPropertyAssignment) {
var type = checkIdentifier(<Identifier>declaration.name);
return type
}
// Rest parameters default to type any[], other parameters default to type any
var type = hasDotDotDotToken(declaration) ? createArrayType(anyType) : anyType;
checkImplicitAny(type);
return type;
function checkImplicitAny(type: Type) {
if (!fullTypeCheck || !compilerOptions.noImplicitAny) {
return;
}
// We need to have ended up with 'any', 'any[]', 'any[][]', etc.
if (getInnermostTypeOfNestedArrayTypes(type) !== anyType) {
return;
}
// Ignore privates within ambient contexts; they exist purely for documentative purposes to avoid name clashing.
// (e.g. privates within .d.ts files do not expose type information)
if (isPrivateWithinAmbient(declaration) || (declaration.kind === SyntaxKind.Parameter && isPrivateWithinAmbient(declaration.parent))) {
return;
}
switch (declaration.kind) {
case SyntaxKind.Property:
var diagnostic = Diagnostics.Member_0_implicitly_has_an_1_type;
break;
case SyntaxKind.Parameter:
var diagnostic = hasDotDotDotToken(declaration)
? Diagnostics.Rest_parameter_0_implicitly_has_an_any_type
: Diagnostics.Parameter_0_implicitly_has_an_1_type;
break;
default:
var diagnostic = Diagnostics.Variable_0_implicitly_has_an_1_type;
}
error(declaration, diagnostic, declarationNameToString(declaration.name), typeToString(type));
}
}
function getTypeOfVariableOrParameterOrProperty(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.type) {
// Handle prototype property
if (symbol.flags & SymbolFlags.Prototype) {
return links.type = getTypeOfPrototypeProperty(symbol);
}
// Handle catch clause variables
var declaration = symbol.valueDeclaration;
if (declaration.kind === SyntaxKind.CatchBlock) {
return links.type = anyType;
}
// Handle variable, parameter or property
links.type = resolvingType;
var type = getTypeOfVariableOrParameterOrPropertyDeclaration(<VariableDeclaration>declaration);
if (links.type === resolvingType) {
links.type = type;
}
}
else if (links.type === resolvingType) {
links.type = anyType;
if (compilerOptions.noImplicitAny) {
var diagnostic = (<VariableDeclaration>symbol.valueDeclaration).type ?
Diagnostics._0_implicitly_has_type_any_because_it_is_referenced_directly_or_indirectly_in_its_own_type_annotation :
Diagnostics._0_implicitly_has_type_any_because_it_is_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer;
error(symbol.valueDeclaration, diagnostic, symbolToString(symbol));
}
}
return links.type;
}
function getSetAccessorTypeAnnotationNode(accessor: AccessorDeclaration): TypeNode | LiteralExpression {
return accessor && accessor.parameters.length > 0 && accessor.parameters[0].type;
}
function getAnnotatedAccessorType(accessor: AccessorDeclaration): Type {
if (accessor) {
if (accessor.kind === SyntaxKind.GetAccessor) {
return accessor.type && getTypeFromTypeNode(accessor.type);
}
else {
var setterTypeAnnotation = getSetAccessorTypeAnnotationNode(accessor);
return setterTypeAnnotation && getTypeFromTypeNode(setterTypeAnnotation);
}
}
return undefined;
}
function getTypeOfAccessors(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
checkAndStoreTypeOfAccessors(symbol, links);
return links.type;
}
function checkAndStoreTypeOfAccessors(symbol: Symbol, links?: SymbolLinks) {
links = links || getSymbolLinks(symbol);
if (!links.type) {
links.type = resolvingType;
var getter = <AccessorDeclaration>getDeclarationOfKind(symbol, SyntaxKind.GetAccessor);
var setter = <AccessorDeclaration>getDeclarationOfKind(symbol, SyntaxKind.SetAccessor);
var type: Type;
// First try to see if the user specified a return type on the get-accessor.
var getterReturnType = getAnnotatedAccessorType(getter);
if (getterReturnType) {
type = getterReturnType;
}
else {
// If the user didn't specify a return type, try to use the set-accessor's parameter type.
var setterParameterType = getAnnotatedAccessorType(setter);
if (setterParameterType) {
type = setterParameterType;
}
else {
// If there are no specified types, try to infer it from the body of the get accessor if it exists.
if (getter && getter.body) {
type = getReturnTypeFromBody(getter);
}
// Otherwise, fall back to 'any'.
else {
if (compilerOptions.noImplicitAny) {
error(setter, Diagnostics.Property_0_implicitly_has_type_any_because_its_set_accessor_lacks_a_type_annotation, symbolToString(symbol));
}
type = anyType;
}
}
}
if (links.type === resolvingType) {
links.type = type;
}
}
else if (links.type === resolvingType) {
links.type = anyType;
if (compilerOptions.noImplicitAny) {
var getter = <AccessorDeclaration>getDeclarationOfKind(symbol, SyntaxKind.GetAccessor);
error(getter, Diagnostics._0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions, symbolToString(symbol));
}
}
}
function getTypeOfFuncClassEnumModule(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.type) {
links.type = createObjectType(TypeFlags.Anonymous, symbol);
}
return links.type;
}
function getTypeOfEnumMember(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.type) {
links.type = getDeclaredTypeOfEnum(getParentOfSymbol(symbol));
}
return links.type;
}
function getTypeOfImport(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.type) {
links.type = getTypeOfSymbol(resolveImport(symbol));
}
return links.type;
}
function getTypeOfInstantiatedSymbol(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.type) {
links.type = instantiateType(getTypeOfSymbol(links.target), links.mapper);
}
return links.type;
}
function getTypeOfSymbol(symbol: Symbol): Type {
if (symbol.flags & SymbolFlags.Instantiated) {
return getTypeOfInstantiatedSymbol(symbol);
}
if (symbol.flags & (SymbolFlags.Variable | SymbolFlags.Property)) {
return getTypeOfVariableOrParameterOrProperty(symbol);
}
if (symbol.flags & (SymbolFlags.Function | SymbolFlags.Method | SymbolFlags.Class | SymbolFlags.Enum | SymbolFlags.ValueModule)) {
return getTypeOfFuncClassEnumModule(symbol);
}
if (symbol.flags & SymbolFlags.EnumMember) {
return getTypeOfEnumMember(symbol);
}
if (symbol.flags & SymbolFlags.Accessor) {
return getTypeOfAccessors(symbol);
}
if (symbol.flags & SymbolFlags.Import) {
return getTypeOfImport(symbol);
}
return unknownType;
}
function getTargetType(type: ObjectType): Type {
return type.flags & TypeFlags.Reference ? (<TypeReference>type).target : type;
}
function hasBaseType(type: InterfaceType, checkBase: InterfaceType) {
return check(type);
function check(type: InterfaceType): boolean {
var target = <InterfaceType>getTargetType(type);
return target === checkBase || forEach(target.baseTypes, check);
}
}
// Return combined list of type parameters from all declarations of a class or interface. Elsewhere we check they're all
// the same, but even if they're not we still need the complete list to ensure instantiations supply type arguments
// for all type parameters.
function getTypeParametersOfClassOrInterface(symbol: Symbol): TypeParameter[] {
var result: TypeParameter[];
forEach(symbol.declarations, node => {
if (node.kind === SyntaxKind.InterfaceDeclaration || node.kind === SyntaxKind.ClassDeclaration) {
var declaration = <InterfaceDeclaration>node;
if (declaration.typeParameters && declaration.typeParameters.length) {
forEach(declaration.typeParameters, node => {
var tp = getDeclaredTypeOfTypeParameter(getSymbolOfNode(node));
if (!result) {
result = [tp];
}
else if (!contains(result, tp)) {
result.push(tp);
}
});
}
}
});
return result;
}
function getDeclaredTypeOfClass(symbol: Symbol): InterfaceType {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
var type = links.declaredType = <InterfaceType>createObjectType(TypeFlags.Class, symbol);
var typeParameters = getTypeParametersOfClassOrInterface(symbol);
if (typeParameters) {
type.flags |= TypeFlags.Reference;
type.typeParameters = typeParameters;
(<GenericType>type).instantiations = {};
(<GenericType>type).instantiations[getTypeListId(type.typeParameters)] = <GenericType>type;
(<GenericType>type).target = <GenericType>type;
(<GenericType>type).typeArguments = type.typeParameters;
}
type.baseTypes = [];
var declaration = <ClassDeclaration>getDeclarationOfKind(symbol, SyntaxKind.ClassDeclaration);
var baseTypeNode = getClassBaseTypeNode(declaration);
if (baseTypeNode) {
var baseType = getTypeFromTypeReferenceNode(baseTypeNode);
if (baseType !== unknownType) {
if (getTargetType(baseType).flags & TypeFlags.Class) {
if (type !== baseType && !hasBaseType(<InterfaceType>baseType, type)) {
type.baseTypes.push(baseType);
}
else {
error(declaration, Diagnostics.Type_0_recursively_references_itself_as_a_base_type, typeToString(type, /*enclosingDeclaration*/ undefined, TypeFormatFlags.WriteArrayAsGenericType));
}
}
else {
error(baseTypeNode, Diagnostics.A_class_may_only_extend_another_class);
}
}
}
type.declaredProperties = getNamedMembers(symbol.members);
type.declaredCallSignatures = emptyArray;
type.declaredConstructSignatures = emptyArray;
type.declaredStringIndexType = getIndexTypeOfSymbol(symbol, IndexKind.String);
type.declaredNumberIndexType = getIndexTypeOfSymbol(symbol, IndexKind.Number);
}
return <InterfaceType>links.declaredType;
}
function getDeclaredTypeOfInterface(symbol: Symbol): InterfaceType {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
var type = links.declaredType = <InterfaceType>createObjectType(TypeFlags.Interface, symbol);
var typeParameters = getTypeParametersOfClassOrInterface(symbol);
if (typeParameters) {
type.flags |= TypeFlags.Reference;
type.typeParameters = typeParameters;
(<GenericType>type).instantiations = {};
(<GenericType>type).instantiations[getTypeListId(type.typeParameters)] = <GenericType>type;
(<GenericType>type).target = <GenericType>type;
(<GenericType>type).typeArguments = type.typeParameters;
}
type.baseTypes = [];
forEach(symbol.declarations, declaration => {
if (declaration.kind === SyntaxKind.InterfaceDeclaration && getInterfaceBaseTypeNodes(<InterfaceDeclaration>declaration)) {
forEach(getInterfaceBaseTypeNodes(<InterfaceDeclaration>declaration), node => {
var baseType = getTypeFromTypeReferenceNode(node);
if (baseType !== unknownType) {
if (getTargetType(baseType).flags & (TypeFlags.Class | TypeFlags.Interface)) {
if (type !== baseType && !hasBaseType(<InterfaceType>baseType, type)) {
type.baseTypes.push(baseType);
}
else {
error(declaration, Diagnostics.Type_0_recursively_references_itself_as_a_base_type, typeToString(type, /*enclosingDeclaration*/ undefined, TypeFormatFlags.WriteArrayAsGenericType));
}
}
else {
error(node, Diagnostics.An_interface_may_only_extend_a_class_or_another_interface);
}
}
});
}
});
type.declaredProperties = getNamedMembers(symbol.members);
type.declaredCallSignatures = getSignaturesOfSymbol(symbol.members["__call"]);
type.declaredConstructSignatures = getSignaturesOfSymbol(symbol.members["__new"]);
type.declaredStringIndexType = getIndexTypeOfSymbol(symbol, IndexKind.String);
type.declaredNumberIndexType = getIndexTypeOfSymbol(symbol, IndexKind.Number);
}
return <InterfaceType>links.declaredType;
}
function getDeclaredTypeOfTypeAlias(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
links.declaredType = resolvingType;
var declaration = <TypeAliasDeclaration>getDeclarationOfKind(symbol, SyntaxKind.TypeAliasDeclaration);
var type = getTypeFromTypeNode(declaration.type);
if (links.declaredType === resolvingType) {
links.declaredType = type;
}
}
else if (links.declaredType === resolvingType) {
links.declaredType = unknownType;
var declaration = <TypeAliasDeclaration>getDeclarationOfKind(symbol, SyntaxKind.TypeAliasDeclaration);
error(declaration.name, Diagnostics.Type_alias_0_circularly_references_itself, symbolToString(symbol));
}
return links.declaredType;
}
function getDeclaredTypeOfEnum(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
var type = createType(TypeFlags.Enum);
type.symbol = symbol;
links.declaredType = type;
}
return links.declaredType;
}
function getDeclaredTypeOfTypeParameter(symbol: Symbol): TypeParameter {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
var type = <TypeParameter>createType(TypeFlags.TypeParameter);
type.symbol = symbol;
if (!(<TypeParameterDeclaration>getDeclarationOfKind(symbol, SyntaxKind.TypeParameter)).constraint) {
type.constraint = noConstraintType;
}
links.declaredType = type;
}
return <TypeParameter>links.declaredType;
}
function getDeclaredTypeOfImport(symbol: Symbol): Type {
var links = getSymbolLinks(symbol);
if (!links.declaredType) {
links.declaredType = getDeclaredTypeOfSymbol(resolveImport(symbol));
}
return links.declaredType;
}
function getDeclaredTypeOfSymbol(symbol: Symbol): Type {
Debug.assert((symbol.flags & SymbolFlags.Instantiated) === 0);
if (symbol.flags & SymbolFlags.Class) {
return getDeclaredTypeOfClass(symbol);
}
if (symbol.flags & SymbolFlags.Interface) {
return getDeclaredTypeOfInterface(symbol);
}
if (symbol.flags & SymbolFlags.TypeAlias) {
return getDeclaredTypeOfTypeAlias(symbol);
}
if (symbol.flags & SymbolFlags.Enum) {
return getDeclaredTypeOfEnum(symbol);
}
if (symbol.flags & SymbolFlags.TypeParameter) {
return getDeclaredTypeOfTypeParameter(symbol);
}
if (symbol.flags & SymbolFlags.Import) {
return getDeclaredTypeOfImport(symbol);
}
return unknownType;
}
function createSymbolTable(symbols: Symbol[]): SymbolTable {
var result: SymbolTable = {};
for (var i = 0; i < symbols.length; i++) {
var symbol = symbols[i];
result[symbol.name] = symbol;
}
return result;
}
function createInstantiatedSymbolTable(symbols: Symbol[], mapper: TypeMapper): SymbolTable {
var result: SymbolTable = {};
for (var i = 0; i < symbols.length; i++) {
var symbol = symbols[i];
result[symbol.name] = instantiateSymbol(symbol, mapper);
}
return result;
}
function addInheritedMembers(symbols: SymbolTable, baseSymbols: Symbol[]) {
for (var i = 0; i < baseSymbols.length; i++) {
var s = baseSymbols[i];
if (!hasProperty(symbols, s.name)) {
symbols[s.name] = s;
}
}
}
function addInheritedSignatures(signatures: Signature[], baseSignatures: Signature[]) {
if (baseSignatures) {
for (var i = 0; i < baseSignatures.length; i++) {
signatures.push(baseSignatures[i]);
}
}
}
function resolveClassOrInterfaceMembers(type: InterfaceType): void {
var members = type.symbol.members;
var callSignatures = type.declaredCallSignatures;
var constructSignatures = type.declaredConstructSignatures;
var stringIndexType = type.declaredStringIndexType;
var numberIndexType = type.declaredNumberIndexType;
if (type.baseTypes.length) {
members = createSymbolTable(type.declaredProperties);
forEach(type.baseTypes, baseType => {
addInheritedMembers(members, getPropertiesOfObjectType(baseType));
callSignatures = concatenate(callSignatures, getSignaturesOfType(baseType, SignatureKind.Call));
constructSignatures = concatenate(constructSignatures, getSignaturesOfType(baseType, SignatureKind.Construct));
stringIndexType = stringIndexType || getIndexTypeOfType(baseType, IndexKind.String);
numberIndexType = numberIndexType || getIndexTypeOfType(baseType, IndexKind.Number);
});
}
setObjectTypeMembers(type, members, callSignatures, constructSignatures, stringIndexType, numberIndexType);
}
function resolveTypeReferenceMembers(type: TypeReference): void {
var target = type.target;
var mapper = createTypeMapper(target.typeParameters, type.typeArguments);
var members = createInstantiatedSymbolTable(target.declaredProperties, mapper);
var callSignatures = instantiateList(target.declaredCallSignatures, mapper, instantiateSignature);
var constructSignatures = instantiateList(target.declaredConstructSignatures, mapper, instantiateSignature);
var stringIndexType = target.declaredStringIndexType ? instantiateType(target.declaredStringIndexType, mapper) : undefined;
var numberIndexType = target.declaredNumberIndexType ? instantiateType(target.declaredNumberIndexType, mapper) : undefined;
forEach(target.baseTypes, baseType => {
var instantiatedBaseType = instantiateType(baseType, mapper);
addInheritedMembers(members, getPropertiesOfObjectType(instantiatedBaseType));
callSignatures = concatenate(callSignatures, getSignaturesOfType(instantiatedBaseType, SignatureKind.Call));
constructSignatures = concatenate(constructSignatures, getSignaturesOfType(instantiatedBaseType, SignatureKind.Construct));
stringIndexType = stringIndexType || getIndexTypeOfType(instantiatedBaseType, IndexKind.String);
numberIndexType = numberIndexType || getIndexTypeOfType(instantiatedBaseType, IndexKind.Number);
});
setObjectTypeMembers(type, members, callSignatures, constructSignatures, stringIndexType, numberIndexType);
}
function createSignature(declaration: SignatureDeclaration, typeParameters: TypeParameter[], parameters: Symbol[],
resolvedReturnType: Type, minArgumentCount: number, hasRestParameter: boolean, hasStringLiterals: boolean): Signature {
var sig = new Signature(checker);
sig.declaration = declaration;
sig.typeParameters = typeParameters;
sig.parameters = parameters;
sig.resolvedReturnType = resolvedReturnType;
sig.minArgumentCount = minArgumentCount;
sig.hasRestParameter = hasRestParameter;
sig.hasStringLiterals = hasStringLiterals;
return sig;
}
function cloneSignature(sig: Signature): Signature {
return createSignature(sig.declaration, sig.typeParameters, sig.parameters, sig.resolvedReturnType,
sig.minArgumentCount, sig.hasRestParameter, sig.hasStringLiterals);
}
function getDefaultConstructSignatures(classType: InterfaceType): Signature[] {
if (classType.baseTypes.length) {
var baseType = classType.baseTypes[0];
var baseSignatures = getSignaturesOfType(getTypeOfSymbol(baseType.symbol), SignatureKind.Construct);
return map(baseSignatures, baseSignature => {
var signature = baseType.flags & TypeFlags.Reference ?
getSignatureInstantiation(baseSignature, (<TypeReference>baseType).typeArguments) : cloneSignature(baseSignature);
signature.typeParameters = classType.typeParameters;
signature.resolvedReturnType = classType;
return signature;
});
}
return [createSignature(undefined, classType.typeParameters, emptyArray, classType, 0, false, false)];
}
function createTupleTypeMemberSymbols(memberTypes: Type[]): SymbolTable {
var members: SymbolTable = {};
for (var i = 0; i < memberTypes.length; i++) {
var symbol = <TransientSymbol>createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "" + i);
symbol.type = memberTypes[i];
members[i] = symbol;
}
return members;
}
function resolveTupleTypeMembers(type: TupleType) {
var arrayType = resolveObjectOrUnionTypeMembers(createArrayType(getUnionType(type.elementTypes)));
var members = createTupleTypeMemberSymbols(type.elementTypes);
addInheritedMembers(members, arrayType.properties);
setObjectTypeMembers(type, members, arrayType.callSignatures, arrayType.constructSignatures, arrayType.stringIndexType, arrayType.numberIndexType);
}
function signatureListsIdentical(s: Signature[], t: Signature[]): boolean {
if (s.length !== t.length) {
return false;
}
for (var i = 0; i < s.length; i++) {
if (!compareSignatures(s[i], t[i], /*compareReturnTypes*/ false, compareTypes)) {
return false;
}
}
return true;
}
// If the lists of call or construct signatures in the given types are all identical except for return types,
// and if none of the signatures are generic, return a list of signatures that has substitutes a union of the
// return types of the corresponding signatures in each resulting signature.
function getUnionSignatures(types: Type[], kind: SignatureKind): Signature[] {
var signatureLists = map(types, t => getSignaturesOfType(t, kind));
var signatures = signatureLists[0];
for (var i = 0; i < signatures.length; i++) {
if (signatures[i].typeParameters) {
return emptyArray;
}
}
for (var i = 1; i < signatureLists.length; i++) {
if (!signatureListsIdentical(signatures, signatureLists[i])) {
return emptyArray;
}
}
var result = map(signatures, cloneSignature);
for (var i = 0; i < result.length; i++) {
var s = result[i];
// Clear resolved return type we possibly got from cloneSignature
s.resolvedReturnType = undefined;
s.unionSignatures = map(signatureLists, signatures => signatures[i]);
}
return result;
}
function getUnionIndexType(types: Type[], kind: IndexKind): Type {
var indexTypes: Type[] = [];
for (var i = 0; i < types.length; i++) {
var indexType = getIndexTypeOfType(types[i], kind);
if (!indexType) {
return undefined;
}
indexTypes.push(indexType);
}
return getUnionType(indexTypes);
}
function resolveUnionTypeMembers(type: UnionType) {
// The members and properties collections are empty for union types. To get all properties of a union
// type use getPropertiesOfType (only the language service uses this).
var callSignatures = getUnionSignatures(type.types, SignatureKind.Call);
var constructSignatures = getUnionSignatures(type.types, SignatureKind.Construct);
var stringIndexType = getUnionIndexType(type.types, IndexKind.String);
var numberIndexType = getUnionIndexType(type.types, IndexKind.Number);
setObjectTypeMembers(type, emptySymbols, callSignatures, constructSignatures, stringIndexType, numberIndexType);
}
function resolveAnonymousTypeMembers(type: ObjectType) {
var symbol = type.symbol;
if (symbol.flags & SymbolFlags.TypeLiteral) {
var members = symbol.members;
var callSignatures = getSignaturesOfSymbol(members["__call"]);
var constructSignatures = getSignaturesOfSymbol(members["__new"]);
var stringIndexType = getIndexTypeOfSymbol(symbol, IndexKind.String);
var numberIndexType = getIndexTypeOfSymbol(symbol, IndexKind.Number);
}
else {
// Combinations of function, class, enum and module
var members = emptySymbols;
var callSignatures: Signature[] = emptyArray;
var constructSignatures: Signature[] = emptyArray;
if (symbol.flags & SymbolFlags.HasExports) {
members = symbol.exports;
}
if (symbol.flags & (SymbolFlags.Function | SymbolFlags.Method)) {
callSignatures = getSignaturesOfSymbol(symbol);
}
if (symbol.flags & SymbolFlags.Class) {
var classType = getDeclaredTypeOfClass(symbol);
constructSignatures = getSignaturesOfSymbol(symbol.members["__constructor"]);
if (!constructSignatures.length) {
constructSignatures = getDefaultConstructSignatures(classType);
}
if (classType.baseTypes.length) {
members = createSymbolTable(getNamedMembers(members));
addInheritedMembers(members, getPropertiesOfObjectType(getTypeOfSymbol(classType.baseTypes[0].symbol)));
}
}
var stringIndexType: Type = undefined;
var numberIndexType: Type = (symbol.flags & SymbolFlags.Enum) ? stringType : undefined;
}
setObjectTypeMembers(type, members, callSignatures, constructSignatures, stringIndexType, numberIndexType);
}
function resolveObjectOrUnionTypeMembers(type: ObjectType): ResolvedType {
if (!(<ResolvedType>type).members) {
if (type.flags & (TypeFlags.Class | TypeFlags.Interface)) {
resolveClassOrInterfaceMembers(<InterfaceType>type);
}
else if (type.flags & TypeFlags.Anonymous) {
resolveAnonymousTypeMembers(<ObjectType>type);
}
else if (type.flags & TypeFlags.Tuple) {
resolveTupleTypeMembers(<TupleType>type);
}
else if (type.flags & TypeFlags.Union) {
resolveUnionTypeMembers(<UnionType>type);
}
else {
resolveTypeReferenceMembers(<TypeReference>type);
}
}
return <ResolvedType>type;
}
// Return properties of an object type or an empty array for other types
function getPropertiesOfObjectType(type: Type): Symbol[] {
if (type.flags & TypeFlags.ObjectType) {
return resolveObjectOrUnionTypeMembers(<ObjectType>type).properties;
}
return emptyArray;
}
// If the given type is an object type and that type has a property by the given name, return
// the symbol for that property. Otherwise return undefined.
function getPropertyOfObjectType(type: Type, name: string): Symbol {
if (type.flags & TypeFlags.ObjectType) {
var resolved = resolveObjectOrUnionTypeMembers(<ObjectType>type);
if (hasProperty(resolved.members, name)) {
var symbol = resolved.members[name];
if (symbolIsValue(symbol)) {
return symbol;
}
}
}
}
function getPropertiesOfUnionType(type: UnionType): Symbol[] {
var result: Symbol[] = [];
forEach(getPropertiesOfType(type.types[0]), prop => {
var unionProp = getPropertyOfUnionType(type, prop.name);
if (unionProp) {
result.push(unionProp);
}
});
return result;
}
function getPropertiesOfType(type: Type): Symbol[] {
if (type.flags & TypeFlags.Union) {
return getPropertiesOfUnionType(<UnionType>type);
}
return getPropertiesOfObjectType(getApparentType(type));
}
// For a type parameter, return the base constraint of the type parameter. For the string, number, and
// boolean primitive types, return the corresponding object types.Otherwise return the type itself.
// Note that the apparent type of a union type is the union type itself.
function getApparentType(type: Type): Type {
if (type.flags & TypeFlags.TypeParameter) {
do {
type = getConstraintOfTypeParameter(<TypeParameter>type);
} while (type && type.flags & TypeFlags.TypeParameter);
if (!type) {
type = emptyObjectType;
}
}
if (type.flags & TypeFlags.StringLike) {
type = globalStringType;
}
else if (type.flags & TypeFlags.NumberLike) {
type = globalNumberType;
}
else if (type.flags & TypeFlags.Boolean) {
type = globalBooleanType;
}
return type;
}
function createUnionProperty(unionType: UnionType, name: string): Symbol {
var types = unionType.types;
var props: Symbol[];
for (var i = 0; i < types.length; i++) {
var type = getApparentType(types[i]);
if (type !== unknownType) {
var prop = getPropertyOfType(type, name);
if (!prop) {
return undefined;
}
if (!props) {
props = [prop];
}
else {
props.push(prop);
}
}
}
var propTypes: Type[] = [];
var declarations: Declaration[] = [];
for (var i = 0; i < props.length; i++) {
var prop = props[i];
if (prop.declarations) {
declarations.push.apply(declarations, prop.declarations);
}
propTypes.push(getTypeOfSymbol(prop));
}
var result = <TransientSymbol>createSymbol(SymbolFlags.Property | SymbolFlags.Transient | SymbolFlags.UnionProperty, name);
result.unionType = unionType;
result.declarations = declarations;
result.type = getUnionType(propTypes);
return result;
}
function getPropertyOfUnionType(type: UnionType, name: string): Symbol {
var properties = type.resolvedProperties || (type.resolvedProperties = {});
if (hasProperty(properties, name)) {
return properties[name];
}
var property = createUnionProperty(type, name);
if (property) {
properties[name] = property;
}
return property;
}
// Return the symbol for the property with the given name in the given type. Creates synthetic union properties when
// necessary, maps primitive types and type parameters are to their apparent types, and augments with properties from
// Object and Function as appropriate.
function getPropertyOfType(type: Type, name: string): Symbol {
if (type.flags & TypeFlags.Union) {
return getPropertyOfUnionType(<UnionType>type, name);
}
if (!(type.flags & TypeFlags.ObjectType)) {
type = getApparentType(type);
if (!(type.flags & TypeFlags.ObjectType)) {
return undefined;
}
}
var resolved = resolveObjectOrUnionTypeMembers(type);
if (hasProperty(resolved.members, name)) {
var symbol = resolved.members[name];
if (symbolIsValue(symbol)) {
return symbol;
}
}
if (resolved === anyFunctionType || resolved.callSignatures.length || resolved.constructSignatures.length) {
var symbol = getPropertyOfObjectType(globalFunctionType, name);
if (symbol) return symbol;
}
return getPropertyOfObjectType(globalObjectType, name);
}
function getSignaturesOfObjectOrUnionType(type: Type, kind: SignatureKind): Signature[] {
if (type.flags & (TypeFlags.ObjectType | TypeFlags.Union)) {
var resolved = resolveObjectOrUnionTypeMembers(<ObjectType>type);
return kind === SignatureKind.Call ? resolved.callSignatures : resolved.constructSignatures;
}
return emptyArray;
}
// Return the signatures of the given kind in the given type. Creates synthetic union signatures when necessary and
// maps primitive types and type parameters are to their apparent types.
function getSignaturesOfType(type: Type, kind: SignatureKind): Signature[] {
return getSignaturesOfObjectOrUnionType(getApparentType(type), kind);
}
function getIndexTypeOfObjectOrUnionType(type: Type, kind: IndexKind): Type {
if (type.flags & (TypeFlags.ObjectType | TypeFlags.Union)) {
var resolved = resolveObjectOrUnionTypeMembers(<ObjectType>type);
return kind === IndexKind.String ? resolved.stringIndexType : resolved.numberIndexType;
}
}
// Return the index type of the given kind in the given type. Creates synthetic union index types when necessary and
// maps primitive types and type parameters are to their apparent types.
function getIndexTypeOfType(type: Type, kind: IndexKind): Type {
return getIndexTypeOfObjectOrUnionType(getApparentType(type), kind);
}
// Return list of type parameters with duplicates removed (duplicate identifier errors are generated in the actual
// type checking functions).
function getTypeParametersFromDeclaration(typeParameterDeclarations: TypeParameterDeclaration[]): TypeParameter[] {
var result: TypeParameter[] = [];
forEach(typeParameterDeclarations, node => {
var tp = getDeclaredTypeOfTypeParameter(node.symbol);
if (!contains(result, tp)) {
result.push(tp);
}
});
return result;
}
function getSignatureFromDeclaration(declaration: SignatureDeclaration): Signature {
var links = getNodeLinks(declaration);
if (!links.resolvedSignature) {
var classType = declaration.kind === SyntaxKind.Constructor ? getDeclaredTypeOfClass((<ClassDeclaration>declaration.parent).symbol) : undefined;
var typeParameters = classType ? classType.typeParameters :
declaration.typeParameters ? getTypeParametersFromDeclaration(declaration.typeParameters) : undefined;
var parameters: Symbol[] = [];
var hasStringLiterals = false;
var minArgumentCount = -1;
for (var i = 0, n = declaration.parameters.length; i < n; i++) {
var param = declaration.parameters[i];
parameters.push(param.symbol);
if (param.type && param.type.kind === SyntaxKind.StringLiteral) {
hasStringLiterals = true;
}
if (minArgumentCount < 0) {
if (param.initializer || param.questionToken || param.dotDotDotToken) {
minArgumentCount = i;
}
}
}
if (minArgumentCount < 0) {
minArgumentCount = declaration.parameters.length;
}
var returnType: Type;
if (classType) {
returnType = classType;
}
else if (declaration.type) {
returnType = getTypeFromTypeNode(declaration.type);
}
else {
// TypeScript 1.0 spec (April 2014):
// If only one accessor includes a type annotation, the other behaves as if it had the same type annotation.
if (declaration.kind === SyntaxKind.GetAccessor && !hasComputedNameButNotSymbol(declaration)) {
var setter = <AccessorDeclaration>getDeclarationOfKind(declaration.symbol, SyntaxKind.SetAccessor);
returnType = getAnnotatedAccessorType(setter);
}
if (!returnType && !(<FunctionLikeDeclaration>declaration).body) {
returnType = anyType;
}
}
links.resolvedSignature = createSignature(declaration, typeParameters, parameters, returnType,
minArgumentCount, hasRestParameters(declaration), hasStringLiterals);
}
return links.resolvedSignature;
}
function getSignaturesOfSymbol(symbol: Symbol): Signature[] {
if (!symbol) return emptyArray;
var result: Signature[] = [];
for (var i = 0, len = symbol.declarations.length; i < len; i++) {
var node = symbol.declarations[i];
switch (node.kind) {
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.Method:
case SyntaxKind.Constructor:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
// Don't include signature if node is the implementation of an overloaded function. A node is considered
// an implementation node if it has a body and the previous node is of the same kind and immediately
// precedes the implementation node (i.e. has the same parent and ends where the implementation starts).
if (i > 0 && (<FunctionLikeDeclaration>node).body) {
var previous = symbol.declarations[i - 1];
if (node.parent === previous.parent && node.kind === previous.kind && node.pos === previous.end) {
break;
}
}
result.push(getSignatureFromDeclaration(<SignatureDeclaration>node));
}
}
return result;
}
function getReturnTypeOfSignature(signature: Signature): Type {
if (!signature.resolvedReturnType) {
signature.resolvedReturnType = resolvingType;
if (signature.target) {
var type = instantiateType(getReturnTypeOfSignature(signature.target), signature.mapper);
}
else if (signature.unionSignatures) {
var type = getUnionType(map(signature.unionSignatures, getReturnTypeOfSignature));
}
else {
var type = getReturnTypeFromBody(<FunctionLikeDeclaration>signature.declaration);
}
if (signature.resolvedReturnType === resolvingType) {
signature.resolvedReturnType = type;
}
}
else if (signature.resolvedReturnType === resolvingType) {
signature.resolvedReturnType = anyType;
if (compilerOptions.noImplicitAny) {
var declaration = <Declaration>signature.declaration;
if (declaration.name) {
error(declaration.name, Diagnostics._0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions, declarationNameToString(declaration.name));
}
else {
error(declaration, Diagnostics.Function_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions);
}
}
}
return signature.resolvedReturnType;
}
function getRestTypeOfSignature(signature: Signature): Type {
if (signature.hasRestParameter) {
var type = getTypeOfSymbol(signature.parameters[signature.parameters.length - 1]);
if (type.flags & TypeFlags.Reference && (<TypeReference>type).target === globalArrayType) {
return (<TypeReference>type).typeArguments[0];
}
}
return anyType;
}
function getSignatureInstantiation(signature: Signature, typeArguments: Type[]): Signature {
return instantiateSignature(signature, createTypeMapper(signature.typeParameters, typeArguments), true);
}
function getErasedSignature(signature: Signature): Signature {
if (!signature.typeParameters) return signature;
if (!signature.erasedSignatureCache) {
if (signature.target) {
signature.erasedSignatureCache = instantiateSignature(getErasedSignature(signature.target), signature.mapper);
}
else {
signature.erasedSignatureCache = instantiateSignature(signature, createTypeEraser(signature.typeParameters), true);
}
}
return signature.erasedSignatureCache;
}
function getOrCreateTypeFromSignature(signature: Signature): ObjectType {
// There are two ways to declare a construct signature, one is by declaring a class constructor
// using the constructor keyword, and the other is declaring a bare construct signature in an
// object type literal or interface (using the new keyword). Each way of declaring a constructor
// will result in a different declaration kind.
if (!signature.isolatedSignatureType) {
var isConstructor = signature.declaration.kind === SyntaxKind.Constructor || signature.declaration.kind === SyntaxKind.ConstructSignature;
var type = <ResolvedType>createObjectType(TypeFlags.Anonymous | TypeFlags.FromSignature);
type.members = emptySymbols;
type.properties = emptyArray;
type.callSignatures = !isConstructor ? [signature] : emptyArray;
type.constructSignatures = isConstructor ? [signature] : emptyArray;
signature.isolatedSignatureType = type;
}
return signature.isolatedSignatureType;
}
function getIndexSymbol(symbol: Symbol): Symbol {
return symbol.members["__index"];
}
function getIndexDeclarationOfSymbol(symbol: Symbol, kind: IndexKind): SignatureDeclaration {
var syntaxKind = kind === IndexKind.Number ? SyntaxKind.NumberKeyword : SyntaxKind.StringKeyword;
var indexSymbol = getIndexSymbol(symbol);
if (indexSymbol) {
var len = indexSymbol.declarations.length;
for (var i = 0; i < len; i++) {
var node = <SignatureDeclaration>indexSymbol.declarations[i];
if (node.parameters.length === 1) {
var parameter = node.parameters[0];
if (parameter && parameter.type && parameter.type.kind === syntaxKind) {
return node;
}
}
}
}
return undefined;
}
function getIndexTypeOfSymbol(symbol: Symbol, kind: IndexKind): Type {
var declaration = getIndexDeclarationOfSymbol(symbol, kind);
return declaration
? declaration.type ? getTypeFromTypeNode(declaration.type) : anyType
: undefined;
}
function getConstraintOfTypeParameter(type: TypeParameter): Type {
if (!type.constraint) {
if (type.target) {
var targetConstraint = getConstraintOfTypeParameter(type.target);
type.constraint = targetConstraint ? instantiateType(targetConstraint, type.mapper) : noConstraintType;
}
else {
type.constraint = getTypeFromTypeNode((<TypeParameterDeclaration>getDeclarationOfKind(type.symbol, SyntaxKind.TypeParameter)).constraint);
}
}
return type.constraint === noConstraintType ? undefined : type.constraint;
}
function getTypeListId(types: Type[]) {
switch (types.length) {
case 1:
return "" + types[0].id;
case 2:
return types[0].id + "," + types[1].id;
default:
var result = "";
for (var i = 0; i < types.length; i++) {
if (i > 0) result += ",";
result += types[i].id;
}
return result;
}
}
function createTypeReference(target: GenericType, typeArguments: Type[]): TypeReference {
var id = getTypeListId(typeArguments);
var type = target.instantiations[id];
if (!type) {
type = target.instantiations[id] = <TypeReference>createObjectType(TypeFlags.Reference, target.symbol);
type.target = target;
type.typeArguments = typeArguments;
}
return type;
}
function isTypeParameterReferenceIllegalInConstraint(typeReferenceNode: TypeReferenceNode, typeParameterSymbol: Symbol): boolean {
var links = getNodeLinks(typeReferenceNode);
if (links.isIllegalTypeReferenceInConstraint !== undefined) {
return links.isIllegalTypeReferenceInConstraint;
}
// bubble up to the declaration
var currentNode: Node = typeReferenceNode;
// forEach === exists
while (!forEach(typeParameterSymbol.declarations, d => d.parent === currentNode.parent)) {
currentNode = currentNode.parent;
}
// if last step was made from the type parameter this means that path has started somewhere in constraint which is illegal
links.isIllegalTypeReferenceInConstraint = currentNode.kind === SyntaxKind.TypeParameter;
return links.isIllegalTypeReferenceInConstraint;
}
function checkTypeParameterHasIllegalReferencesInConstraint(typeParameter: TypeParameterDeclaration): void {
var typeParameterSymbol: Symbol;
function check(n: Node): void {
if (n.kind === SyntaxKind.TypeReference && (<TypeReferenceNode>n).typeName.kind === SyntaxKind.Identifier) {
var links = getNodeLinks(n);
if (links.isIllegalTypeReferenceInConstraint === undefined) {
var symbol = resolveName(typeParameter, (<Identifier>(<TypeReferenceNode>n).typeName).text, SymbolFlags.Type, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined);
if (symbol && (symbol.flags & SymbolFlags.TypeParameter)) {
// TypeScript 1.0 spec (April 2014): 3.4.1
// Type parameters declared in a particular type parameter list
// may not be referenced in constraints in that type parameter list
// symbol.declaration.parent === typeParameter.parent
// -> typeParameter and symbol.declaration originate from the same type parameter list
// -> illegal for all declarations in symbol
// forEach === exists
links.isIllegalTypeReferenceInConstraint = forEach(symbol.declarations, d => d.parent == typeParameter.parent);
}
}
if (links.isIllegalTypeReferenceInConstraint) {
error(typeParameter, Diagnostics.Constraint_of_a_type_parameter_cannot_reference_any_type_parameter_from_the_same_type_parameter_list);
}
}
forEachChild(n, check);
}
if (typeParameter.constraint) {
typeParameterSymbol = getSymbolOfNode(typeParameter);
check(typeParameter.constraint);
}
}
function getTypeFromTypeReferenceNode(node: TypeReferenceNode): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
var symbol = resolveEntityName(node, node.typeName, SymbolFlags.Type);
if (symbol) {
var type: Type;
if ((symbol.flags & SymbolFlags.TypeParameter) && isTypeParameterReferenceIllegalInConstraint(node, symbol)) {
// TypeScript 1.0 spec (April 2014): 3.4.1
// Type parameters declared in a particular type parameter list
// may not be referenced in constraints in that type parameter list
// Implementation: such type references are resolved to 'unknown' type that usually denotes error
type = unknownType;
}
else {
type = getDeclaredTypeOfSymbol(symbol);
if (type.flags & (TypeFlags.Class | TypeFlags.Interface) && type.flags & TypeFlags.Reference) {
var typeParameters = (<InterfaceType>type).typeParameters;
if (node.typeArguments && node.typeArguments.length === typeParameters.length) {
type = createTypeReference(<GenericType>type, map(node.typeArguments, getTypeFromTypeNode));
}
else {
error(node, Diagnostics.Generic_type_0_requires_1_type_argument_s, typeToString(type, /*enclosingDeclaration*/ undefined, TypeFormatFlags.WriteArrayAsGenericType), typeParameters.length);
type = undefined;
}
}
else {
if (node.typeArguments) {
error(node, Diagnostics.Type_0_is_not_generic, typeToString(type));
type = undefined;
}
}
}
}
links.resolvedType = type || unknownType;
}
return links.resolvedType;
}
function getTypeFromTypeQueryNode(node: TypeQueryNode): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
// TypeScript 1.0 spec (April 2014): 3.6.3
// The expression is processed as an identifier expression (section 4.3)
// or property access expression(section 4.10),
// the widened type(section 3.9) of which becomes the result.
links.resolvedType = getWidenedType(checkExpression(node.exprName));
}
return links.resolvedType;
}
function getTypeOfGlobalSymbol(symbol: Symbol, arity: number): ObjectType {
function getTypeDeclaration(symbol: Symbol): Declaration {
var declarations = symbol.declarations;
for (var i = 0; i < declarations.length; i++) {
var declaration = declarations[i];
switch (declaration.kind) {
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.EnumDeclaration:
return declaration;
}
}
}
if (!symbol) {
return emptyObjectType;
}
var type = getDeclaredTypeOfSymbol(symbol);
if (!(type.flags & TypeFlags.ObjectType)) {
error(getTypeDeclaration(symbol), Diagnostics.Global_type_0_must_be_a_class_or_interface_type, symbol.name);
return emptyObjectType;
}
if (((<InterfaceType>type).typeParameters ? (<InterfaceType>type).typeParameters.length : 0) !== arity) {
error(getTypeDeclaration(symbol), Diagnostics.Global_type_0_must_have_1_type_parameter_s, symbol.name, arity);
return emptyObjectType;
}
return <ObjectType>type;
}
function getGlobalSymbol(name: string): Symbol {
return resolveName(undefined, name, SymbolFlags.Type, Diagnostics.Cannot_find_global_type_0, name);
}
function getGlobalType(name: string): ObjectType {
return getTypeOfGlobalSymbol(getGlobalSymbol(name), 0);
}
function createArrayType(elementType: Type): Type {
// globalArrayType will be undefined if we get here during creation of the Array type. This for example happens if
// user code augments the Array type with call or construct signatures that have an array type as the return type.
// We instead use globalArraySymbol to obtain the (not yet fully constructed) Array type.
var arrayType = globalArrayType || getDeclaredTypeOfSymbol(globalArraySymbol);
return arrayType !== emptyObjectType ? createTypeReference(<GenericType>arrayType, [elementType]) : emptyObjectType;
}
function getTypeFromArrayTypeNode(node: ArrayTypeNode): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
links.resolvedType = createArrayType(getTypeFromTypeNode(node.elementType));
}
return links.resolvedType;
}
function createTupleType(elementTypes: Type[]) {
var id = getTypeListId(elementTypes);
var type = tupleTypes[id];
if (!type) {
type = tupleTypes[id] = <TupleType>createObjectType(TypeFlags.Tuple);
type.elementTypes = elementTypes;
}
return type;
}
function getTypeFromTupleTypeNode(node: TupleTypeNode): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
links.resolvedType = createTupleType(map(node.elementTypes, getTypeFromTypeNode));
}
return links.resolvedType;
}
function addTypeToSortedSet(sortedSet: Type[], type: Type) {
if (type.flags & TypeFlags.Union) {
addTypesToSortedSet(sortedSet, (<UnionType>type).types);
}
else {
var i = 0;
var id = type.id;
while (i < sortedSet.length && sortedSet[i].id < id) {
i++;
}
if (i === sortedSet.length || sortedSet[i].id !== id) {
sortedSet.splice(i, 0, type);
}
}
}
function addTypesToSortedSet(sortedTypes: Type[], types: Type[]) {
for (var i = 0, len = types.length; i < len; i++) {
addTypeToSortedSet(sortedTypes, types[i]);
}
}
function isSubtypeOfAny(candidate: Type, types: Type[]): boolean {
for (var i = 0, len = types.length; i < len; i++) {
if (candidate !== types[i] && isTypeSubtypeOf(candidate, types[i])) {
return true;
}
}
return false;
}
function removeSubtypes(types: Type[]) {
var i = types.length;
while (i > 0) {
i--;
if (isSubtypeOfAny(types[i], types)) {
types.splice(i, 1);
}
}
}
function containsAnyType(types: Type[]) {
for (var i = 0; i < types.length; i++) {
if (types[i].flags & TypeFlags.Any) {
return true;
}
}
return false;
}
function removeAllButLast(types: Type[], typeToRemove: Type) {
var i = types.length;
while (i > 0 && types.length > 1) {
i--;
if (types[i] === typeToRemove) {
types.splice(i, 1);
}
}
}
function getUnionType(types: Type[], noSubtypeReduction?: boolean): Type {
if (types.length === 0) {
return emptyObjectType;
}
var sortedTypes: Type[] = [];
addTypesToSortedSet(sortedTypes, types);
if (noSubtypeReduction) {
if (containsAnyType(sortedTypes)) {
return anyType;
}
removeAllButLast(sortedTypes, undefinedType);
removeAllButLast(sortedTypes, nullType);
}
else {
removeSubtypes(sortedTypes);
}
if (sortedTypes.length === 1) {
return sortedTypes[0];
}
var id = getTypeListId(sortedTypes);
var type = unionTypes[id];
if (!type) {
type = unionTypes[id] = <UnionType>createObjectType(TypeFlags.Union);
type.types = sortedTypes;
}
return type;
}
function getTypeFromUnionTypeNode(node: UnionTypeNode): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
links.resolvedType = getUnionType(map(node.types, getTypeFromTypeNode), /*noSubtypeReduction*/ true);
}
return links.resolvedType;
}
function getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node: Node): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
// Deferred resolution of members is handled by resolveObjectTypeMembers
links.resolvedType = createObjectType(TypeFlags.Anonymous, node.symbol);
}
return links.resolvedType;
}
function getStringLiteralType(node: LiteralExpression): StringLiteralType {
if (hasProperty(stringLiteralTypes, node.text)) {
return stringLiteralTypes[node.text];
}
var type = stringLiteralTypes[node.text] = <StringLiteralType>createType(TypeFlags.StringLiteral);
type.text = getTextOfNode(node);
return type;
}
function getTypeFromStringLiteral(node: LiteralExpression): Type {
var links = getNodeLinks(node);
if (!links.resolvedType) {
links.resolvedType = getStringLiteralType(node);
}
return links.resolvedType;
}
function getTypeFromTypeNode(node: TypeNode | LiteralExpression): Type {
switch (node.kind) {
case SyntaxKind.AnyKeyword:
return anyType;
case SyntaxKind.StringKeyword:
return stringType;
case SyntaxKind.NumberKeyword:
return numberType;
case SyntaxKind.BooleanKeyword:
return booleanType;
case SyntaxKind.VoidKeyword:
return voidType;
case SyntaxKind.StringLiteral:
return getTypeFromStringLiteral(<LiteralExpression>node);
case SyntaxKind.TypeReference:
return getTypeFromTypeReferenceNode(<TypeReferenceNode>node);
case SyntaxKind.TypeQuery:
return getTypeFromTypeQueryNode(<TypeQueryNode>node);
case SyntaxKind.ArrayType:
return getTypeFromArrayTypeNode(<ArrayTypeNode>node);
case SyntaxKind.TupleType:
return getTypeFromTupleTypeNode(<TupleTypeNode>node);
case SyntaxKind.UnionType:
return getTypeFromUnionTypeNode(<UnionTypeNode>node);
case SyntaxKind.ParenthesizedType:
return getTypeFromTypeNode((<ParenthesizedTypeNode>node).type);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.TypeLiteral:
return getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node);
// This function assumes that an identifier or qualified name is a type expression
// Callers should first ensure this by calling isTypeNode
case SyntaxKind.Identifier:
case SyntaxKind.QualifiedName:
var symbol = getSymbolInfo(node);
return symbol && getDeclaredTypeOfSymbol(symbol);
default:
return unknownType;
}
}
function instantiateList<T>(items: T[], mapper: TypeMapper, instantiator: (item: T, mapper: TypeMapper) => T): T[] {
if (items && items.length) {
var result: T[] = [];
for (var i = 0; i < items.length; i++) {
result.push(instantiator(items[i], mapper));
}
return result;
}
return items;
}
function createUnaryTypeMapper(source: Type, target: Type): TypeMapper {
return t => t === source ? target : t;
}
function createBinaryTypeMapper(source1: Type, target1: Type, source2: Type, target2: Type): TypeMapper {
return t => t === source1 ? target1 : t === source2 ? target2 : t;
}
function createTypeMapper(sources: Type[], targets: Type[]): TypeMapper {
switch (sources.length) {
case 1: return createUnaryTypeMapper(sources[0], targets[0]);
case 2: return createBinaryTypeMapper(sources[0], targets[0], sources[1], targets[1]);
}
return t => {
for (var i = 0; i < sources.length; i++) {
if (t === sources[i]) return targets[i];
}
return t;
};
}
function createUnaryTypeEraser(source: Type): TypeMapper {
return t => t === source ? anyType : t;
}
function createBinaryTypeEraser(source1: Type, source2: Type): TypeMapper {
return t => t === source1 || t === source2 ? anyType : t;
}
function createTypeEraser(sources: Type[]): TypeMapper {
switch (sources.length) {
case 1: return createUnaryTypeEraser(sources[0]);
case 2: return createBinaryTypeEraser(sources[0], sources[1]);
}
return t => {
for (var i = 0; i < sources.length; i++) {
if (t === sources[i]) return anyType;
}
return t;
};
}
function createInferenceMapper(context: InferenceContext): TypeMapper {
return t => {
for (var i = 0; i < context.typeParameters.length; i++) {
if (t === context.typeParameters[i]) {
return getInferredType(context, i);
}
}
return t;
}
}
function identityMapper(type: Type): Type {
return type;
}
function combineTypeMappers(mapper1: TypeMapper, mapper2: TypeMapper): TypeMapper {
return t => mapper2(mapper1(t));
}
function instantiateTypeParameter(typeParameter: TypeParameter, mapper: TypeMapper): TypeParameter {
var result = <TypeParameter>createType(TypeFlags.TypeParameter);
result.symbol = typeParameter.symbol;
if (typeParameter.constraint) {
result.constraint = instantiateType(typeParameter.constraint, mapper);
}
else {
result.target = typeParameter;
result.mapper = mapper;
}
return result;
}
function instantiateSignature(signature: Signature, mapper: TypeMapper, eraseTypeParameters?: boolean): Signature {
if (signature.typeParameters && !eraseTypeParameters) {
var freshTypeParameters = instantiateList(signature.typeParameters, mapper, instantiateTypeParameter);
mapper = combineTypeMappers(createTypeMapper(signature.typeParameters, freshTypeParameters), mapper);
}
var result = createSignature(signature.declaration, freshTypeParameters,
instantiateList(signature.parameters, mapper, instantiateSymbol),
signature.resolvedReturnType ? instantiateType(signature.resolvedReturnType, mapper) : undefined,
signature.minArgumentCount, signature.hasRestParameter, signature.hasStringLiterals);
result.target = signature;
result.mapper = mapper;
return result;
}
function instantiateSymbol(symbol: Symbol, mapper: TypeMapper): Symbol {
if (symbol.flags & SymbolFlags.Instantiated) {
var links = getSymbolLinks(symbol);
// If symbol being instantiated is itself a instantiation, fetch the original target and combine the
// type mappers. This ensures that original type identities are properly preserved and that aliases
// always reference a non-aliases.
symbol = links.target;
mapper = combineTypeMappers(links.mapper, mapper);
}
// Keep the flags from the symbol we're instantiating. Mark that is instantiated, and
// also transient so that we can just store data on it directly.
var result = <TransientSymbol>createSymbol(SymbolFlags.Instantiated | SymbolFlags.Transient | symbol.flags, symbol.name);
result.declarations = symbol.declarations;
result.parent = symbol.parent;
result.target = symbol;
result.mapper = mapper;
if (symbol.valueDeclaration) {
result.valueDeclaration = symbol.valueDeclaration;
}
return result;
}
function instantiateAnonymousType(type: ObjectType, mapper: TypeMapper): ObjectType {
var result = <ResolvedType>createObjectType(TypeFlags.Anonymous, type.symbol);
result.properties = instantiateList(getPropertiesOfObjectType(type), mapper, instantiateSymbol);
result.members = createSymbolTable(result.properties);
result.callSignatures = instantiateList(getSignaturesOfType(type, SignatureKind.Call), mapper, instantiateSignature);
result.constructSignatures = instantiateList(getSignaturesOfType(type, SignatureKind.Construct), mapper, instantiateSignature);
var stringIndexType = getIndexTypeOfType(type, IndexKind.String);
var numberIndexType = getIndexTypeOfType(type, IndexKind.Number);
if (stringIndexType) result.stringIndexType = instantiateType(stringIndexType, mapper);
if (numberIndexType) result.numberIndexType = instantiateType(numberIndexType, mapper);
return result;
}
function instantiateType(type: Type, mapper: TypeMapper): Type {
if (mapper !== identityMapper) {
if (type.flags & TypeFlags.TypeParameter) {
return mapper(type);
}
if (type.flags & TypeFlags.Anonymous) {
return type.symbol && type.symbol.flags & (SymbolFlags.Function | SymbolFlags.Method | SymbolFlags.TypeLiteral | SymbolFlags.ObjectLiteral) ?
instantiateAnonymousType(<ObjectType>type, mapper) : type;
}
if (type.flags & TypeFlags.Reference) {
return createTypeReference((<TypeReference>type).target, instantiateList((<TypeReference>type).typeArguments, mapper, instantiateType));
}
if (type.flags & TypeFlags.Tuple) {
return createTupleType(instantiateList((<TupleType>type).elementTypes, mapper, instantiateType));
}
if (type.flags & TypeFlags.Union) {
return getUnionType(instantiateList((<UnionType>type).types, mapper, instantiateType), /*noSubtypeReduction*/ true);
}
}
return type;
}
// Returns true if the given expression contains (at any level of nesting) a function or arrow expression
// that is subject to contextual typing.
function isContextSensitiveExpression(node: Expression): boolean {
switch (node.kind) {
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
return !(<FunctionExpression>node).typeParameters && !forEach((<FunctionExpression>node).parameters, p => p.type);
case SyntaxKind.ObjectLiteralExpression:
return forEach((<ObjectLiteralExpression>node).properties, p =>
p.kind === SyntaxKind.PropertyAssignment && isContextSensitiveExpression((<PropertyDeclaration>p).initializer));
case SyntaxKind.ArrayLiteralExpression:
return forEach((<ArrayLiteralExpression>node).elements, e => isContextSensitiveExpression(e));
case SyntaxKind.ConditionalExpression:
return isContextSensitiveExpression((<ConditionalExpression>node).whenTrue) ||
isContextSensitiveExpression((<ConditionalExpression>node).whenFalse);
case SyntaxKind.BinaryExpression:
return (<BinaryExpression>node).operator === SyntaxKind.BarBarToken &&
(isContextSensitiveExpression((<BinaryExpression>node).left) || isContextSensitiveExpression((<BinaryExpression>node).right));
}
return false;
}
function getTypeWithoutConstructors(type: Type): Type {
if (type.flags & TypeFlags.ObjectType) {
var resolved = resolveObjectOrUnionTypeMembers(<ObjectType>type);
if (resolved.constructSignatures.length) {
var result = <ResolvedType>createObjectType(TypeFlags.Anonymous, type.symbol);
result.members = resolved.members;
result.properties = resolved.properties;
result.callSignatures = resolved.callSignatures;
result.constructSignatures = emptyArray;
type = result;
}
}
return type;
}
// TYPE CHECKING
var subtypeRelation: Map<boolean> = {};
var assignableRelation: Map<boolean> = {};
var identityRelation: Map<boolean> = {};
function isTypeIdenticalTo(source: Type, target: Type): boolean {
return checkTypeRelatedTo(source, target, identityRelation, /*errorNode*/ undefined);
}
function compareTypes(source: Type, target: Type): Ternary {
return checkTypeRelatedTo(source, target, identityRelation, /*errorNode*/ undefined) ? Ternary.True : Ternary.False;
}
function isTypeSubtypeOf(source: Type, target: Type): boolean {
return checkTypeSubtypeOf(source, target, /*errorNode*/ undefined);
}
function isTypeAssignableTo(source: Type, target: Type): boolean {
return checkTypeAssignableTo(source, target, /*errorNode*/ undefined);
}
function checkTypeSubtypeOf(source: Type, target: Type, errorNode: Node, headMessage?: DiagnosticMessage, containingMessageChain?: DiagnosticMessageChain): boolean {
return checkTypeRelatedTo(source, target, subtypeRelation, errorNode, headMessage, containingMessageChain);
}
function checkTypeAssignableTo(source: Type, target: Type, errorNode: Node, headMessage?: DiagnosticMessage): boolean {
return checkTypeRelatedTo(source, target, assignableRelation, errorNode, headMessage);
}
function isSignatureAssignableTo(source: Signature, target: Signature): boolean {
var sourceType = getOrCreateTypeFromSignature(source);
var targetType = getOrCreateTypeFromSignature(target);
return checkTypeRelatedTo(sourceType, targetType, assignableRelation, /*errorNode*/ undefined);
}
function checkTypeRelatedTo(
source: Type,
target: Type,
relation: Map<boolean>,
errorNode: Node,
headMessage?: DiagnosticMessage,
containingMessageChain?: DiagnosticMessageChain): boolean {
var errorInfo: DiagnosticMessageChain;
var sourceStack: ObjectType[];
var targetStack: ObjectType[];
var maybeStack: Map<boolean>[];
var expandingFlags: number;
var depth = 0;
var overflow = false;
Debug.assert(relation !== identityRelation || !errorNode, "no error reporting in identity checking");
var result = isRelatedTo(source, target, errorNode !== undefined, headMessage);
if (overflow) {
error(errorNode, Diagnostics.Excessive_stack_depth_comparing_types_0_and_1, typeToString(source), typeToString(target));
}
else if (errorInfo) {
if (containingMessageChain) {
errorInfo = concatenateDiagnosticMessageChains(containingMessageChain, errorInfo);
}
addDiagnostic(createDiagnosticForNodeFromMessageChain(errorNode, errorInfo, program.getCompilerHost().getNewLine()));
}
return result !== Ternary.False;
function reportError(message: DiagnosticMessage, arg0?: string, arg1?: string, arg2?: string): void {
errorInfo = chainDiagnosticMessages(errorInfo, message, arg0, arg1, arg2);
}
// Compare two types and return
// Ternary.True if they are related with no assumptions,
// Ternary.Maybe if they are related with assumptions of other relationships, or
// Ternary.False if they are not related.
function isRelatedTo(source: Type, target: Type, reportErrors?: boolean, headMessage?: DiagnosticMessage): Ternary {
var result: Ternary;
if (relation === identityRelation) {
// both types are the same - covers 'they are the same primitive type or both are Any' or the same type parameter cases
if (source === target) return Ternary.True;
}
else {
if (source === target) return Ternary.True;
if (target.flags & TypeFlags.Any) return Ternary.True;
if (source === undefinedType) return Ternary.True;
if (source === nullType && target !== undefinedType) return Ternary.True;
if (source.flags & TypeFlags.Enum && target === numberType) return Ternary.True;
if (source.flags & TypeFlags.StringLiteral && target === stringType) return Ternary.True;
if (relation === assignableRelation) {
if (source.flags & TypeFlags.Any) return Ternary.True;
if (source === numberType && target.flags & TypeFlags.Enum) return Ternary.True;
}
}
if (source.flags & TypeFlags.Union) {
if (result = unionTypeRelatedToType(<UnionType>source, target, reportErrors)) {
return result;
}
}
else if (target.flags & TypeFlags.Union) {
if (result = typeRelatedToUnionType(source, <UnionType>target, reportErrors)) {
return result;
}
}
else if (source.flags & TypeFlags.TypeParameter && target.flags & TypeFlags.TypeParameter) {
if (result = typeParameterRelatedTo(<TypeParameter>source, <TypeParameter>target, reportErrors)) {
return result;
}
}
else {
var saveErrorInfo = errorInfo;
if (source.flags & TypeFlags.Reference && target.flags & TypeFlags.Reference && (<TypeReference>source).target === (<TypeReference>target).target) {
// We have type references to same target type, see if relationship holds for all type arguments
if (result = typesRelatedTo((<TypeReference>source).typeArguments, (<TypeReference>target).typeArguments, reportErrors)) {
return result;
}
}
// Even if relationship doesn't hold for type arguments, it may hold in a structural comparison
// Report structural errors only if we haven't reported any errors yet
var reportStructuralErrors = reportErrors && errorInfo === saveErrorInfo;
// identity relation does not use apparent type
var sourceOrApparentType = relation === identityRelation ? source : getApparentType(source);
if (sourceOrApparentType.flags & TypeFlags.ObjectType && target.flags & TypeFlags.ObjectType &&
(result = objectTypeRelatedTo(sourceOrApparentType, <ObjectType>target, reportStructuralErrors))) {
errorInfo = saveErrorInfo;
return result;
}
}
if (reportErrors) {
headMessage = headMessage || Diagnostics.Type_0_is_not_assignable_to_type_1;
reportError(headMessage, typeToString(source), typeToString(target));
}
return Ternary.False;
}
function typeRelatedToUnionType(source: Type, target: UnionType, reportErrors: boolean): Ternary {
var targetTypes = target.types;
for (var i = 0, len = targetTypes.length; i < len; i++) {
var related = isRelatedTo(source, targetTypes[i], reportErrors && i === len - 1);
if (related) {
return related;
}
}
return Ternary.False;
}
function unionTypeRelatedToType(source: UnionType, target: Type, reportErrors: boolean): Ternary {
var result = Ternary.True;
var sourceTypes = source.types;
for (var i = 0, len = sourceTypes.length; i < len; i++) {
var related = isRelatedTo(sourceTypes[i], target, reportErrors);
if (!related) {
return Ternary.False;
}
result &= related;
}
return result;
}
function typesRelatedTo(sources: Type[], targets: Type[], reportErrors: boolean): Ternary {
var result = Ternary.True;
for (var i = 0, len = sources.length; i < len; i++) {
var related = isRelatedTo(sources[i], targets[i], reportErrors);
if (!related) {
return Ternary.False;
}
result &= related;
}
return result;
}
function typeParameterRelatedTo(source: TypeParameter, target: TypeParameter, reportErrors: boolean): Ternary {
if (relation === identityRelation) {
if (source.symbol.name !== target.symbol.name) {
return Ternary.False;
}
// covers case when both type parameters does not have constraint (both equal to noConstraintType)
if (source.constraint === target.constraint) {
return Ternary.True;
}
if (source.constraint === noConstraintType || target.constraint === noConstraintType) {
return Ternary.False;
}
return isRelatedTo(source.constraint, target.constraint, reportErrors);
}
else {
while (true) {
var constraint = getConstraintOfTypeParameter(source);
if (constraint === target) return Ternary.True;
if (!(constraint && constraint.flags & TypeFlags.TypeParameter)) break;
source = <TypeParameter>constraint;
}
return Ternary.False;
}
}
// Determine if two object types are related by structure. First, check if the result is already available in the global cache.
// Second, check if we have already started a comparison of the given two types in which case we assume the result to be true.
// Third, check if both types are part of deeply nested chains of generic type instantiations and if so assume the types are
// equal and infinitely expanding. Fourth, if we have reached a depth of 100 nested comparisons, assume we have runaway recursion
// and issue an error. Otherwise, actually compare the structure of the two types.
function objectTypeRelatedTo(source: ObjectType, target: ObjectType, reportErrors: boolean): Ternary {
if (overflow) {
return Ternary.False;
}
var id = source.id + "," + target.id;
var related = relation[id];
if (related !== undefined) {
return related ? Ternary.True : Ternary.False;
}
if (depth > 0) {
for (var i = 0; i < depth; i++) {
// If source and target are already being compared, consider them related with assumptions
if (maybeStack[i][id]) {
return Ternary.Maybe;
}
}
if (depth === 100) {
overflow = true;
return Ternary.False;
}
}
else {
sourceStack = [];
targetStack = [];
maybeStack = [];
expandingFlags = 0;
}
sourceStack[depth] = source;
targetStack[depth] = target;
maybeStack[depth] = {};
maybeStack[depth][id] = true;
depth++;
var saveExpandingFlags = expandingFlags;
if (!(expandingFlags & 1) && isDeeplyNestedGeneric(source, sourceStack)) expandingFlags |= 1;
if (!(expandingFlags & 2) && isDeeplyNestedGeneric(target, targetStack)) expandingFlags |= 2;
if (expandingFlags === 3) {
var result = Ternary.Maybe;
}
else {
var result = propertiesRelatedTo(source, target, reportErrors);
if (result) {
result &= signaturesRelatedTo(source, target, SignatureKind.Call, reportErrors);
if (result) {
result &= signaturesRelatedTo(source, target, SignatureKind.Construct, reportErrors);
if (result) {
result &= stringIndexTypesRelatedTo(source, target, reportErrors);
if (result) {
result &= numberIndexTypesRelatedTo(source, target, reportErrors);
}
}
}
}
}
expandingFlags = saveExpandingFlags;
depth--;
if (result) {
var maybeCache = maybeStack[depth];
// If result is definitely true, copy assumptions to global cache, else copy to next level up
var destinationCache = result === Ternary.True || depth === 0 ? relation : maybeStack[depth - 1];
for (var p in maybeCache) {
destinationCache[p] = maybeCache[p];
}
}
else {
// A false result goes straight into global cache (when something is false under assumptions it
// will also be false without assumptions)
relation[id] = false;
}
return result;
}
// Return true if the given type is part of a deeply nested chain of generic instantiations. We consider this to be the case
// when structural type comparisons have been started for 10 or more instantiations of the same generic type. It is possible,
// though highly unlikely, for this test to be true in a situation where a chain of instantiations is not infinitely expanding.
// Effectively, we will generate a false positive when two types are structurally equal to at least 10 levels, but unequal at
// some level beyond that.
function isDeeplyNestedGeneric(type: ObjectType, stack: ObjectType[]): boolean {
if (type.flags & TypeFlags.Reference && depth >= 10) {
var target = (<TypeReference>type).target;
var count = 0;
for (var i = 0; i < depth; i++) {
var t = stack[i];
if (t.flags & TypeFlags.Reference && (<TypeReference>t).target === target) {
count++;
if (count >= 10) return true;
}
}
}
return false;
}
function propertiesRelatedTo(source: ObjectType, target: ObjectType, reportErrors: boolean): Ternary {
if (relation === identityRelation) {
return propertiesIdenticalTo(source, target);
}
var result = Ternary.True;
var properties = getPropertiesOfObjectType(target);
for (var i = 0; i < properties.length; i++) {
var targetProp = properties[i];
var sourceProp = getPropertyOfType(source, targetProp.name);
if (sourceProp !== targetProp) {
if (!sourceProp) {
if (relation === subtypeRelation || !isOptionalProperty(targetProp)) {
if (reportErrors) {
reportError(Diagnostics.Property_0_is_missing_in_type_1, symbolToString(targetProp), typeToString(source));
}
return Ternary.False;
}
}
else if (!(targetProp.flags & SymbolFlags.Prototype)) {
var sourceFlags = getDeclarationFlagsFromSymbol(sourceProp);
var targetFlags = getDeclarationFlagsFromSymbol(targetProp);
if (sourceFlags & NodeFlags.Private || targetFlags & NodeFlags.Private) {
if (sourceProp.valueDeclaration !== targetProp.valueDeclaration) {
if (reportErrors) {
if (sourceFlags & NodeFlags.Private && targetFlags & NodeFlags.Private) {
reportError(Diagnostics.Types_have_separate_declarations_of_a_private_property_0, symbolToString(targetProp));
}
else {
reportError(Diagnostics.Property_0_is_private_in_type_1_but_not_in_type_2, symbolToString(targetProp),
typeToString(sourceFlags & NodeFlags.Private ? source : target),
typeToString(sourceFlags & NodeFlags.Private ? target : source));
}
}
return Ternary.False;
}
}
else if (targetFlags & NodeFlags.Protected) {
var sourceDeclaredInClass = sourceProp.parent && sourceProp.parent.flags & SymbolFlags.Class;
var sourceClass = sourceDeclaredInClass ? <InterfaceType>getDeclaredTypeOfSymbol(sourceProp.parent) : undefined;
var targetClass = <InterfaceType>getDeclaredTypeOfSymbol(targetProp.parent);
if (!sourceClass || !hasBaseType(sourceClass, targetClass)) {
if (reportErrors) {
reportError(Diagnostics.Property_0_is_protected_but_type_1_is_not_a_class_derived_from_2,
symbolToString(targetProp), typeToString(sourceClass || source), typeToString(targetClass));
}
return Ternary.False;
}
}
else if (sourceFlags & NodeFlags.Protected) {
if (reportErrors) {
reportError(Diagnostics.Property_0_is_protected_in_type_1_but_public_in_type_2,
symbolToString(targetProp), typeToString(source), typeToString(target));
}
return Ternary.False;
}
var related = isRelatedTo(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp), reportErrors);
if (!related) {
if (reportErrors) {
reportError(Diagnostics.Types_of_property_0_are_incompatible, symbolToString(targetProp));
}
return Ternary.False;
}
result &= related;
if (isOptionalProperty(sourceProp) && !isOptionalProperty(targetProp)) {
// TypeScript 1.0 spec (April 2014): 3.8.3
// S is a subtype of a type T, and T is a supertype of S if ...
// S' and T are object types and, for each member M in T..
// M is a property and S' contains a property N where
// if M is a required property, N is also a required property
// (M - property in T)
// (N - property in S)
if (reportErrors) {
reportError(Diagnostics.Property_0_is_optional_in_type_1_but_required_in_type_2,
symbolToString(targetProp), typeToString(source), typeToString(target));
}
return Ternary.False;
}
}
}
}
return result;
}
function propertiesIdenticalTo(source: ObjectType, target: ObjectType): Ternary {
var sourceProperties = getPropertiesOfObjectType(source);
var targetProperties = getPropertiesOfObjectType(target);
if (sourceProperties.length !== targetProperties.length) {
return Ternary.False;
}
var result = Ternary.True;
for (var i = 0, len = sourceProperties.length; i < len; ++i) {
var sourceProp = sourceProperties[i];
var targetProp = getPropertyOfObjectType(target, sourceProp.name);
if (!targetProp) {
return Ternary.False;
}
var related = compareProperties(sourceProp, targetProp, isRelatedTo);
if (!related) {
return Ternary.False;
}
result &= related;
}
return result;
}
function signaturesRelatedTo(source: ObjectType, target: ObjectType, kind: SignatureKind, reportErrors: boolean): Ternary {
if (relation === identityRelation) {
return signaturesIdenticalTo(source, target, kind);
}
if (target === anyFunctionType || source === anyFunctionType) {
return Ternary.True;
}
var sourceSignatures = getSignaturesOfType(source, kind);
var targetSignatures = getSignaturesOfType(target, kind);
var result = Ternary.True;
var saveErrorInfo = errorInfo;
outer: for (var i = 0; i < targetSignatures.length; i++) {
var t = targetSignatures[i];
if (!t.hasStringLiterals || target.flags & TypeFlags.FromSignature) {
var localErrors = reportErrors;
for (var j = 0; j < sourceSignatures.length; j++) {
var s = sourceSignatures[j];
if (!s.hasStringLiterals || source.flags & TypeFlags.FromSignature) {
var related = signatureRelatedTo(s, t, localErrors);
if (related) {
result &= related;
errorInfo = saveErrorInfo;
continue outer;
}
// Only report errors from the first failure
localErrors = false;
}
}
return Ternary.False;
}
}
return result;
}
function signatureRelatedTo(source: Signature, target: Signature, reportErrors: boolean): Ternary {
if (source === target) {
return Ternary.True;
}
if (!target.hasRestParameter && source.minArgumentCount > target.parameters.length) {
return Ternary.False;
}
var sourceMax = source.parameters.length;
var targetMax = target.parameters.length;
var checkCount: number;
if (source.hasRestParameter && target.hasRestParameter) {
checkCount = sourceMax > targetMax ? sourceMax : targetMax;
sourceMax--;
targetMax--;
}
else if (source.hasRestParameter) {
sourceMax--;
checkCount = targetMax;
}
else if (target.hasRestParameter) {
targetMax--;
checkCount = sourceMax;
}
else {
checkCount = sourceMax < targetMax ? sourceMax : targetMax;
}
// Spec 1.0 Section 3.8.3 & 3.8.4:
// M and N (the signatures) are instantiated using type Any as the type argument for all type parameters declared by M and N
source = getErasedSignature(source);
target = getErasedSignature(target);
var result = Ternary.True;
for (var i = 0; i < checkCount; i++) {
var s = i < sourceMax ? getTypeOfSymbol(source.parameters[i]) : getRestTypeOfSignature(source);
var t = i < targetMax ? getTypeOfSymbol(target.parameters[i]) : getRestTypeOfSignature(target);
var saveErrorInfo = errorInfo;
var related = isRelatedTo(s, t, reportErrors);
if (!related) {
related = isRelatedTo(t, s, false);
if (!related) {
if (reportErrors) {
reportError(Diagnostics.Types_of_parameters_0_and_1_are_incompatible,
source.parameters[i < sourceMax ? i : sourceMax].name,
target.parameters[i < targetMax ? i : targetMax].name);
}
return Ternary.False;
}
errorInfo = saveErrorInfo;
}
result &= related;
}
var t = getReturnTypeOfSignature(target);
if (t === voidType) return result;
var s = getReturnTypeOfSignature(source);
return result & isRelatedTo(s, t, reportErrors);
}
function signaturesIdenticalTo(source: ObjectType, target: ObjectType, kind: SignatureKind): Ternary {
var sourceSignatures = getSignaturesOfType(source, kind);
var targetSignatures = getSignaturesOfType(target, kind);
if (sourceSignatures.length !== targetSignatures.length) {
return Ternary.False;
}
var result = Ternary.True;
for (var i = 0, len = sourceSignatures.length; i < len; ++i) {
var related = compareSignatures(sourceSignatures[i], targetSignatures[i], /*compareReturnTypes*/ true, isRelatedTo);
if (!related) {
return Ternary.False;
}
result &= related;
}
return result;
}
function stringIndexTypesRelatedTo(source: ObjectType, target: ObjectType, reportErrors: boolean): Ternary {
if (relation === identityRelation) {
return indexTypesIdenticalTo(IndexKind.String, source, target);
}
var targetType = getIndexTypeOfType(target, IndexKind.String);
if (targetType) {
var sourceType = getIndexTypeOfType(source, IndexKind.String);
if (!sourceType) {
if (reportErrors) {
reportError(Diagnostics.Index_signature_is_missing_in_type_0, typeToString(source));
}
return Ternary.False;
}
var related = isRelatedTo(sourceType, targetType, reportErrors);
if (!related) {
if (reportErrors) {
reportError(Diagnostics.Index_signatures_are_incompatible);
}
return Ternary.False;
}
return related;
}
return Ternary.True;
}
function numberIndexTypesRelatedTo(source: ObjectType, target: ObjectType, reportErrors: boolean): Ternary {
if (relation === identityRelation) {
return indexTypesIdenticalTo(IndexKind.Number, source, target);
}
var targetType = getIndexTypeOfType(target, IndexKind.Number);
if (targetType) {
var sourceStringType = getIndexTypeOfType(source, IndexKind.String);
var sourceNumberType = getIndexTypeOfType(source, IndexKind.Number);
if (!(sourceStringType || sourceNumberType)) {
if (reportErrors) {
reportError(Diagnostics.Index_signature_is_missing_in_type_0, typeToString(source));
}
return Ternary.False;
}
if (sourceStringType && sourceNumberType) {
// If we know for sure we're testing both string and numeric index types then only report errors from the second one
var related = isRelatedTo(sourceStringType, targetType, false) || isRelatedTo(sourceNumberType, targetType, reportErrors);
}
else {
var related = isRelatedTo(sourceStringType || sourceNumberType, targetType, reportErrors);
}
if (!related) {
if (reportErrors) {
reportError(Diagnostics.Index_signatures_are_incompatible);
}
return Ternary.False;
}
return related;
}
return Ternary.True;
}
function indexTypesIdenticalTo(indexKind: IndexKind, source: ObjectType, target: ObjectType): Ternary {
var targetType = getIndexTypeOfType(target, indexKind);
var sourceType = getIndexTypeOfType(source, indexKind);
if (!sourceType && !targetType) {
return Ternary.True;
}
if (sourceType && targetType) {
return isRelatedTo(sourceType, targetType);
}
return Ternary.False;
}
}
function isPropertyIdenticalTo(sourceProp: Symbol, targetProp: Symbol): boolean {
return compareProperties(sourceProp, targetProp, compareTypes) !== Ternary.False;
}
function compareProperties(sourceProp: Symbol, targetProp: Symbol, compareTypes: (source: Type, target: Type) => Ternary): Ternary {
// Two members are considered identical when
// - they are public properties with identical names, optionality, and types,
// - they are private or protected properties originating in the same declaration and having identical types
if (sourceProp === targetProp) {
return Ternary.True;
}
var sourcePropAccessibility = getDeclarationFlagsFromSymbol(sourceProp) & (NodeFlags.Private | NodeFlags.Protected);
var targetPropAccessibility = getDeclarationFlagsFromSymbol(targetProp) & (NodeFlags.Private | NodeFlags.Protected);
if (sourcePropAccessibility !== targetPropAccessibility) {
return Ternary.False;
}
if (sourcePropAccessibility) {
if (getTargetSymbol(sourceProp) !== getTargetSymbol(targetProp)) {
return Ternary.False;
}
}
else {
if (isOptionalProperty(sourceProp) !== isOptionalProperty(targetProp)) {
return Ternary.False;
}
}
return compareTypes(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp));
}
function compareSignatures(source: Signature, target: Signature, compareReturnTypes: boolean, compareTypes: (s: Type, t: Type) => Ternary): Ternary {
if (source === target) {
return Ternary.True;
}
if (source.parameters.length !== target.parameters.length ||
source.minArgumentCount !== target.minArgumentCount ||
source.hasRestParameter !== target.hasRestParameter) {
return Ternary.False;
}
var result = Ternary.True;
if (source.typeParameters && target.typeParameters) {
if (source.typeParameters.length !== target.typeParameters.length) {
return Ternary.False;
}
for (var i = 0, len = source.typeParameters.length; i < len; ++i) {
var related = compareTypes(source.typeParameters[i], target.typeParameters[i]);
if (!related) {
return Ternary.False;
}
result &= related;
}
}
else if (source.typeParameters || source.typeParameters) {
return Ternary.False;
}
// Spec 1.0 Section 3.8.3 & 3.8.4:
// M and N (the signatures) are instantiated using type Any as the type argument for all type parameters declared by M and N
source = getErasedSignature(source);
target = getErasedSignature(target);
for (var i = 0, len = source.parameters.length; i < len; i++) {
var s = source.hasRestParameter && i === len - 1 ? getRestTypeOfSignature(source) : getTypeOfSymbol(source.parameters[i]);
var t = target.hasRestParameter && i === len - 1 ? getRestTypeOfSignature(target) : getTypeOfSymbol(target.parameters[i]);
var related = compareTypes(s, t);
if (!related) {
return Ternary.False;
}
result &= related;
}
if (compareReturnTypes) {
result &= compareTypes(getReturnTypeOfSignature(source), getReturnTypeOfSignature(target));
}
return result;
}
function isSupertypeOfEach(candidate: Type, types: Type[]): boolean {
for (var i = 0, len = types.length; i < len; i++) {
if (candidate !== types[i] && !isTypeSubtypeOf(types[i], candidate)) return false;
}
return true;
}
function getCommonSupertype(types: Type[]): Type {
return forEach(types, t => isSupertypeOfEach(t, types) ? t : undefined);
}
function reportNoCommonSupertypeError(types: Type[], errorLocation: Node, errorMessageChainHead: DiagnosticMessageChain): void {
var bestSupertype: Type;
var bestSupertypeDownfallType: Type; // The type that caused bestSupertype not to be the common supertype
var bestSupertypeScore = 0;
for (var i = 0; i < types.length; i++) {
var score = 0;
var downfallType: Type = undefined;
for (var j = 0; j < types.length; j++) {
if (isTypeSubtypeOf(types[j], types[i])) {
score++;
}
else if (!downfallType) {
downfallType = types[j];
}
}
if (score > bestSupertypeScore) {
bestSupertype = types[i];
bestSupertypeDownfallType = downfallType;
bestSupertypeScore = score;
}
// types.length - 1 is the maximum score, given that getCommonSupertype returned false
if (bestSupertypeScore === types.length - 1) {
break;
}
}
// In the following errors, the {1} slot is before the {0} slot because checkTypeSubtypeOf supplies the
// subtype as the first argument to the error
checkTypeSubtypeOf(bestSupertypeDownfallType, bestSupertype, errorLocation,
Diagnostics.Type_argument_candidate_1_is_not_a_valid_type_argument_because_it_is_not_a_supertype_of_candidate_0,
errorMessageChainHead);
}
function isTypeOfObjectLiteral(type: Type): boolean {
return (type.flags & TypeFlags.Anonymous) && type.symbol && (type.symbol.flags & SymbolFlags.ObjectLiteral) ? true : false;
}
function isArrayType(type: Type): boolean {
return type.flags & TypeFlags.Reference && (<TypeReference>type).target === globalArrayType;
}
function getInnermostTypeOfNestedArrayTypes(type: Type): Type {
while (isArrayType(type)) {
type = (<GenericType>type).typeArguments[0];
}
return type;
}
/* If we are widening on a literal, then we may need to the 'node' parameter for reporting purposes */
function getWidenedType(type: Type, suppressNoImplicitAnyErrors?: boolean): Type {
if (type.flags & (TypeFlags.Undefined | TypeFlags.Null)) {
return anyType;
}
if (type.flags & TypeFlags.Union) {
return getWidenedTypeOfUnion(type);
}
if (isTypeOfObjectLiteral(type)) {
return getWidenedTypeOfObjectLiteral(type);
}
if (isArrayType(type)) {
return getWidenedTypeOfArrayLiteral(type);
}
return type;
function getWidenedTypeOfUnion(type: Type): Type {
return getUnionType(map((<UnionType>type).types, t => getWidenedType(t, suppressNoImplicitAnyErrors)));
}
function getWidenedTypeOfObjectLiteral(type: Type): Type {
var properties = getPropertiesOfObjectType(type);
if (properties.length) {
var widenedTypes: Type[] = [];
var propTypeWasWidened: boolean = false;
forEach(properties, p => {
var propType = getTypeOfSymbol(p);
var widenedType = getWidenedType(propType);
if (propType !== widenedType) {
propTypeWasWidened = true;
if (!suppressNoImplicitAnyErrors && compilerOptions.noImplicitAny && getInnermostTypeOfNestedArrayTypes(widenedType) === anyType) {
error(p.valueDeclaration, Diagnostics.Object_literal_s_property_0_implicitly_has_an_1_type, p.name, typeToString(widenedType));
}
}
widenedTypes.push(widenedType);
});
if (propTypeWasWidened) {
var members: SymbolTable = {};
var index = 0;
forEach(properties, p => {
var symbol = <TransientSymbol>createSymbol(SymbolFlags.Property | SymbolFlags.Transient | p.flags, p.name);
symbol.declarations = p.declarations;
symbol.parent = p.parent;
symbol.type = widenedTypes[index++];
symbol.target = p;
if (p.valueDeclaration) symbol.valueDeclaration = p.valueDeclaration;
members[symbol.name] = symbol;
});
var stringIndexType = getIndexTypeOfType(type, IndexKind.String);
var numberIndexType = getIndexTypeOfType(type, IndexKind.Number);
if (stringIndexType) stringIndexType = getWidenedType(stringIndexType);
if (numberIndexType) numberIndexType = getWidenedType(numberIndexType);
type = createAnonymousType(type.symbol, members, emptyArray, emptyArray, stringIndexType, numberIndexType);
}
}
return type;
}
function getWidenedTypeOfArrayLiteral(type: Type): Type {
var elementType = (<TypeReference>type).typeArguments[0];
var widenedType = getWidenedType(elementType, suppressNoImplicitAnyErrors);
type = elementType !== widenedType ? createArrayType(widenedType) : type;
return type;
}
}
function forEachMatchingParameterType(source: Signature, target: Signature, callback: (s: Type, t: Type) => void) {
var sourceMax = source.parameters.length;
var targetMax = target.parameters.length;
var count: number;
if (source.hasRestParameter && target.hasRestParameter) {
count = sourceMax > targetMax ? sourceMax : targetMax;
sourceMax--;
targetMax--;
}
else if (source.hasRestParameter) {
sourceMax--;
count = targetMax;
}
else if (target.hasRestParameter) {
targetMax--;
count = sourceMax;
}
else {
count = sourceMax < targetMax ? sourceMax : targetMax;
}
for (var i = 0; i < count; i++) {
var s = i < sourceMax ? getTypeOfSymbol(source.parameters[i]) : getRestTypeOfSignature(source);
var t = i < targetMax ? getTypeOfSymbol(target.parameters[i]) : getRestTypeOfSignature(target);
callback(s, t);
}
}
function createInferenceContext(typeParameters: TypeParameter[], inferUnionTypes: boolean): InferenceContext {
var inferences: TypeInferences[] = [];
for (var i = 0; i < typeParameters.length; i++) {
inferences.push({ primary: undefined, secondary: undefined });
}
return {
typeParameters: typeParameters,
inferUnionTypes: inferUnionTypes,
inferenceCount: 0,
inferences: inferences,
inferredTypes: new Array(typeParameters.length),
};
}
function inferTypes(context: InferenceContext, source: Type, target: Type) {
var sourceStack: Type[];
var targetStack: Type[];
var depth = 0;
var inferiority = 0;
inferFromTypes(source, target);
function isInProcess(source: Type, target: Type) {
for (var i = 0; i < depth; i++) {
if (source === sourceStack[i] && target === targetStack[i]) return true;
}
return false;
}
function isWithinDepthLimit(type: Type, stack: Type[]) {
if (depth >= 5) {
var target = (<TypeReference>type).target;
var count = 0;
for (var i = 0; i < depth; i++) {
var t = stack[i];
if (t.flags & TypeFlags.Reference && (<TypeReference>t).target === target) count++;
}
return count < 5;
}
return true;
}
function inferFromTypes(source: Type, target: Type) {
if (target.flags & TypeFlags.TypeParameter) {
// If target is a type parameter, make an inference
var typeParameters = context.typeParameters;
for (var i = 0; i < typeParameters.length; i++) {
if (target === typeParameters[i]) {
var inferences = context.inferences[i];
var candidates = inferiority ?
inferences.secondary || (inferences.secondary = []) :
inferences.primary || (inferences.primary = []);
if (!contains(candidates, source)) candidates.push(source);
break;
}
}
}
else if (source.flags & TypeFlags.Reference && target.flags & TypeFlags.Reference && (<TypeReference>source).target === (<TypeReference>target).target) {
// If source and target are references to the same generic type, infer from type arguments
var sourceTypes = (<TypeReference>source).typeArguments;
var targetTypes = (<TypeReference>target).typeArguments;
for (var i = 0; i < sourceTypes.length; i++) {
inferFromTypes(sourceTypes[i], targetTypes[i]);
}
}
else if (target.flags & TypeFlags.Union) {
var targetTypes = (<UnionType>target).types;
var typeParameterCount = 0;
var typeParameter: TypeParameter;
// First infer to each type in union that isn't a type parameter
for (var i = 0; i < targetTypes.length; i++) {
var t = targetTypes[i];
if (t.flags & TypeFlags.TypeParameter && contains(context.typeParameters, t)) {
typeParameter = <TypeParameter>t;
typeParameterCount++;
}
else {
inferFromTypes(source, t);
}
}
// If union contains a single naked type parameter, make a secondary inference to that type parameter
if (typeParameterCount === 1) {
inferiority++;
inferFromTypes(source, typeParameter);
inferiority--;
}
}
else if (source.flags & TypeFlags.Union) {
// Source is a union type, infer from each consituent type
var sourceTypes = (<UnionType>source).types;
for (var i = 0; i < sourceTypes.length; i++) {
inferFromTypes(sourceTypes[i], target);
}
}
else if (source.flags & TypeFlags.ObjectType && (target.flags & (TypeFlags.Reference | TypeFlags.Tuple) ||
(target.flags & TypeFlags.Anonymous) && target.symbol && target.symbol.flags & (SymbolFlags.Method | SymbolFlags.TypeLiteral))) {
// If source is an object type, and target is a type reference, a tuple type, the type of a method, or a type literal, infer from members
if (!isInProcess(source, target) && isWithinDepthLimit(source, sourceStack) && isWithinDepthLimit(target, targetStack)) {
if (depth === 0) {
sourceStack = [];
targetStack = [];
}
sourceStack[depth] = source;
targetStack[depth] = target;
depth++;
inferFromProperties(source, target);
inferFromSignatures(source, target, SignatureKind.Call);
inferFromSignatures(source, target, SignatureKind.Construct);
inferFromIndexTypes(source, target, IndexKind.String, IndexKind.String);
inferFromIndexTypes(source, target, IndexKind.Number, IndexKind.Number);
inferFromIndexTypes(source, target, IndexKind.String, IndexKind.Number);
depth--;
}
}
}
function inferFromProperties(source: Type, target: Type) {
var properties = getPropertiesOfObjectType(target);
for (var i = 0; i < properties.length; i++) {
var targetProp = properties[i];
var sourceProp = getPropertyOfObjectType(source, targetProp.name);
if (sourceProp) {
inferFromTypes(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp));
}
}
}
function inferFromSignatures(source: Type, target: Type, kind: SignatureKind) {
var sourceSignatures = getSignaturesOfType(source, kind);
var targetSignatures = getSignaturesOfType(target, kind);
var sourceLen = sourceSignatures.length;
var targetLen = targetSignatures.length;
var len = sourceLen < targetLen ? sourceLen : targetLen;
for (var i = 0; i < len; i++) {
inferFromSignature(getErasedSignature(sourceSignatures[sourceLen - len + i]), getErasedSignature(targetSignatures[targetLen - len + i]));
}
}
function inferFromSignature(source: Signature, target: Signature) {
forEachMatchingParameterType(source, target, inferFromTypes);
inferFromTypes(getReturnTypeOfSignature(source), getReturnTypeOfSignature(target));
}
function inferFromIndexTypes(source: Type, target: Type, sourceKind: IndexKind, targetKind: IndexKind) {
var targetIndexType = getIndexTypeOfType(target, targetKind);
if (targetIndexType) {
var sourceIndexType = getIndexTypeOfType(source, sourceKind);
if (sourceIndexType) {
inferFromTypes(sourceIndexType, targetIndexType);
}
}
}
}
function getInferenceCandidates(context: InferenceContext, index: number): Type[]{
var inferences = context.inferences[index];
return inferences.primary || inferences.secondary || emptyArray;
}
function getInferredType(context: InferenceContext, index: number): Type {
var inferredType = context.inferredTypes[index];
if (!inferredType) {
var inferences = getInferenceCandidates(context, index);
if (inferences.length) {
// Infer widened union or supertype, or the undefined type for no common supertype
var unionOrSuperType = context.inferUnionTypes ? getUnionType(inferences) : getCommonSupertype(inferences);
inferredType = unionOrSuperType ? getWidenedType(unionOrSuperType) : inferenceFailureType;
}
else {
// Infer the empty object type when no inferences were made
inferredType = emptyObjectType;
}
if (inferredType !== inferenceFailureType) {
var constraint = getConstraintOfTypeParameter(context.typeParameters[index]);
inferredType = constraint && !isTypeAssignableTo(inferredType, constraint) ? constraint : inferredType;
}
context.inferredTypes[index] = inferredType;
}
return inferredType;
}
function getInferredTypes(context: InferenceContext): Type[] {
for (var i = 0; i < context.inferredTypes.length; i++) {
getInferredType(context, i);
}
return context.inferredTypes;
}
function hasAncestor(node: Node, kind: SyntaxKind): boolean {
return getAncestor(node, kind) !== undefined;
}
// EXPRESSION TYPE CHECKING
function getResolvedSymbol(node: Identifier): Symbol {
var links = getNodeLinks(node);
if (!links.resolvedSymbol) {
links.resolvedSymbol = (getFullWidth(node) > 0 && resolveName(node, node.text, SymbolFlags.Value | SymbolFlags.ExportValue, Diagnostics.Cannot_find_name_0, node)) || unknownSymbol;
}
return links.resolvedSymbol;
}
function isInTypeQuery(node: Node): boolean {
// TypeScript 1.0 spec (April 2014): 3.6.3
// A type query consists of the keyword typeof followed by an expression.
// The expression is restricted to a single identifier or a sequence of identifiers separated by periods
while (node) {
switch (node.kind) {
case SyntaxKind.TypeQuery:
return true;
case SyntaxKind.Identifier:
case SyntaxKind.QualifiedName:
node = node.parent;
continue;
default:
return false;
}
}
Debug.fail("should not get here");
}
// Remove one or more primitive types from a union type
function subtractPrimitiveTypes(type: Type, subtractMask: TypeFlags): Type {
if (type.flags & TypeFlags.Union) {
var types = (<UnionType>type).types;
if (forEach(types, t => t.flags & subtractMask)) {
return getUnionType(filter(types, t => !(t.flags & subtractMask)));
}
}
return type;
}
// Check if a given variable is assigned within a given syntax node
function isVariableAssignedWithin(symbol: Symbol, node: Node): boolean {
var links = getNodeLinks(node);
if (links.assignmentChecks) {
var cachedResult = links.assignmentChecks[symbol.id];
if (cachedResult !== undefined) {
return cachedResult;
}
}
else {
links.assignmentChecks = {};
}
return links.assignmentChecks[symbol.id] = isAssignedIn(node);
function isAssignedInBinaryExpression(node: BinaryExpression) {
if (node.operator >= SyntaxKind.FirstAssignment && node.operator <= SyntaxKind.LastAssignment) {
var n = node.left;
while (n.kind === SyntaxKind.ParenthesizedExpression) {
n = (<ParenthesizedExpression>n).expression;
}
if (n.kind === SyntaxKind.Identifier && getResolvedSymbol(<Identifier>n) === symbol) {
return true;
}
}
return forEachChild(node, isAssignedIn);
}
function isAssignedInVariableDeclaration(node: VariableDeclaration) {
if (getSymbolOfNode(node) === symbol && node.initializer) {
return true;
}
return forEachChild(node, isAssignedIn);
}
function isAssignedIn(node: Node): boolean {
switch (node.kind) {
case SyntaxKind.BinaryExpression:
return isAssignedInBinaryExpression(<BinaryExpression>node);
case SyntaxKind.VariableDeclaration:
return isAssignedInVariableDeclaration(<VariableDeclaration>node);
case SyntaxKind.ArrayLiteralExpression:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.PropertyAccessExpression:
case SyntaxKind.ElementAccessExpression:
case SyntaxKind.CallExpression:
case SyntaxKind.NewExpression:
case SyntaxKind.TypeAssertionExpression:
case SyntaxKind.ParenthesizedExpression:
case SyntaxKind.PrefixUnaryExpression:
case SyntaxKind.DeleteExpression:
case SyntaxKind.TypeOfExpression:
case SyntaxKind.VoidExpression:
case SyntaxKind.PostfixUnaryExpression:
case SyntaxKind.ConditionalExpression:
case SyntaxKind.Block:
case SyntaxKind.VariableStatement:
case SyntaxKind.ExpressionStatement:
case SyntaxKind.IfStatement:
case SyntaxKind.DoStatement:
case SyntaxKind.WhileStatement:
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
case SyntaxKind.ReturnStatement:
case SyntaxKind.WithStatement:
case SyntaxKind.SwitchStatement:
case SyntaxKind.CaseClause:
case SyntaxKind.DefaultClause:
case SyntaxKind.LabeledStatement:
case SyntaxKind.ThrowStatement:
case SyntaxKind.TryStatement:
case SyntaxKind.TryBlock:
case SyntaxKind.CatchBlock:
case SyntaxKind.FinallyBlock:
return forEachChild(node, isAssignedIn);
}
return false;
}
}
// Get the narrowed type of a given symbol at a given location
function getNarrowedTypeOfSymbol(symbol: Symbol, node: Node) {
var type = getTypeOfSymbol(symbol);
// Only narrow when symbol is variable of a structured type
if (node && (symbol.flags & SymbolFlags.Variable && type.flags & TypeFlags.Structured)) {
loop: while (node.parent) {
var child = node;
node = node.parent;
var narrowedType = type;
switch (node.kind) {
case SyntaxKind.IfStatement:
// In a branch of an if statement, narrow based on controlling expression
if (child !== (<IfStatement>node).expression) {
narrowedType = narrowType(type, (<IfStatement>node).expression, /*assumeTrue*/ child === (<IfStatement>node).thenStatement);
}
break;
case SyntaxKind.ConditionalExpression:
// In a branch of a conditional expression, narrow based on controlling condition
if (child !== (<ConditionalExpression>node).condition) {
narrowedType = narrowType(type, (<ConditionalExpression>node).condition, /*assumeTrue*/ child === (<ConditionalExpression>node).whenTrue);
}
break;
case SyntaxKind.BinaryExpression:
// In the right operand of an && or ||, narrow based on left operand
if (child === (<BinaryExpression>node).right) {
if ((<BinaryExpression>node).operator === SyntaxKind.AmpersandAmpersandToken) {
narrowedType = narrowType(type, (<BinaryExpression>node).left, /*assumeTrue*/ true);
}
else if ((<BinaryExpression>node).operator === SyntaxKind.BarBarToken) {
narrowedType = narrowType(type, (<BinaryExpression>node).left, /*assumeTrue*/ false);
}
}
break;
case SyntaxKind.SourceFile:
case SyntaxKind.ModuleDeclaration:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.Method:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.Constructor:
// Stop at the first containing function or module declaration
break loop;
}
// Use narrowed type if it is a subtype and construct contains no assignments to variable
if (narrowedType !== type && isTypeSubtypeOf(narrowedType, type)) {
if (isVariableAssignedWithin(symbol, node)) {
break;
}
type = narrowedType;
}
}
}
return type;
function narrowTypeByEquality(type: Type, expr: BinaryExpression, assumeTrue: boolean): Type {
// Check that we have 'typeof <symbol>' on the left and string literal on the right
if (expr.left.kind !== SyntaxKind.TypeOfExpression || expr.right.kind !== SyntaxKind.StringLiteral) {
return type;
}
var left = <TypeOfExpression>expr.left;
var right = <LiteralExpression>expr.right;
if (left.expression.kind !== SyntaxKind.Identifier ||
getResolvedSymbol(<Identifier>left.expression) !== symbol) {
return type;
}
var t = right.text;
var checkType: Type = t === "string" ? stringType : t === "number" ? numberType : t === "boolean" ? booleanType : emptyObjectType;
if (expr.operator === SyntaxKind.ExclamationEqualsEqualsToken) {
assumeTrue = !assumeTrue;
}
if (assumeTrue) {
// The assumed result is true. If check was for a primitive type, that type is the narrowed type. Otherwise we can
// remove the primitive types from the narrowed type.
return checkType === emptyObjectType ? subtractPrimitiveTypes(type, TypeFlags.String | TypeFlags.Number | TypeFlags.Boolean) : checkType;
}
else {
// The assumed result is false. If check was for a primitive type we can remove that type from the narrowed type.
// Otherwise we don't have enough information to do anything.
return checkType === emptyObjectType ? type : subtractPrimitiveTypes(type, checkType.flags);
}
}
function narrowTypeByAnd(type: Type, expr: BinaryExpression, assumeTrue: boolean): Type {
if (assumeTrue) {
// The assumed result is true, therefore we narrow assuming each operand to be true.
return narrowType(narrowType(type, expr.left, /*assumeTrue*/ true), expr.right, /*assumeTrue*/ true);
}
else {
// The assumed result is false. This means either the first operand was false, or the first operand was true
// and the second operand was false. We narrow with those assumptions and union the two resulting types.
return getUnionType([
narrowType(type, expr.left, /*assumeTrue*/ false),
narrowType(narrowType(type, expr.left, /*assumeTrue*/ true), expr.right, /*assumeTrue*/ false)
]);
}
}
function narrowTypeByOr(type: Type, expr: BinaryExpression, assumeTrue: boolean): Type {
if (assumeTrue) {
// The assumed result is true. This means either the first operand was true, or the first operand was false
// and the second operand was true. We narrow with those assumptions and union the two resulting types.
return getUnionType([
narrowType(type, expr.left, /*assumeTrue*/ true),
narrowType(narrowType(type, expr.left, /*assumeTrue*/ false), expr.right, /*assumeTrue*/ true)
]);
}
else {
// The assumed result is false, therefore we narrow assuming each operand to be false.
return narrowType(narrowType(type, expr.left, /*assumeTrue*/ false), expr.right, /*assumeTrue*/ false);
}
}
function narrowTypeByInstanceof(type: Type, expr: BinaryExpression, assumeTrue: boolean): Type {
// Check that assumed result is true and we have variable symbol on the left
if (!assumeTrue || expr.left.kind !== SyntaxKind.Identifier || getResolvedSymbol(<Identifier>expr.left) !== symbol) {
return type;
}
// Check that right operand is a function type with a prototype property
var rightType = checkExpression(expr.right);
if (!isTypeSubtypeOf(rightType, globalFunctionType)) {
return type;
}
var prototypeProperty = getPropertyOfType(rightType, "prototype");
if (!prototypeProperty) {
return type;
}
var prototypeType = getTypeOfSymbol(prototypeProperty);
// Narrow to type of prototype property if it is a subtype of current type
return isTypeSubtypeOf(prototypeType, type) ? prototypeType : type;
}
// Narrow the given type based on the given expression having the assumed boolean value
function narrowType(type: Type, expr: Expression, assumeTrue: boolean): Type {
switch (expr.kind) {
case SyntaxKind.ParenthesizedExpression:
return narrowType(type, (<ParenthesizedExpression>expr).expression, assumeTrue);
case SyntaxKind.BinaryExpression:
var operator = (<BinaryExpression>expr).operator;
if (operator === SyntaxKind.EqualsEqualsEqualsToken || operator === SyntaxKind.ExclamationEqualsEqualsToken) {
return narrowTypeByEquality(type, <BinaryExpression>expr, assumeTrue);
}
else if (operator === SyntaxKind.AmpersandAmpersandToken) {
return narrowTypeByAnd(type, <BinaryExpression>expr, assumeTrue);
}
else if (operator === SyntaxKind.BarBarToken) {
return narrowTypeByOr(type, <BinaryExpression>expr, assumeTrue);
}
else if (operator === SyntaxKind.InstanceOfKeyword) {
return narrowTypeByInstanceof(type, <BinaryExpression>expr, assumeTrue);
}
break;
case SyntaxKind.PrefixUnaryExpression:
if ((<PrefixUnaryExpression>expr).operator === SyntaxKind.ExclamationToken) {
return narrowType(type,(<PrefixUnaryExpression>expr).operand, !assumeTrue);
}
break;
}
return type;
}
}
function checkIdentifier(node: Identifier): Type {
var symbol = getResolvedSymbol(node);
if (symbol.flags & SymbolFlags.Import) {
// Mark the import as referenced so that we emit it in the final .js file.
// exception: identifiers that appear in type queries, const enums, modules that contain only const enums
getSymbolLinks(symbol).referenced = getSymbolLinks(symbol).referenced || (!isInTypeQuery(node) && !isConstEnumOrConstEnumOnlyModule(resolveImport(symbol)));
}
checkCollisionWithCapturedSuperVariable(node, node);
checkCollisionWithCapturedThisVariable(node, node);
checkCollisionWithIndexVariableInGeneratedCode(node, node);
return getNarrowedTypeOfSymbol(getExportSymbolOfValueSymbolIfExported(symbol), node);
}
function captureLexicalThis(node: Node, container: Node): void {
var classNode = container.parent && container.parent.kind === SyntaxKind.ClassDeclaration ? container.parent : undefined;
getNodeLinks(node).flags |= NodeCheckFlags.LexicalThis;
if (container.kind === SyntaxKind.Property || container.kind === SyntaxKind.Constructor) {
getNodeLinks(classNode).flags |= NodeCheckFlags.CaptureThis;
}
else {
getNodeLinks(container).flags |= NodeCheckFlags.CaptureThis;
}
}
function checkThisExpression(node: Node): Type {
// Stop at the first arrow function so that we can
// tell whether 'this' needs to be captured.
var container = getThisContainer(node, /* includeArrowFunctions */ true);
var needToCaptureLexicalThis = false;
// Now skip arrow functions to get the "real" owner of 'this'.
if (container.kind === SyntaxKind.ArrowFunction) {
container = getThisContainer(container, /* includeArrowFunctions */ false);
needToCaptureLexicalThis = true;
}
switch (container.kind) {
case SyntaxKind.ModuleDeclaration:
error(node, Diagnostics.this_cannot_be_referenced_in_a_module_body);
// do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
break;
case SyntaxKind.EnumDeclaration:
error(node, Diagnostics.this_cannot_be_referenced_in_current_location);
// do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
break;
case SyntaxKind.Constructor:
if (isInConstructorArgumentInitializer(node, container)) {
error(node, Diagnostics.this_cannot_be_referenced_in_constructor_arguments);
// do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
}
break;
case SyntaxKind.Property:
if (container.flags & NodeFlags.Static) {
error(node, Diagnostics.this_cannot_be_referenced_in_a_static_property_initializer);
// do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
}
break;
}
if (needToCaptureLexicalThis) {
captureLexicalThis(node, container);
}
var classNode = container.parent && container.parent.kind === SyntaxKind.ClassDeclaration ? container.parent : undefined;
if (classNode) {
var symbol = getSymbolOfNode(classNode);
return container.flags & NodeFlags.Static ? getTypeOfSymbol(symbol) : getDeclaredTypeOfSymbol(symbol);
}
return anyType;
}
function getSuperContainer(node: Node): Node {
while (true) {
node = node.parent;
if (!node) return node;
switch (node.kind) {
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.Property:
case SyntaxKind.Method:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
return node;
}
}
}
function isInConstructorArgumentInitializer(node: Node, constructorDecl: Node): boolean {
for (var n = node; n && n !== constructorDecl; n = n.parent) {
if (n.kind === SyntaxKind.Parameter) {
return true;
}
}
return false;
}
function checkSuperExpression(node: Node): Type {
var isCallExpression = node.parent.kind === SyntaxKind.CallExpression && (<CallExpression>node.parent).expression === node;
var enclosingClass = <ClassDeclaration>getAncestor(node, SyntaxKind.ClassDeclaration);
var baseClass: Type;
if (enclosingClass && getClassBaseTypeNode(enclosingClass)) {
var classType = <InterfaceType>getDeclaredTypeOfSymbol(getSymbolOfNode(enclosingClass));
baseClass = classType.baseTypes.length && classType.baseTypes[0];
}
if (!baseClass) {
error(node, Diagnostics.super_can_only_be_referenced_in_a_derived_class);
return unknownType;
}
var container = getSuperContainer(node);
if (container) {
var canUseSuperExpression = false;
if (isCallExpression) {
// TS 1.0 SPEC (April 2014): 4.8.1
// Super calls are only permitted in constructors of derived classes
canUseSuperExpression = container.kind === SyntaxKind.Constructor;
}
else {
// TS 1.0 SPEC (April 2014)
// 'super' property access is allowed
// - In a constructor, instance member function, instance member accessor, or instance member variable initializer where this references a derived class instance
// - In a static member function or static member accessor
// super property access might appear in arrow functions with arbitrary deep nesting
var needToCaptureLexicalThis = false;
while (container && container.kind === SyntaxKind.ArrowFunction) {
container = getSuperContainer(container);
needToCaptureLexicalThis = true;
}
// topmost container must be something that is directly nested in the class declaration
if (container && container.parent && container.parent.kind === SyntaxKind.ClassDeclaration) {
if (container.flags & NodeFlags.Static) {
canUseSuperExpression =
container.kind === SyntaxKind.Method ||
container.kind === SyntaxKind.GetAccessor ||
container.kind === SyntaxKind.SetAccessor;
}
else {
canUseSuperExpression =
container.kind === SyntaxKind.Method ||
container.kind === SyntaxKind.GetAccessor ||
container.kind === SyntaxKind.SetAccessor ||
container.kind === SyntaxKind.Property ||
container.kind === SyntaxKind.Constructor;
}
}
}
if (canUseSuperExpression) {
var returnType: Type;
if ((container.flags & NodeFlags.Static) || isCallExpression) {
getNodeLinks(node).flags |= NodeCheckFlags.SuperStatic;
returnType = getTypeOfSymbol(baseClass.symbol);
}
else {
getNodeLinks(node).flags |= NodeCheckFlags.SuperInstance;
returnType = baseClass;
}
if (container.kind === SyntaxKind.Constructor && isInConstructorArgumentInitializer(node, container)) {
// issue custom error message for super property access in constructor arguments (to be aligned with old compiler)
error(node, Diagnostics.super_cannot_be_referenced_in_constructor_arguments);
returnType = unknownType;
}
if (!isCallExpression && needToCaptureLexicalThis) {
// call expressions are allowed only in constructors so they should always capture correct 'this'
// super property access expressions can also appear in arrow functions -
// in this case they should also use correct lexical this
captureLexicalThis(node.parent, container);
}
return returnType;
}
}
if (isCallExpression) {
error(node, Diagnostics.Super_calls_are_not_permitted_outside_constructors_or_in_nested_functions_inside_constructors);
}
else {
error(node, Diagnostics.super_property_access_is_permitted_only_in_a_constructor_member_function_or_member_accessor_of_a_derived_class);
}
return unknownType;
}
// Return contextual type of parameter or undefined if no contextual type is available
function getContextuallyTypedParameterType(parameter: ParameterDeclaration): Type {
if (isFunctionExpressionOrArrowFunction(parameter.parent)) {
var func = <FunctionExpression>parameter.parent;
if (isContextSensitiveExpression(func)) {
var contextualSignature = getContextualSignature(func);
if (contextualSignature) {
var funcHasRestParameters = hasRestParameters(func);
var len = func.parameters.length - (funcHasRestParameters ? 1 : 0);
var indexOfParameter = indexOf(func.parameters, parameter);
if (indexOfParameter < len) {
return getTypeAtPosition(contextualSignature, indexOfParameter);
}
// If last parameter is contextually rest parameter get its type
if (indexOfParameter === (func.parameters.length - 1) &&
funcHasRestParameters && contextualSignature.hasRestParameter && func.parameters.length >= contextualSignature.parameters.length) {
return getTypeOfSymbol(contextualSignature.parameters[contextualSignature.parameters.length - 1]);
}
}
}
}
return undefined;
}
// In a variable, parameter or property declaration with a type annotation, the contextual type of an initializer
// expression is the type of the variable, parameter or property. In a parameter declaration of a contextually
// typed function expression, the contextual type of an initializer expression is the contextual type of the
// parameter.
function getContextualTypeForInitializerExpression(node: Expression): Type {
var declaration = <VariableOrParameterDeclaration>node.parent;
if (node === declaration.initializer) {
if (declaration.type) {
return getTypeFromTypeNode(declaration.type);
}
if (declaration.kind === SyntaxKind.Parameter) {
return getContextuallyTypedParameterType(<ParameterDeclaration>declaration);
}
}
return undefined;
}
function getContextualTypeForReturnExpression(node: Expression): Type {
var func = getContainingFunction(node);
if (func) {
// If the containing function has a return type annotation, is a constructor, or is a get accessor whose
// corresponding set accessor has a type annotation, return statements in the function are contextually typed
if (func.type || func.kind === SyntaxKind.Constructor || func.kind === SyntaxKind.GetAccessor && getSetAccessorTypeAnnotationNode(<AccessorDeclaration>getDeclarationOfKind(func.symbol, SyntaxKind.SetAccessor))) {
return getReturnTypeOfSignature(getSignatureFromDeclaration(func));
}
// Otherwise, if the containing function is contextually typed by a function type with exactly one call signature
// and that call signature is non-generic, return statements are contextually typed by the return type of the signature
var signature = getContextualSignatureForFunctionLikeDeclaration(<FunctionExpression>func);
if (signature) {
return getReturnTypeOfSignature(signature);
}
}
return undefined;
}
// In a typed function call, an argument expression is contextually typed by the type of the corresponding parameter.
function getContextualTypeForArgument(node: Expression): Type {
var callExpression = <CallExpression>node.parent;
var argIndex = indexOf(callExpression.arguments, node);
if (argIndex >= 0) {
var signature = getResolvedSignature(callExpression);
return getTypeAtPosition(signature, argIndex);
}
return undefined;
}
function getContextualTypeForBinaryOperand(node: Expression): Type {
var binaryExpression = <BinaryExpression>node.parent;
var operator = binaryExpression.operator;
if (operator >= SyntaxKind.FirstAssignment && operator <= SyntaxKind.LastAssignment) {
// In an assignment expression, the right operand is contextually typed by the type of the left operand.
if (node === binaryExpression.right) {
return checkExpression(binaryExpression.left);
}
}
else if (operator === SyntaxKind.BarBarToken) {
// When an || expression has a contextual type, the operands are contextually typed by that type. When an ||
// expression has no contextual type, the right operand is contextually typed by the type of the left operand.
var type = getContextualType(binaryExpression);
if (!type && node === binaryExpression.right) {
type = checkExpression(binaryExpression.left);
}
return type;
}
return undefined;
}
// Apply a mapping function to a contextual type and return the resulting type. If the contextual type
// is a union type, the mapping function is applied to each constituent type and a union of the resulting
// types is returned.
function applyToContextualType(type: Type, mapper: (t: Type) => Type): Type {
if (!(type.flags & TypeFlags.Union)) {
return mapper(type);
}
var types = (<UnionType>type).types;
var mappedType: Type;
var mappedTypes: Type[];
for (var i = 0; i < types.length; i++) {
var t = mapper(types[i]);
if (t) {
if (!mappedType) {
mappedType = t;
}
else if (!mappedTypes) {
mappedTypes = [mappedType, t];
}
else {
mappedTypes.push(t);
}
}
}
return mappedTypes ? getUnionType(mappedTypes) : mappedType;
}
function getTypeOfPropertyOfContextualType(type: Type, name: string) {
return applyToContextualType(type, t => {
var prop = getPropertyOfObjectType(t, name);
return prop ? getTypeOfSymbol(prop) : undefined;
});
}
function getIndexTypeOfContextualType(type: Type, kind: IndexKind) {
return applyToContextualType(type, t => getIndexTypeOfObjectOrUnionType(t, kind));
}
// Return true if the given contextual type is a tuple-like type
function contextualTypeIsTupleType(type: Type): boolean {
return !!(type.flags & TypeFlags.Union ? forEach((<UnionType>type).types, t => getPropertyOfObjectType(t, "0")) : getPropertyOfObjectType(type, "0"));
}
// Return true if the given contextual type provides an index signature of the given kind
function contextualTypeHasIndexSignature(type: Type, kind: IndexKind): boolean {
return !!(type.flags & TypeFlags.Union ? forEach((<UnionType>type).types, t => getIndexTypeOfObjectOrUnionType(t, kind)) : getIndexTypeOfObjectOrUnionType(type, kind));
}
// In an object literal contextually typed by a type T, the contextual type of a property assignment is the type of
// the matching property in T, if one exists. Otherwise, it is the type of the numeric index signature in T, if one
// exists. Otherwise, it is the type of the string index signature in T, if one exists.
function getContextualTypeForPropertyExpression(node: Expression): Type {
var declaration = <PropertyDeclaration>node.parent;
var objectLiteral = <ObjectLiteralExpression>declaration.parent;
var type = getContextualType(objectLiteral);
// TODO(jfreeman): Handle this case for computed names and symbols
var name = (<Identifier>declaration.name).text;
if (type && name) {
return getTypeOfPropertyOfContextualType(type, name) ||
isNumericName(name) && getIndexTypeOfContextualType(type, IndexKind.Number) ||
getIndexTypeOfContextualType(type, IndexKind.String);
}
return undefined;
}
// In an array literal contextually typed by a type T, the contextual type of an element expression at index N is
// the type of the property with the numeric name N in T, if one exists. Otherwise, it is the type of the numeric
// index signature in T, if one exists.
function getContextualTypeForElementExpression(node: Expression): Type {
var arrayLiteral = <ArrayLiteralExpression>node.parent;
var type = getContextualType(arrayLiteral);
if (type) {
var index = indexOf(arrayLiteral.elements, node);
return getTypeOfPropertyOfContextualType(type, "" + index) || getIndexTypeOfContextualType(type, IndexKind.Number);
}
return undefined;
}
// In a contextually typed conditional expression, the true/false expressions are contextually typed by the same type.
function getContextualTypeForConditionalOperand(node: Expression): Type {
var conditional = <ConditionalExpression>node.parent;
return node === conditional.whenTrue || node === conditional.whenFalse ? getContextualType(conditional) : undefined;
}
// Return the contextual type for a given expression node. During overload resolution, a contextual type may temporarily
// be "pushed" onto a node using the contextualType property.
function getContextualType(node: Expression): Type {
if (isInsideWithStatementBody(node)) {
// We cannot answer semantic questions within a with block, do not proceed any further
return undefined;
}
if (node.contextualType) {
return node.contextualType;
}
var parent = node.parent;
switch (parent.kind) {
case SyntaxKind.VariableDeclaration:
case SyntaxKind.Parameter:
case SyntaxKind.Property:
return getContextualTypeForInitializerExpression(node);
case SyntaxKind.ArrowFunction:
case SyntaxKind.ReturnStatement:
return getContextualTypeForReturnExpression(node);
case SyntaxKind.CallExpression:
case SyntaxKind.NewExpression:
return getContextualTypeForArgument(node);
case SyntaxKind.TypeAssertionExpression:
return getTypeFromTypeNode((<TypeAssertion>parent).type);
case SyntaxKind.BinaryExpression:
return getContextualTypeForBinaryOperand(node);
case SyntaxKind.PropertyAssignment:
return getContextualTypeForPropertyExpression(node);
case SyntaxKind.ArrayLiteralExpression:
return getContextualTypeForElementExpression(node);
case SyntaxKind.ConditionalExpression:
return getContextualTypeForConditionalOperand(node);
}
return undefined;
}
// If the given type is an object or union type, if that type has a single signature, and if
// that signature is non-generic, return the signature. Otherwise return undefined.
function getNonGenericSignature(type: Type): Signature {
var signatures = getSignaturesOfObjectOrUnionType(type, SignatureKind.Call);
if (signatures.length === 1) {
var signature = signatures[0];
if (!signature.typeParameters) {
return signature;
}
}
}
function isFunctionExpressionOrArrowFunction(node: Node): boolean {
return node.kind === SyntaxKind.FunctionExpression || node.kind === SyntaxKind.ArrowFunction;
}
function getContextualSignatureForFunctionLikeDeclaration(node: FunctionLikeDeclaration): Signature {
// Only function expressions and arrow functions are contextually typed.
return isFunctionExpressionOrArrowFunction(node) ? getContextualSignature(<FunctionExpression>node) : undefined;
}
// Return the contextual signature for a given expression node. A contextual type provides a
// contextual signature if it has a single call signature and if that call signature is non-generic.
// If the contextual type is a union type, get the signature from each type possible and if they are
// all identical ignoring their return type, the result is same signature but with return type as
// union type of return types from these signatures
function getContextualSignature(node: FunctionExpression): Signature {
var type = getContextualType(node);
if (!type) {
return undefined;
}
if (!(type.flags & TypeFlags.Union)) {
return getNonGenericSignature(type);
}
var signatureList: Signature[];
var types = (<UnionType>type).types;
for (var i = 0; i < types.length; i++) {
// The signature set of all constituent type with call signatures should match
// So number of signatures allowed is either 0 or 1
if (signatureList &&
getSignaturesOfObjectOrUnionType(types[i], SignatureKind.Call).length > 1) {
return undefined;
}
var signature = getNonGenericSignature(types[i]);
if (signature) {
if (!signatureList) {
// This signature will contribute to contextual union signature
signatureList = [signature];
}
else if (!compareSignatures(signatureList[0], signature, /*compareReturnTypes*/ false, compareTypes)) {
// Signatures arent identical, do not use
return undefined;
}
else {
// Use this signature for contextual union signature
signatureList.push(signature);
}
}
}
// Result is union of signatures collected (return type is union of return types of this signature set)
var result: Signature;
if (signatureList) {
result = cloneSignature(signatureList[0]);
// Clear resolved return type we possibly got from cloneSignature
result.resolvedReturnType = undefined;
result.unionSignatures = signatureList;
}
return result;
}
// Presence of a contextual type mapper indicates inferential typing, except the identityMapper object is
// used as a special marker for other purposes.
function isInferentialContext(mapper: TypeMapper) {
return mapper && mapper !== identityMapper;
}
function checkArrayLiteral(node: ArrayLiteralExpression, contextualMapper?: TypeMapper): Type {
var elements = node.elements;
if (!elements.length) {
return createArrayType(undefinedType);
}
var elementTypes = map(elements, e => checkExpression(e, contextualMapper));
var contextualType = getContextualType(node);
if (contextualType && contextualTypeIsTupleType(contextualType)) {
return createTupleType(elementTypes);
}
return createArrayType(getUnionType(elementTypes));
}
function isNumericName(name: string) {
// The intent of numeric names is that
// - they are names with text in a numeric form, and that
// - setting properties/indexing with them is always equivalent to doing so with the numeric literal 'numLit',
// acquired by applying the abstract 'ToNumber' operation on the name's text.
//
// The subtlety is in the latter portion, as we cannot reliably say that anything that looks like a numeric literal is a numeric name.
// In fact, it is the case that the text of the name must be equal to 'ToString(numLit)' for this to hold.
//
// Consider the property name '"0xF00D"'. When one indexes with '0xF00D', they are actually indexing with the value of 'ToString(0xF00D)'
// according to the ECMAScript specification, so it is actually as if the user indexed with the string '"61453"'.
// Thus, the text of all numeric literals equivalent to '61543' such as '0xF00D', '0xf00D', '0170015', etc. are not valid numeric names
// because their 'ToString' representation is not equal to their original text.
// This is motivated by ECMA-262 sections 9.3.1, 9.8.1, 11.1.5, and 11.2.1.
//
// Here, we test whether 'ToString(ToNumber(name))' is exactly equal to 'name'.
// The '+' prefix operator is equivalent here to applying the abstract ToNumber operation.
// Applying the 'toString()' method on a number gives us the abstract ToString operation on a number.
//
// Note that this accepts the values 'Infinity', '-Infinity', and 'NaN', and that this is intentional.
// This is desired behavior, because when indexing with them as numeric entities, you are indexing
// with the strings '"Infinity"', '"-Infinity"', and '"NaN"' respectively.
return (+name).toString() === name;
}
function checkObjectLiteral(node: ObjectLiteralExpression, contextualMapper?: TypeMapper): Type {
var members = node.symbol.members;
var properties: SymbolTable = {};
var contextualType = getContextualType(node);
for (var id in members) {
if (hasProperty(members, id)) {
var member = members[id];
if (member.flags & SymbolFlags.Property) {
var memberDecl = <PropertyDeclaration>member.declarations[0];
var type: Type;
if (memberDecl.kind === SyntaxKind.PropertyAssignment) {
type = checkExpression(memberDecl.initializer, contextualMapper);
}
else {
Debug.assert(memberDecl.kind === SyntaxKind.ShorthandPropertyAssignment);
type = memberDecl.name.kind === SyntaxKind.ComputedPropertyName
? unknownType
: checkExpression(<Expression><Node>memberDecl.name, contextualMapper);
}
var prop = <TransientSymbol>createSymbol(SymbolFlags.Property | SymbolFlags.Transient | member.flags, member.name);
prop.declarations = member.declarations;
prop.parent = member.parent;
if (member.valueDeclaration) prop.valueDeclaration = member.valueDeclaration;
prop.type = type;
prop.target = member;
member = prop;
}
else {
// TypeScript 1.0 spec (April 2014)
// A get accessor declaration is processed in the same manner as
// an ordinary function declaration(section 6.1) with no parameters.
// A set accessor declaration is processed in the same manner
// as an ordinary function declaration with a single parameter and a Void return type.
var getAccessor = <AccessorDeclaration>getDeclarationOfKind(member, SyntaxKind.GetAccessor);
if (getAccessor) {
checkAccessorDeclaration(getAccessor);
}
var setAccessor = <AccessorDeclaration>getDeclarationOfKind(member, SyntaxKind.SetAccessor);
if (setAccessor) {
checkAccessorDeclaration(setAccessor);
}
}
properties[member.name] = member;
}
}
var stringIndexType = getIndexType(IndexKind.String);
var numberIndexType = getIndexType(IndexKind.Number);
return createAnonymousType(node.symbol, properties, emptyArray, emptyArray, stringIndexType, numberIndexType);
function getIndexType(kind: IndexKind) {
if (contextualType && contextualTypeHasIndexSignature(contextualType, kind)) {
var propTypes: Type[] = [];
for (var id in properties) {
if (hasProperty(properties, id)) {
if (kind === IndexKind.String || isNumericName(id)) {
var type = getTypeOfSymbol(properties[id]);
if (!contains(propTypes, type)) {
propTypes.push(type);
}
}
}
}
return propTypes.length ? getUnionType(propTypes) : undefinedType;
}
return undefined;
}
}
// If a symbol is a synthesized symbol with no value declaration, we assume it is a property. Example of this are the synthesized
// '.prototype' property as well as synthesized tuple index properties.
function getDeclarationKindFromSymbol(s: Symbol) {
return s.valueDeclaration ? s.valueDeclaration.kind : SyntaxKind.Property;
}
function getDeclarationFlagsFromSymbol(s: Symbol) {
return s.valueDeclaration ? s.valueDeclaration.flags : s.flags & SymbolFlags.Prototype ? NodeFlags.Public | NodeFlags.Static : 0;
}
function checkClassPropertyAccess(node: PropertyAccessExpression | QualifiedName, left: Expression | QualifiedName, type: Type, prop: Symbol) {
var flags = getDeclarationFlagsFromSymbol(prop);
// Public properties are always accessible
if (!(flags & (NodeFlags.Private | NodeFlags.Protected))) {
return;
}
// Property is known to be private or protected at this point
// Get the declaring and enclosing class instance types
var enclosingClassDeclaration = getAncestor(node, SyntaxKind.ClassDeclaration);
var enclosingClass = enclosingClassDeclaration ? <InterfaceType>getDeclaredTypeOfSymbol(getSymbolOfNode(enclosingClassDeclaration)) : undefined;
var declaringClass = <InterfaceType>getDeclaredTypeOfSymbol(prop.parent);
// Private property is accessible if declaring and enclosing class are the same
if (flags & NodeFlags.Private) {
if (declaringClass !== enclosingClass) {
error(node, Diagnostics.Property_0_is_private_and_only_accessible_within_class_1, symbolToString(prop), typeToString(declaringClass));
}
return;
}
// Property is known to be protected at this point
// All protected properties of a supertype are accessible in a super access
if (left.kind === SyntaxKind.SuperKeyword) {
return;
}
// A protected property is accessible in the declaring class and classes derived from it
if (!enclosingClass || !hasBaseType(enclosingClass, declaringClass)) {
error(node, Diagnostics.Property_0_is_protected_and_only_accessible_within_class_1_and_its_subclasses, symbolToString(prop), typeToString(declaringClass));
return;
}
// No further restrictions for static properties
if (flags & NodeFlags.Static) {
return;
}
// An instance property must be accessed through an instance of the enclosing class
if (!(getTargetType(type).flags & (TypeFlags.Class | TypeFlags.Interface) && hasBaseType(<InterfaceType>type, enclosingClass))) {
error(node, Diagnostics.Property_0_is_protected_and_only_accessible_through_an_instance_of_class_1, symbolToString(prop), typeToString(enclosingClass));
}
}
function checkPropertyAccessExpression(node: PropertyAccessExpression) {
return checkPropertyAccessExpressionOrQualifiedName(node, node.expression, node.name);
}
function checkQualifiedName(node: QualifiedName) {
return checkPropertyAccessExpressionOrQualifiedName(node, node.left, node.right);
}
function checkPropertyAccessExpressionOrQualifiedName(node: PropertyAccessExpression | QualifiedName, left: Expression | QualifiedName, right: Identifier) {
var type = checkExpression(left);
if (type === unknownType) return type;
if (type !== anyType) {
var apparentType = getApparentType(getWidenedType(type));
if (apparentType === unknownType) {
// handle cases when type is Type parameter with invalid constraint
return unknownType;
}
var prop = getPropertyOfType(apparentType, right.text);
if (!prop) {
if (right.text) {
error(right, Diagnostics.Property_0_does_not_exist_on_type_1, declarationNameToString(right), typeToString(type));
}
return unknownType;
}
getNodeLinks(node).resolvedSymbol = prop;
if (prop.parent && prop.parent.flags & SymbolFlags.Class) {
// TS 1.0 spec (April 2014): 4.8.2
// - In a constructor, instance member function, instance member accessor, or
// instance member variable initializer where this references a derived class instance,
// a super property access is permitted and must specify a public instance member function of the base class.
// - In a static member function or static member accessor
// where this references the constructor function object of a derived class,
// a super property access is permitted and must specify a public static member function of the base class.
if (left.kind === SyntaxKind.SuperKeyword && getDeclarationKindFromSymbol(prop) !== SyntaxKind.Method) {
error(right, Diagnostics.Only_public_and_protected_methods_of_the_base_class_are_accessible_via_the_super_keyword);
}
else {
checkClassPropertyAccess(node, left, type, prop);
}
}
return getTypeOfSymbol(prop);
}
return anyType;
}
function isValidPropertyAccess(node: PropertyAccessExpression | QualifiedName, propertyName: string): boolean {
var left = node.kind === SyntaxKind.PropertyAccessExpression
? (<PropertyAccessExpression>node).expression
: (<QualifiedName>node).left;
var type = checkExpression(left);
if (type !== unknownType && type !== anyType) {
var prop = getPropertyOfType(getWidenedType(type), propertyName);
if (prop && prop.parent && prop.parent.flags & SymbolFlags.Class) {
if (left.kind === SyntaxKind.SuperKeyword && getDeclarationKindFromSymbol(prop) !== SyntaxKind.Method) {
return false;
}
else {
var diagnosticsCount = diagnostics.length;
checkClassPropertyAccess(node, left, type, prop);
return diagnostics.length === diagnosticsCount
}
}
}
return true;
}
function checkIndexedAccess(node: ElementAccessExpression): Type {
// Obtain base constraint such that we can bail out if the constraint is an unknown type
var objectType = getApparentType(checkExpression(node.expression));
var indexType = node.argumentExpression ? checkExpression(node.argumentExpression) : unknownType;
if (objectType === unknownType) {
return unknownType;
}
if (isConstEnumObjectType(objectType) && node.argumentExpression && node.argumentExpression.kind !== SyntaxKind.StringLiteral) {
error(node.argumentExpression, Diagnostics.Index_expression_arguments_in_const_enums_must_be_of_type_string);
}
// TypeScript 1.0 spec (April 2014): 4.10 Property Access
// - If IndexExpr is a string literal or a numeric literal and ObjExpr's apparent type has a property with the name
// given by that literal(converted to its string representation in the case of a numeric literal), the property access is of the type of that property.
// - Otherwise, if ObjExpr's apparent type has a numeric index signature and IndexExpr is of type Any, the Number primitive type, or an enum type,
// the property access is of the type of that index signature.
// - Otherwise, if ObjExpr's apparent type has a string index signature and IndexExpr is of type Any, the String or Number primitive type, or an enum type,
// the property access is of the type of that index signature.
// - Otherwise, if IndexExpr is of type Any, the String or Number primitive type, or an enum type, the property access is of type Any.
// See if we can index as a property.
if (node.argumentExpression) {
if (node.argumentExpression.kind === SyntaxKind.StringLiteral || node.argumentExpression.kind === SyntaxKind.NumericLiteral) {
var name = (<LiteralExpression>node.argumentExpression).text;
var prop = getPropertyOfType(objectType, name);
if (prop) {
getNodeLinks(node).resolvedSymbol = prop;
return getTypeOfSymbol(prop);
}
}
}
// Check for compatible indexer types.
if (indexType.flags & (TypeFlags.Any | TypeFlags.StringLike | TypeFlags.NumberLike)) {
// Try to use a number indexer.
if (indexType.flags & (TypeFlags.Any | TypeFlags.NumberLike)) {
var numberIndexType = getIndexTypeOfType(objectType, IndexKind.Number);
if (numberIndexType) {
return numberIndexType;
}
}
// Try to use string indexing.
var stringIndexType = getIndexTypeOfType(objectType, IndexKind.String);
if (stringIndexType) {
return stringIndexType;
}
// Fall back to any.
if (compilerOptions.noImplicitAny && objectType !== anyType) {
error(node, Diagnostics.Index_signature_of_object_type_implicitly_has_an_any_type);
}
return anyType;
}
// REVIEW: Users should know the type that was actually used.
error(node, Diagnostics.An_index_expression_argument_must_be_of_type_string_number_or_any);
return unknownType;
}
function resolveUntypedCall(node: CallLikeExpression): Signature {
if (node.kind === SyntaxKind.TaggedTemplateExpression) {
checkExpression((<TaggedTemplateExpression>node).template);
}
else {
forEach((<CallExpression>node).arguments, argument => {
checkExpression(argument);
});
}
return anySignature;
}
function resolveErrorCall(node: CallLikeExpression): Signature {
resolveUntypedCall(node);
return unknownSignature;
}
function hasCorrectArity(node: CallLikeExpression, args: Expression[], signature: Signature) {
var adjustedArgCount: number;
var typeArguments: NodeArray<TypeNode>;
var callIsIncomplete: boolean;
if (node.kind === SyntaxKind.TaggedTemplateExpression) {
var tagExpression = <TaggedTemplateExpression>node;
// Even if the call is incomplete, we'll have a missing expression as our last argument,
// so we can say the count is just the arg list length
adjustedArgCount = args.length;
typeArguments = undefined;
if (tagExpression.template.kind === SyntaxKind.TemplateExpression) {
// If a tagged template expression lacks a tail literal, the call is incomplete.
// Specifically, a template only can end in a TemplateTail or a Missing literal.
var templateExpression = <TemplateExpression>tagExpression.template;
var lastSpan = lastOrUndefined(templateExpression.templateSpans);
Debug.assert(lastSpan !== undefined); // we should always have at least one span.
callIsIncomplete = getFullWidth(lastSpan.literal) === 0 || !!lastSpan.literal.isUnterminated;
}
else {
// If the template didn't end in a backtick, or its beginning occurred right prior to EOF,
// then this might actually turn out to be a TemplateHead in the future;
// so we consider the call to be incomplete.
var templateLiteral = <LiteralExpression>tagExpression.template;
Debug.assert(templateLiteral.kind === SyntaxKind.NoSubstitutionTemplateLiteral);
callIsIncomplete = !!templateLiteral.isUnterminated;
}
}
else {
var callExpression = <CallExpression>node;
if (!callExpression.arguments) {
// This only happens when we have something of the form: 'new C'
Debug.assert(callExpression.kind === SyntaxKind.NewExpression);
return signature.minArgumentCount === 0;
}
// For IDE scenarios we may have an incomplete call, so a trailing comma is tantamount to adding another argument.
adjustedArgCount = callExpression.arguments.hasTrailingComma ? args.length + 1 : args.length;
// If we are missing the close paren, the call is incomplete.
callIsIncomplete = (<CallExpression>callExpression).arguments.end === callExpression.end;
typeArguments = callExpression.typeArguments;
}
Debug.assert(adjustedArgCount !== undefined, "'adjustedArgCount' undefined");
Debug.assert(callIsIncomplete !== undefined, "'callIsIncomplete' undefined");
return checkArity(adjustedArgCount, typeArguments, callIsIncomplete, signature);
/**
* @param adjustedArgCount The "apparent" number of arguments that we will have in this call.
* @param typeArguments Type arguments node of the call if it exists; undefined otherwise.
* @param callIsIncomplete Whether or not a call is unfinished, and we should be "lenient" when we have too few arguments.
* @param signature The signature whose arity we are comparing.
*/
function checkArity(adjustedArgCount: number,
typeArguments: NodeArray<TypeNode>,
callIsIncomplete: boolean,
signature: Signature): boolean {
// Too many arguments implies incorrect arity.
if (!signature.hasRestParameter && adjustedArgCount > signature.parameters.length) {
return false;
}
// If the user supplied type arguments, but the number of type arguments does not match
// the declared number of type parameters, the call has an incorrect arity.
var hasRightNumberOfTypeArgs = !typeArguments ||
(signature.typeParameters && typeArguments.length === signature.typeParameters.length);
if (!hasRightNumberOfTypeArgs) {
return false;
}
// If the call is incomplete, we should skip the lower bound check.
var hasEnoughArguments = adjustedArgCount >= signature.minArgumentCount;
return callIsIncomplete || hasEnoughArguments;
}
}
// If type has a single call signature and no other members, return that signature. Otherwise, return undefined.
function getSingleCallSignature(type: Type): Signature {
if (type.flags & TypeFlags.ObjectType) {
var resolved = resolveObjectOrUnionTypeMembers(<ObjectType>type);
if (resolved.callSignatures.length === 1 && resolved.constructSignatures.length === 0 &&
resolved.properties.length === 0 && !resolved.stringIndexType && !resolved.numberIndexType) {
return resolved.callSignatures[0];
}
}
return undefined;
}
// Instantiate a generic signature in the context of a non-generic signature (section 3.8.5 in TypeScript spec)
function instantiateSignatureInContextOf(signature: Signature, contextualSignature: Signature, contextualMapper: TypeMapper): Signature {
var context = createInferenceContext(signature.typeParameters, /*inferUnionTypes*/ true);
forEachMatchingParameterType(contextualSignature, signature, (source, target) => {
// Type parameters from outer context referenced by source type are fixed by instantiation of the source type
inferTypes(context, instantiateType(source, contextualMapper), target);
});
return getSignatureInstantiation(signature, getInferredTypes(context));
}
function inferTypeArguments(signature: Signature, args: Expression[], excludeArgument?: boolean[]): InferenceContext {
var typeParameters = signature.typeParameters;
var context = createInferenceContext(typeParameters, /*inferUnionTypes*/ false);
var mapper = createInferenceMapper(context);
// First infer from arguments that are not context sensitive
for (var i = 0; i < args.length; i++) {
if (args[i].kind === SyntaxKind.OmittedExpression) {
continue;
}
if (!excludeArgument || excludeArgument[i] === undefined) {
var parameterType = getTypeAtPosition(signature, i);
if (i === 0 && args[i].parent.kind === SyntaxKind.TaggedTemplateExpression) {
inferTypes(context, globalTemplateStringsArrayType, parameterType);
continue;
}
inferTypes(context, checkExpressionWithContextualType(args[i], parameterType, mapper), parameterType);
}
}
// Next, infer from those context sensitive arguments that are no longer excluded
if (excludeArgument) {
for (var i = 0; i < args.length; i++) {
if (args[i].kind === SyntaxKind.OmittedExpression) {
continue;
}
// No need to special-case tagged templates; their excludeArgument value will be 'undefined'.
if (excludeArgument[i] === false) {
var parameterType = getTypeAtPosition(signature, i);
inferTypes(context, checkExpressionWithContextualType(args[i], parameterType, mapper), parameterType);
}
}
}
var inferredTypes = getInferredTypes(context);
// Inference has failed if the inferenceFailureType type is in list of inferences
context.failedTypeParameterIndex = indexOf(inferredTypes, inferenceFailureType);
// Wipe out the inferenceFailureType from the array so that error recovery can work properly
for (var i = 0; i < inferredTypes.length; i++) {
if (inferredTypes[i] === inferenceFailureType) {
inferredTypes[i] = unknownType;
}
}
return context;
}
function checkTypeArguments(signature: Signature, typeArguments: TypeNode[], typeArgumentResultTypes: Type[], reportErrors: boolean): boolean {
var typeParameters = signature.typeParameters;
var typeArgumentsAreAssignable = true;
for (var i = 0; i < typeParameters.length; i++) {
var typeArgNode = typeArguments[i];
var typeArgument = getTypeFromTypeNode(typeArgNode);
// Do not push on this array! It has a preallocated length
typeArgumentResultTypes[i] = typeArgument;
if (typeArgumentsAreAssignable /* so far */) {
var constraint = getConstraintOfTypeParameter(typeParameters[i]);
if (constraint) {
typeArgumentsAreAssignable = checkTypeAssignableTo(typeArgument, constraint, reportErrors ? typeArgNode : undefined,
Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
}
}
}
return typeArgumentsAreAssignable;
}
function checkApplicableSignature(node: CallLikeExpression, args: Node[], signature: Signature, relation: Map<boolean>, excludeArgument: boolean[], reportErrors: boolean) {
for (var i = 0; i < args.length; i++) {
var arg = args[i];
var argType: Type;
if (arg.kind === SyntaxKind.OmittedExpression) {
continue;
}
var paramType = getTypeAtPosition(signature, i);
if (i === 0 && node.kind === SyntaxKind.TaggedTemplateExpression) {
// A tagged template expression has something of a
// "virtual" parameter with the "cooked" strings array type.
argType = globalTemplateStringsArrayType;
}
else {
// String literals get string literal types unless we're reporting errors
argType = arg.kind === SyntaxKind.StringLiteral && !reportErrors
? getStringLiteralType(<LiteralExpression>arg)
: checkExpressionWithContextualType(<LiteralExpression>arg, paramType, excludeArgument && excludeArgument[i] ? identityMapper : undefined);
}
// Use argument expression as error location when reporting errors
var isValidArgument = checkTypeRelatedTo(argType, paramType, relation, reportErrors ? arg : undefined,
Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1);
if (!isValidArgument) {
return false;
}
}
return true;
}
/**
* Returns the effective arguments for an expression that works like a function invokation.
*
* If 'node' is a CallExpression or a NewExpression, then its argument list is returned.
* If 'node' is a TaggedTemplateExpression, a new argument list is constructed from the substitution
* expressions, where the first element of the list is the template for error reporting purposes.
*/
function getEffectiveCallArguments(node: CallLikeExpression): Expression[] {
var args: Expression[];
if (node.kind === SyntaxKind.TaggedTemplateExpression) {
var template = (<TaggedTemplateExpression>node).template;
args = [template];
if (template.kind === SyntaxKind.TemplateExpression) {
forEach((<TemplateExpression>template).templateSpans, span => {
args.push(span.expression);
});
}
}
else {
args = (<CallExpression>node).arguments || emptyArray;
}
return args;
}
function resolveCall(node: CallLikeExpression, signatures: Signature[], candidatesOutArray: Signature[]): Signature {
var isTaggedTemplate = node.kind === SyntaxKind.TaggedTemplateExpression;
var typeArguments = isTaggedTemplate ? undefined : (<CallExpression>node).typeArguments;
forEach(typeArguments, checkSourceElement);
var candidates = candidatesOutArray || [];
// collectCandidates fills up the candidates array directly
collectCandidates();
if (!candidates.length) {
error(node, Diagnostics.Supplied_parameters_do_not_match_any_signature_of_call_target);
return resolveErrorCall(node);
}
var args = getEffectiveCallArguments(node);
// The following applies to any value of 'excludeArgument[i]':
// - true: the argument at 'i' is susceptible to a one-time permanent contextual typing.
// - undefined: the argument at 'i' is *not* susceptible to permanent contextual typing.
// - false: the argument at 'i' *was* and *has been* permanently contextually typed.
//
// The idea is that we will perform type argument inference & assignability checking once
// without using the susceptible parameters that are functions, and once more for each of those
// parameters, contextually typing each as we go along.
//
// For a tagged template, then the first argument be 'undefined' if necessary
// because it represents a TemplateStringsArray.
var excludeArgument: boolean[];
for (var i = isTaggedTemplate ? 1 : 0; i < args.length; i++) {
if (isContextSensitiveExpression(args[i])) {
if (!excludeArgument) {
excludeArgument = new Array(args.length);
}
excludeArgument[i] = true;
}
}
// The following variables are captured and modified by calls to chooseOverload.
// If overload resolution or type argument inference fails, we want to report the
// best error possible. The best error is one which says that an argument was not
// assignable to a parameter. This implies that everything else about the overload
// was fine. So if there is any overload that is only incorrect because of an
// argument, we will report an error on that one.
//
// function foo(s: string) {}
// function foo(n: number) {} // Report argument error on this overload
// function foo() {}
// foo(true);
//
// If none of the overloads even made it that far, there are two possibilities.
// There was a problem with type arguments for some overload, in which case
// report an error on that. Or none of the overloads even had correct arity,
// in which case give an arity error.
//
// function foo<T>(x: T, y: T) {} // Report type argument inference error
// function foo() {}
// foo(0, true);
//
var candidateForArgumentError: Signature;
var candidateForTypeArgumentError: Signature;
var resultOfFailedInference: InferenceContext;
var result: Signature;
// Section 4.12.1:
// if the candidate list contains one or more signatures for which the type of each argument
// expression is a subtype of each corresponding parameter type, the return type of the first
// of those signatures becomes the return type of the function call.
// Otherwise, the return type of the first signature in the candidate list becomes the return
// type of the function call.
//
// Whether the call is an error is determined by assignability of the arguments. The subtype pass
// is just important for choosing the best signature. So in the case where there is only one
// signature, the subtype pass is useless. So skipping it is an optimization.
if (candidates.length > 1) {
result = chooseOverload(candidates, subtypeRelation);
}
if (!result) {
// Reinitialize these pointers for round two
candidateForArgumentError = undefined;
candidateForTypeArgumentError = undefined;
resultOfFailedInference = undefined;
result = chooseOverload(candidates, assignableRelation);
}
if (result) {
return result;
}
// No signatures were applicable. Now report errors based on the last applicable signature with
// no arguments excluded from assignability checks.
// If candidate is undefined, it means that no candidates had a suitable arity. In that case,
// skip the checkApplicableSignature check.
if (candidateForArgumentError) {
// excludeArgument is undefined, in this case also equivalent to [undefined, undefined, ...]
// The importance of excludeArgument is to prevent us from typing function expression parameters
// in arguments too early. If possible, we'd like to only type them once we know the correct
// overload. However, this matters for the case where the call is correct. When the call is
// an error, we don't need to exclude any arguments, although it would cause no harm to do so.
checkApplicableSignature(node, args, candidateForArgumentError, assignableRelation, /*excludeArgument*/ undefined, /*reportErrors*/ true);
}
else if (candidateForTypeArgumentError) {
if (!isTaggedTemplate && (<CallExpression>node).typeArguments) {
checkTypeArguments(candidateForTypeArgumentError, (<CallExpression>node).typeArguments, [], /*reportErrors*/ true)
}
else {
Debug.assert(resultOfFailedInference.failedTypeParameterIndex >= 0);
var failedTypeParameter = candidateForTypeArgumentError.typeParameters[resultOfFailedInference.failedTypeParameterIndex];
var inferenceCandidates = getInferenceCandidates(resultOfFailedInference, resultOfFailedInference.failedTypeParameterIndex);
var diagnosticChainHead = chainDiagnosticMessages(/*details*/ undefined, // details will be provided by call to reportNoCommonSupertypeError
Diagnostics.The_type_argument_for_type_parameter_0_cannot_be_inferred_from_the_usage_Consider_specifying_the_type_arguments_explicitly,
typeToString(failedTypeParameter));
reportNoCommonSupertypeError(inferenceCandidates, (<CallExpression>node).expression || (<TaggedTemplateExpression>node).tag, diagnosticChainHead);
}
}
else {
error(node, Diagnostics.Supplied_parameters_do_not_match_any_signature_of_call_target);
}
// No signature was applicable. We have already reported the errors for the invalid signature.
// If this is a type resolution session, e.g. Language Service, try to get better information that anySignature.
// Pick the first candidate that matches the arity. This way we can get a contextual type for cases like:
// declare function f(a: { xa: number; xb: number; });
// f({ |
if (!fullTypeCheck) {
for (var i = 0, n = candidates.length; i < n; i++) {
if (hasCorrectArity(node, args, candidates[i])) {
return candidates[i];
}
}
}
return resolveErrorCall(node);
function chooseOverload(candidates: Signature[], relation: Map<boolean>) {
for (var i = 0; i < candidates.length; i++) {
if (!hasCorrectArity(node, args, candidates[i])) {
continue;
}
var originalCandidate = candidates[i];
var inferenceResult: InferenceContext;
while (true) {
var candidate = originalCandidate;
if (candidate.typeParameters) {
var typeArgumentTypes: Type[];
var typeArgumentsAreValid: boolean;
if (typeArguments) {
typeArgumentTypes = new Array<Type>(candidate.typeParameters.length);
typeArgumentsAreValid = checkTypeArguments(candidate, typeArguments, typeArgumentTypes, /*reportErrors*/ false)
}
else {
inferenceResult = inferTypeArguments(candidate, args, excludeArgument);
typeArgumentsAreValid = inferenceResult.failedTypeParameterIndex < 0;
typeArgumentTypes = inferenceResult.inferredTypes;
}
if (!typeArgumentsAreValid) {
break;
}
candidate = getSignatureInstantiation(candidate, typeArgumentTypes);
}
if (!checkApplicableSignature(node, args, candidate, relation, excludeArgument, /*reportErrors*/ false)) {
break;
}
var index = excludeArgument ? indexOf(excludeArgument, true) : -1;
if (index < 0) {
return candidate;
}
excludeArgument[index] = false;
}
// A post-mortem of this iteration of the loop. The signature was not applicable,
// so we want to track it as a candidate for reporting an error. If the candidate
// had no type parameters, or had no issues related to type arguments, we can
// report an error based on the arguments. If there was an issue with type
// arguments, then we can only report an error based on the type arguments.
if (originalCandidate.typeParameters) {
var instantiatedCandidate = candidate;
if (typeArgumentsAreValid) {
candidateForArgumentError = instantiatedCandidate;
}
else {
candidateForTypeArgumentError = originalCandidate;
if (!typeArguments) {
resultOfFailedInference = inferenceResult;
}
}
}
else {
Debug.assert(originalCandidate === candidate);
candidateForArgumentError = originalCandidate;
}
}
return undefined;
}
// The candidate list orders groups in reverse, but within a group signatures are kept in declaration order
// A nit here is that we reorder only signatures that belong to the same symbol,
// so order how inherited signatures are processed is still preserved.
// interface A { (x: string): void }
// interface B extends A { (x: 'foo'): string }
// var b: B;
// b('foo') // <- here overloads should be processed as [(x:'foo'): string, (x: string): void]
function collectCandidates(): void {
var result = candidates;
var lastParent: Node;
var lastSymbol: Symbol;
var cutoffPos: number = 0;
var pos: number;
Debug.assert(!result.length);
for (var i = 0; i < signatures.length; i++) {
var signature = signatures[i];
var symbol = signature.declaration && getSymbolOfNode(signature.declaration);
var parent = signature.declaration && signature.declaration.parent;
if (!lastSymbol || symbol === lastSymbol) {
if (lastParent && parent === lastParent) {
pos++;
}
else {
lastParent = parent;
pos = cutoffPos;
}
}
else {
// current declaration belongs to a different symbol
// set cutoffPos so re-orderings in the future won't change result set from 0 to cutoffPos
pos = cutoffPos = result.length;
lastParent = parent;
}
lastSymbol = symbol;
for (var j = result.length; j > pos; j--) {
result[j] = result[j - 1];
}
result[pos] = signature;
}
}
}
function resolveCallExpression(node: CallExpression, candidatesOutArray: Signature[]): Signature {
if (node.expression.kind === SyntaxKind.SuperKeyword) {
var superType = checkSuperExpression(node.expression);
if (superType !== unknownType) {
return resolveCall(node, getSignaturesOfType(superType, SignatureKind.Construct), candidatesOutArray);
}
return resolveUntypedCall(node);
}
var funcType = checkExpression(node.expression);
var apparentType = getApparentType(funcType);
if (apparentType === unknownType) {
// Another error has already been reported
return resolveErrorCall(node);
}
// Technically, this signatures list may be incomplete. We are taking the apparent type,
// but we are not including call signatures that may have been added to the Object or
// Function interface, since they have none by default. This is a bit of a leap of faith
// that the user will not add any.
var callSignatures = getSignaturesOfType(apparentType, SignatureKind.Call);
var constructSignatures = getSignaturesOfType(apparentType, SignatureKind.Construct);
// TS 1.0 spec: 4.12
// If FuncExpr is of type Any, or of an object type that has no call or construct signatures
// but is a subtype of the Function interface, the call is an untyped function call. In an
// untyped function call no TypeArgs are permitted, Args can be any argument list, no contextual
// types are provided for the argument expressions, and the result is always of type Any.
// We exclude union types because we may have a union of function types that happen to have
// no common signatures.
if (funcType === anyType || (!callSignatures.length && !constructSignatures.length && !(funcType.flags & TypeFlags.Union) && isTypeAssignableTo(funcType, globalFunctionType))) {
if (node.typeArguments) {
error(node, Diagnostics.Untyped_function_calls_may_not_accept_type_arguments);
}
return resolveUntypedCall(node);
}
// If FuncExpr's apparent type(section 3.8.1) is a function type, the call is a typed function call.
// TypeScript employs overload resolution in typed function calls in order to support functions
// with multiple call signatures.
if (!callSignatures.length) {
if (constructSignatures.length) {
error(node, Diagnostics.Value_of_type_0_is_not_callable_Did_you_mean_to_include_new, typeToString(funcType));
}
else {
error(node, Diagnostics.Cannot_invoke_an_expression_whose_type_lacks_a_call_signature);
}
return resolveErrorCall(node);
}
return resolveCall(node, callSignatures, candidatesOutArray);
}
function resolveNewExpression(node: NewExpression, candidatesOutArray: Signature[]): Signature {
var expressionType = checkExpression(node.expression);
// TS 1.0 spec: 4.11
// If ConstructExpr is of type Any, Args can be any argument
// list and the result of the operation is of type Any.
if (expressionType === anyType) {
if (node.typeArguments) {
error(node, Diagnostics.Untyped_function_calls_may_not_accept_type_arguments);
}
return resolveUntypedCall(node);
}
// If ConstructExpr's apparent type(section 3.8.1) is an object type with one or
// more construct signatures, the expression is processed in the same manner as a
// function call, but using the construct signatures as the initial set of candidate
// signatures for overload resolution.The result type of the function call becomes
// the result type of the operation.
expressionType = getApparentType(expressionType);
if (expressionType === unknownType) {
// Another error has already been reported
return resolveErrorCall(node);
}
// Technically, this signatures list may be incomplete. We are taking the apparent type,
// but we are not including construct signatures that may have been added to the Object or
// Function interface, since they have none by default. This is a bit of a leap of faith
// that the user will not add any.
var constructSignatures = getSignaturesOfType(expressionType, SignatureKind.Construct);
if (constructSignatures.length) {
return resolveCall(node, constructSignatures, candidatesOutArray);
}
// If ConstructExpr's apparent type is an object type with no construct signatures but
// one or more call signatures, the expression is processed as a function call. A compile-time
// error occurs if the result of the function call is not Void. The type of the result of the
// operation is Any.
var callSignatures = getSignaturesOfType(expressionType, SignatureKind.Call);
if (callSignatures.length) {
var signature = resolveCall(node, callSignatures, candidatesOutArray);
if (getReturnTypeOfSignature(signature) !== voidType) {
error(node, Diagnostics.Only_a_void_function_can_be_called_with_the_new_keyword);
}
return signature;
}
error(node, Diagnostics.Cannot_use_new_with_an_expression_whose_type_lacks_a_call_or_construct_signature);
return resolveErrorCall(node);
}
function resolveTaggedTemplateExpression(node: TaggedTemplateExpression, candidatesOutArray: Signature[]): Signature {
var tagType = checkExpression(node.tag);
var apparentType = getApparentType(tagType);
if (apparentType === unknownType) {
// Another error has already been reported
return resolveErrorCall(node);
}
var callSignatures = getSignaturesOfType(apparentType, SignatureKind.Call);
if (tagType === anyType || (!callSignatures.length && !(tagType.flags & TypeFlags.Union) && isTypeAssignableTo(tagType, globalFunctionType))) {
return resolveUntypedCall(node);
}
if (!callSignatures.length) {
error(node, Diagnostics.Cannot_invoke_an_expression_whose_type_lacks_a_call_signature);
return resolveErrorCall(node);
}
return resolveCall(node, callSignatures, candidatesOutArray);
}
// candidatesOutArray is passed by signature help in the language service, and collectCandidates
// must fill it up with the appropriate candidate signatures
function getResolvedSignature(node: CallLikeExpression, candidatesOutArray?: Signature[]): Signature {
var links = getNodeLinks(node);
// If getResolvedSignature has already been called, we will have cached the resolvedSignature.
// However, it is possible that either candidatesOutArray was not passed in the first time,
// or that a different candidatesOutArray was passed in. Therefore, we need to redo the work
// to correctly fill the candidatesOutArray.
if (!links.resolvedSignature || candidatesOutArray) {
links.resolvedSignature = anySignature;
if (node.kind === SyntaxKind.CallExpression) {
links.resolvedSignature = resolveCallExpression(<CallExpression>node, candidatesOutArray);
}
else if (node.kind === SyntaxKind.NewExpression) {
links.resolvedSignature = resolveNewExpression(<NewExpression>node, candidatesOutArray);
}
else if (node.kind === SyntaxKind.TaggedTemplateExpression) {
links.resolvedSignature = resolveTaggedTemplateExpression(<TaggedTemplateExpression>node, candidatesOutArray);
}
else {
Debug.fail("Branch in 'getResolvedSignature' should be unreachable.");
}
}
return links.resolvedSignature;
}
function checkCallExpression(node: CallExpression): Type {
var signature = getResolvedSignature(node);
if (node.expression.kind === SyntaxKind.SuperKeyword) {
return voidType;
}
if (node.kind === SyntaxKind.NewExpression) {
var declaration = signature.declaration;
if (declaration &&
declaration.kind !== SyntaxKind.Constructor &&
declaration.kind !== SyntaxKind.ConstructSignature &&
declaration.kind !== SyntaxKind.ConstructorType) {
// When resolved signature is a call signature (and not a construct signature) the result type is any
if (compilerOptions.noImplicitAny) {
error(node, Diagnostics.new_expression_whose_target_lacks_a_construct_signature_implicitly_has_an_any_type);
}
return anyType;
}
}
return getReturnTypeOfSignature(signature);
}
function checkTaggedTemplateExpression(node: TaggedTemplateExpression): Type {
return getReturnTypeOfSignature(getResolvedSignature(node));
}
function checkTypeAssertion(node: TypeAssertion): Type {
var exprType = checkExpression(node.expression);
var targetType = getTypeFromTypeNode(node.type);
if (fullTypeCheck && targetType !== unknownType) {
var widenedType = getWidenedType(exprType, /*supressNoImplicitAnyErrors*/ true);
if (!(isTypeAssignableTo(targetType, widenedType))) {
checkTypeAssignableTo(exprType, targetType, node, Diagnostics.Neither_type_0_nor_type_1_is_assignable_to_the_other);
}
}
return targetType;
}
function getTypeAtPosition(signature: Signature, pos: number): Type {
return signature.hasRestParameter ?
pos < signature.parameters.length - 1 ? getTypeOfSymbol(signature.parameters[pos]) : getRestTypeOfSignature(signature) :
pos < signature.parameters.length ? getTypeOfSymbol(signature.parameters[pos]) : anyType;
}
function assignContextualParameterTypes(signature: Signature, context: Signature, mapper: TypeMapper) {
var len = signature.parameters.length - (signature.hasRestParameter ? 1 : 0);
for (var i = 0; i < len; i++) {
var parameter = signature.parameters[i];
var links = getSymbolLinks(parameter);
links.type = instantiateType(getTypeAtPosition(context, i), mapper);
}
if (signature.hasRestParameter && context.hasRestParameter && signature.parameters.length >= context.parameters.length) {
var parameter = signature.parameters[signature.parameters.length - 1];
var links = getSymbolLinks(parameter);
links.type = instantiateType(getTypeOfSymbol(context.parameters[context.parameters.length - 1]), mapper);
}
}
function getReturnTypeFromBody(func: FunctionLikeDeclaration, contextualMapper?: TypeMapper): Type {
var contextualSignature = getContextualSignatureForFunctionLikeDeclaration(func);
if (func.body.kind !== SyntaxKind.FunctionBlock) {
var unwidenedType = checkAndMarkExpression(<Expression>func.body, contextualMapper);
var widenedType = getWidenedType(unwidenedType);
if (fullTypeCheck && compilerOptions.noImplicitAny && !contextualSignature && widenedType !== unwidenedType && getInnermostTypeOfNestedArrayTypes(widenedType) === anyType) {
error(func, Diagnostics.Function_expression_which_lacks_return_type_annotation_implicitly_has_an_0_return_type, typeToString(widenedType));
}
return widenedType;
}
// Aggregate the types of expressions within all the return statements.
var types = checkAndAggregateReturnExpressionTypes(<Block>func.body, contextualMapper);
// Try to return the best common type if we have any return expressions.
if (types.length > 0) {
// When return statements are contextually typed we allow the return type to be a union type. Otherwise we require the
// return expressions to have a best common supertype.
var commonType = contextualSignature ? getUnionType(types) : getCommonSupertype(types);
if (!commonType) {
error(func, Diagnostics.No_best_common_type_exists_among_return_expressions);
return unknownType;
}
var widenedType = getWidenedType(commonType);
// Check and report for noImplicitAny if the best common type implicitly gets widened to an 'any'/arrays-of-'any' type.
if (fullTypeCheck && compilerOptions.noImplicitAny && !contextualSignature && widenedType !== commonType && getInnermostTypeOfNestedArrayTypes(widenedType) === anyType) {
var typeName = typeToString(widenedType);
if (func.name) {
error(func, Diagnostics._0_which_lacks_return_type_annotation_implicitly_has_an_1_return_type, declarationNameToString(func.name), typeName);
}
else {
error(func, Diagnostics.Function_expression_which_lacks_return_type_annotation_implicitly_has_an_0_return_type, typeName);
}
}
return widenedType;
}
return voidType;
}
/// Returns a set of types relating to every return expression relating to a function block.
function checkAndAggregateReturnExpressionTypes(body: Block, contextualMapper?: TypeMapper): Type[] {
var aggregatedTypes: Type[] = [];
forEachReturnStatement(body, returnStatement => {
var expr = returnStatement.expression;
if (expr) {
var type = checkAndMarkExpression(expr, contextualMapper);
if (!contains(aggregatedTypes, type)) {
aggregatedTypes.push(type);
}
}
});
return aggregatedTypes;
}
function bodyContainsAReturnStatement(funcBody: Block) {
return forEachReturnStatement(funcBody, returnStatement => {
return true;
});
}
function bodyContainsSingleThrowStatement(body: Block) {
return (body.statements.length === 1) && (body.statements[0].kind === SyntaxKind.ThrowStatement);
}
// TypeScript Specification 1.0 (6.3) - July 2014
// An explicitly typed function whose return type isn't the Void or the Any type
// must have at least one return statement somewhere in its body.
// An exception to this rule is if the function implementation consists of a single 'throw' statement.
function checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(func: FunctionLikeDeclaration, returnType: Type): void {
if (!fullTypeCheck) {
return;
}
// Functions that return 'void' or 'any' don't need any return expressions.
if (returnType === voidType || returnType === anyType) {
return;
}
// If all we have is a function signature, or an arrow function with an expression body, then there is nothing to check.
if (!func.body || func.body.kind !== SyntaxKind.FunctionBlock) {
return;
}
var bodyBlock = <Block>func.body;
// Ensure the body has at least one return expression.
if (bodyContainsAReturnStatement(bodyBlock)) {
return;
}
// If there are no return expressions, then we need to check if
// the function body consists solely of a throw statement;
// this is to make an exception for unimplemented functions.
if (bodyContainsSingleThrowStatement(bodyBlock)) {
return;
}
// This function does not conform to the specification.
error(func.type, Diagnostics.A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value_or_consist_of_a_single_throw_statement);
}
function checkFunctionExpression(node: FunctionExpression, contextualMapper?: TypeMapper): Type {
// The identityMapper object is used to indicate that function expressions are wildcards
if (contextualMapper === identityMapper) {
return anyFunctionType;
}
var links = getNodeLinks(node);
var type = getTypeOfSymbol(node.symbol);
// Check if function expression is contextually typed and assign parameter types if so
if (!(links.flags & NodeCheckFlags.ContextChecked)) {
var contextualSignature = getContextualSignature(node);
// If a type check is started at a function expression that is an argument of a function call, obtaining the
// contextual type may recursively get back to here during overload resolution of the call. If so, we will have
// already assigned contextual types.
if (!(links.flags & NodeCheckFlags.ContextChecked)) {
links.flags |= NodeCheckFlags.ContextChecked;
if (contextualSignature) {
var signature = getSignaturesOfType(type, SignatureKind.Call)[0];
if (isContextSensitiveExpression(node)) {
assignContextualParameterTypes(signature, contextualSignature, contextualMapper || identityMapper);
}
if (!node.type) {
signature.resolvedReturnType = resolvingType;
var returnType = getReturnTypeFromBody(node, contextualMapper);
if (signature.resolvedReturnType === resolvingType) {
signature.resolvedReturnType = returnType;
}
}
}
checkSignatureDeclaration(node);
}
}
if (fullTypeCheck) {
checkCollisionWithCapturedSuperVariable(node, node.name);
checkCollisionWithCapturedThisVariable(node, node.name);
}
return type;
}
function checkFunctionExpressionBody(node: FunctionExpression) {
if (node.type) {
checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, getTypeFromTypeNode(node.type));
}
if (node.body.kind === SyntaxKind.FunctionBlock) {
checkSourceElement(node.body);
}
else {
var exprType = checkExpression(<Expression>node.body);
if (node.type) {
checkTypeAssignableTo(exprType, getTypeFromTypeNode(node.type), node.body, /*headMessage*/ undefined);
}
checkFunctionExpressionBodies(node.body);
}
}
function checkArithmeticOperandType(operand: Node, type: Type, diagnostic: DiagnosticMessage): boolean {
if (!(type.flags & (TypeFlags.Any | TypeFlags.NumberLike))) {
error(operand, diagnostic);
return false;
}
return true;
}
function checkReferenceExpression(n: Node, invalidReferenceMessage: DiagnosticMessage, constantVarianleMessage: DiagnosticMessage): boolean {
function findSymbol(n: Node): Symbol {
var symbol = getNodeLinks(n).resolvedSymbol;
// Because we got the symbol from the resolvedSymbol property, it might be of kind
// SymbolFlags.ExportValue. In this case it is necessary to get the actual export
// symbol, which will have the correct flags set on it.
return symbol && getExportSymbolOfValueSymbolIfExported(symbol);
}
function isReferenceOrErrorExpression(n: Node): boolean {
// TypeScript 1.0 spec (April 2014):
// Expressions are classified as values or references.
// References are the subset of expressions that are permitted as the target of an assignment.
// Specifically, references are combinations of identifiers(section 4.3), parentheses(section 4.7),
// and property accesses(section 4.10).
// All other expression constructs described in this chapter are classified as values.
switch (n.kind) {
case SyntaxKind.Identifier:
var symbol = findSymbol(n);
// TypeScript 1.0 spec (April 2014): 4.3
// An identifier expression that references a variable or parameter is classified as a reference.
// An identifier expression that references any other kind of entity is classified as a value(and therefore cannot be the target of an assignment).
return !symbol || symbol === unknownSymbol || symbol === argumentsSymbol || (symbol.flags & SymbolFlags.Variable) !== 0;
case SyntaxKind.PropertyAccessExpression:
var symbol = findSymbol(n);
// TypeScript 1.0 spec (April 2014): 4.10
// A property access expression is always classified as a reference.
// NOTE (not in spec): assignment to enum members should not be allowed
return !symbol || symbol === unknownSymbol || (symbol.flags & ~SymbolFlags.EnumMember) !== 0;
case SyntaxKind.ElementAccessExpression:
// old compiler doesn't check indexed assess
return true;
case SyntaxKind.ParenthesizedExpression:
return isReferenceOrErrorExpression((<ParenthesizedExpression>n).expression);
default:
return false;
}
}
function isConstVariableReference(n: Node): boolean {
switch (n.kind) {
case SyntaxKind.Identifier:
case SyntaxKind.PropertyAccessExpression:
var symbol = findSymbol(n);
return symbol && (symbol.flags & SymbolFlags.Variable) !== 0 && (getDeclarationFlagsFromSymbol(symbol) & NodeFlags.Const) !== 0;
case SyntaxKind.ElementAccessExpression:
var index = (<ElementAccessExpression>n).argumentExpression;
var symbol = findSymbol((<ElementAccessExpression>n).expression);
if (symbol && index && index.kind === SyntaxKind.StringLiteral) {
var name = (<LiteralExpression>index).text;
var prop = getPropertyOfType(getTypeOfSymbol(symbol), name);
return prop && (prop.flags & SymbolFlags.Variable) !== 0 && (getDeclarationFlagsFromSymbol(prop) & NodeFlags.Const) !== 0;
}
return false;
case SyntaxKind.ParenthesizedExpression:
return isConstVariableReference((<ParenthesizedExpression>n).expression);
default:
return false;
}
}
if (!isReferenceOrErrorExpression(n)) {
error(n, invalidReferenceMessage);
return false;
}
if (isConstVariableReference(n)) {
error(n, constantVarianleMessage);
return false;
}
return true;
}
function checkDeleteExpression(node: DeleteExpression): Type {
var operandType = checkExpression(node.expression);
return booleanType;
}
function checkTypeOfExpression(node: TypeOfExpression): Type {
var operandType = checkExpression(node.expression);
return stringType;
}
function checkVoidExpression(node: VoidExpression): Type {
var operandType = checkExpression(node.expression);
return undefinedType;
}
function checkPrefixUnaryExpression(node: PrefixUnaryExpression): Type {
var operandType = checkExpression(node.operand);
switch (node.operator) {
case SyntaxKind.PlusToken:
case SyntaxKind.MinusToken:
case SyntaxKind.TildeToken:
return numberType;
case SyntaxKind.ExclamationToken:
return booleanType;
case SyntaxKind.PlusPlusToken:
case SyntaxKind.MinusMinusToken:
var ok = checkArithmeticOperandType(node.operand, operandType, Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
if (ok) {
// run check only if former checks succeeded to avoid reporting cascading errors
checkReferenceExpression(node.operand,
Diagnostics.The_operand_of_an_increment_or_decrement_operator_must_be_a_variable_property_or_indexer,
Diagnostics.The_operand_of_an_increment_or_decrement_operator_cannot_be_a_constant);
}
return numberType;
}
return unknownType;
}
function checkPostfixUnaryExpression(node: PostfixUnaryExpression): Type {
var operandType = checkExpression(node.operand);
var ok = checkArithmeticOperandType(node.operand, operandType, Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
if (ok) {
// run check only if former checks succeeded to avoid reporting cascading errors
checkReferenceExpression(node.operand,
Diagnostics.The_operand_of_an_increment_or_decrement_operator_must_be_a_variable_property_or_indexer,
Diagnostics.The_operand_of_an_increment_or_decrement_operator_cannot_be_a_constant);
}
return numberType;
}
// Return true if type is any, an object type, a type parameter, or a union type composed of only those kinds of types
function isStructuredType(type: Type): boolean {
if (type.flags & TypeFlags.Union) {
return !forEach((<UnionType>type).types, t => !isStructuredType(t));
}
return (type.flags & TypeFlags.Structured) !== 0;
}
function isConstEnumObjectType(type: Type) : boolean {
return type.flags & (TypeFlags.ObjectType | TypeFlags.Anonymous) && type.symbol && isConstEnumSymbol(type.symbol);
}
function isConstEnumSymbol(symbol: Symbol): boolean {
return (symbol.flags & SymbolFlags.ConstEnum) !== 0;
}
function checkInstanceOfExpression(node: BinaryExpression, leftType: Type, rightType: Type): Type {
// TypeScript 1.0 spec (April 2014): 4.15.4
// The instanceof operator requires the left operand to be of type Any, an object type, or a type parameter type,
// and the right operand to be of type Any or a subtype of the 'Function' interface type.
// The result is always of the Boolean primitive type.
// NOTE: do not raise error if leftType is unknown as related error was already reported
if (leftType !== unknownType && !isStructuredType(leftType)) {
error(node.left, Diagnostics.The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
}
// NOTE: do not raise error if right is unknown as related error was already reported
if (rightType !== unknownType && rightType !== anyType && !isTypeSubtypeOf(rightType, globalFunctionType)) {
error(node.right, Diagnostics.The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type);
}
return booleanType;
}
function checkInExpression(node: BinaryExpression, leftType: Type, rightType: Type): Type {
// TypeScript 1.0 spec (April 2014): 4.15.5
// The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
// and the right operand to be of type Any, an object type, or a type parameter type.
// The result is always of the Boolean primitive type.
if (leftType !== anyType && leftType !== stringType && leftType !== numberType) {
error(node.left, Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_types_any_string_or_number);
}
if (!isStructuredType(rightType)) {
error(node.right, Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
}
return booleanType;
}
function checkBinaryExpression(node: BinaryExpression, contextualMapper?: TypeMapper) {
var operator = node.operator;
var leftType = checkExpression(node.left, contextualMapper);
var rightType = checkExpression(node.right, contextualMapper);
switch (operator) {
case SyntaxKind.AsteriskToken:
case SyntaxKind.AsteriskEqualsToken:
case SyntaxKind.SlashToken:
case SyntaxKind.SlashEqualsToken:
case SyntaxKind.PercentToken:
case SyntaxKind.PercentEqualsToken:
case SyntaxKind.MinusToken:
case SyntaxKind.MinusEqualsToken:
case SyntaxKind.LessThanLessThanToken:
case SyntaxKind.LessThanLessThanEqualsToken:
case SyntaxKind.GreaterThanGreaterThanToken:
case SyntaxKind.GreaterThanGreaterThanEqualsToken:
case SyntaxKind.GreaterThanGreaterThanGreaterThanToken:
case SyntaxKind.GreaterThanGreaterThanGreaterThanEqualsToken:
case SyntaxKind.BarToken:
case SyntaxKind.BarEqualsToken:
case SyntaxKind.CaretToken:
case SyntaxKind.CaretEqualsToken:
case SyntaxKind.AmpersandToken:
case SyntaxKind.AmpersandEqualsToken:
// TypeScript 1.0 spec (April 2014): 4.15.1
// These operators require their operands to be of type Any, the Number primitive type,
// or an enum type. Operands of an enum type are treated
// as having the primitive type Number. If one operand is the null or undefined value,
// it is treated as having the type of the other operand.
// The result is always of the Number primitive type.
if (leftType.flags & (TypeFlags.Undefined | TypeFlags.Null)) leftType = rightType;
if (rightType.flags & (TypeFlags.Undefined | TypeFlags.Null)) rightType = leftType;
var suggestedOperator: SyntaxKind;
// if a user tries to apply a bitwise operator to 2 boolean operands
// try and return them a helpful suggestion
if ((leftType.flags & TypeFlags.Boolean) &&
(rightType.flags & TypeFlags.Boolean) &&
(suggestedOperator = getSuggestedBooleanOperator(node.operator)) !== undefined) {
error(node, Diagnostics.The_0_operator_is_not_allowed_for_boolean_types_Consider_using_1_instead, tokenToString(node.operator), tokenToString(suggestedOperator));
}
else {
// otherwise just check each operand separately and report errors as normal
var leftOk = checkArithmeticOperandType(node.left, leftType, Diagnostics.The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type);
var rightOk = checkArithmeticOperandType(node.right, rightType, Diagnostics.The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type);
if (leftOk && rightOk) {
checkAssignmentOperator(numberType);
}
}
return numberType;
case SyntaxKind.PlusToken:
case SyntaxKind.PlusEqualsToken:
// TypeScript 1.0 spec (April 2014): 4.15.2
// The binary + operator requires both operands to be of the Number primitive type or an enum type,
// or at least one of the operands to be of type Any or the String primitive type.
// If one operand is the null or undefined value, it is treated as having the type of the other operand.
if (leftType.flags & (TypeFlags.Undefined | TypeFlags.Null)) leftType = rightType;
if (rightType.flags & (TypeFlags.Undefined | TypeFlags.Null)) rightType = leftType;
var resultType: Type;
if (leftType.flags & TypeFlags.NumberLike && rightType.flags & TypeFlags.NumberLike) {
// Operands of an enum type are treated as having the primitive type Number.
// If both operands are of the Number primitive type, the result is of the Number primitive type.
resultType = numberType;
}
else if (leftType.flags & TypeFlags.StringLike || rightType.flags & TypeFlags.StringLike) {
// If one or both operands are of the String primitive type, the result is of the String primitive type.
resultType = stringType;
}
else if (leftType.flags & TypeFlags.Any || leftType === unknownType || rightType.flags & TypeFlags.Any || rightType === unknownType) {
// Otherwise, the result is of type Any.
// NOTE: unknown type here denotes error type. Old compiler treated this case as any type so do we.
resultType = anyType;
}
if (!resultType) {
reportOperatorError();
return anyType;
}
if (operator === SyntaxKind.PlusEqualsToken) {
checkAssignmentOperator(resultType);
}
return resultType;
case SyntaxKind.EqualsEqualsToken:
case SyntaxKind.ExclamationEqualsToken:
case SyntaxKind.EqualsEqualsEqualsToken:
case SyntaxKind.ExclamationEqualsEqualsToken:
case SyntaxKind.LessThanToken:
case SyntaxKind.GreaterThanToken:
case SyntaxKind.LessThanEqualsToken:
case SyntaxKind.GreaterThanEqualsToken:
if (!isTypeAssignableTo(leftType, rightType) && !isTypeAssignableTo(rightType, leftType)) {
reportOperatorError();
}
return booleanType;
case SyntaxKind.InstanceOfKeyword:
return checkInstanceOfExpression(node, leftType, rightType);
case SyntaxKind.InKeyword:
return checkInExpression(node, leftType, rightType);
case SyntaxKind.AmpersandAmpersandToken:
return rightType;
case SyntaxKind.BarBarToken:
return getUnionType([leftType, rightType]);
case SyntaxKind.EqualsToken:
checkAssignmentOperator(rightType);
return rightType;
case SyntaxKind.CommaToken:
return rightType;
}
function getSuggestedBooleanOperator(operator: SyntaxKind): SyntaxKind {
switch (operator) {
case SyntaxKind.BarToken:
case SyntaxKind.BarEqualsToken:
return SyntaxKind.BarBarToken;
case SyntaxKind.CaretToken:
case SyntaxKind.CaretEqualsToken:
return SyntaxKind.ExclamationEqualsEqualsToken;
case SyntaxKind.AmpersandToken:
case SyntaxKind.AmpersandEqualsToken:
return SyntaxKind.AmpersandAmpersandToken;
default:
return undefined;
}
}
function checkAssignmentOperator(valueType: Type): void {
if (fullTypeCheck && operator >= SyntaxKind.FirstAssignment && operator <= SyntaxKind.LastAssignment) {
// TypeScript 1.0 spec (April 2014): 4.17
// An assignment of the form
// VarExpr = ValueExpr
// requires VarExpr to be classified as a reference
// A compound assignment furthermore requires VarExpr to be classified as a reference (section 4.1)
// and the type of the non - compound operation to be assignable to the type of VarExpr.
var ok = checkReferenceExpression(node.left, Diagnostics.Invalid_left_hand_side_of_assignment_expression, Diagnostics.Left_hand_side_of_assignment_expression_cannot_be_a_constant);
// Use default messages
if (ok) {
// to avoid cascading errors check assignability only if 'isReference' check succeeded and no errors were reported
checkTypeAssignableTo(valueType, leftType, node.left, /*headMessage*/ undefined);
}
}
}
function reportOperatorError() {
error(node, Diagnostics.Operator_0_cannot_be_applied_to_types_1_and_2, tokenToString(node.operator), typeToString(leftType), typeToString(rightType));
}
}
function checkConditionalExpression(node: ConditionalExpression, contextualMapper?: TypeMapper): Type {
checkExpression(node.condition);
var type1 = checkExpression(node.whenTrue, contextualMapper);
var type2 = checkExpression(node.whenFalse, contextualMapper);
return getUnionType([type1, type2]);
}
function checkTemplateExpression(node: TemplateExpression): Type {
// We just want to check each expressions, but we are unconcerned with
// the type of each expression, as any value may be coerced into a string.
// It is worth asking whether this is what we really want though.
// A place where we actually *are* concerned with the expressions' types are
// in tagged templates.
forEach((<TemplateExpression>node).templateSpans, templateSpan => {
checkExpression(templateSpan.expression);
});
return stringType;
}
function checkExpressionWithContextualType(node: Expression, contextualType: Type, contextualMapper?: TypeMapper): Type {
var saveContextualType = node.contextualType;
node.contextualType = contextualType;
var result = checkExpression(node, contextualMapper);
node.contextualType = saveContextualType;
return result;
}
function checkAndMarkExpression(node: Expression, contextualMapper?: TypeMapper): Type {
var result = checkExpression(node, contextualMapper);
getNodeLinks(node).flags |= NodeCheckFlags.TypeChecked;
return result;
}
// Checks an expression and returns its type. The contextualMapper parameter serves two purposes: When
// contextualMapper is not undefined and not equal to the identityMapper function object it indicates that the
// expression is being inferentially typed (section 4.12.2 in spec) and provides the type mapper to use in
// conjunction with the generic contextual type. When contextualMapper is equal to the identityMapper function
// object, it serves as an indicator that all contained function and arrow expressions should be considered to
// have the wildcard function type; this form of type check is used during overload resolution to exclude
// contextually typed function and arrow expressions in the initial phase.
function checkExpression(node: Expression | QualifiedName, contextualMapper?: TypeMapper): Type {
var type = checkExpressionNode(node, contextualMapper);
if (contextualMapper && contextualMapper !== identityMapper && node.kind !== SyntaxKind.QualifiedName) {
var signature = getSingleCallSignature(type);
if (signature && signature.typeParameters) {
var contextualType = getContextualType(<Expression>node);
if (contextualType) {
var contextualSignature = getSingleCallSignature(contextualType);
if (contextualSignature && !contextualSignature.typeParameters) {
type = getOrCreateTypeFromSignature(instantiateSignatureInContextOf(signature, contextualSignature, contextualMapper));
}
}
}
}
if (isConstEnumObjectType(type)) {
// enum object type for const enums are only permitted in:
// - 'left' in property access
// - 'object' in indexed access
// - target in rhs of import statement
var ok =
(node.parent.kind === SyntaxKind.PropertyAccessExpression && (<PropertyAccessExpression>node.parent).expression === node) ||
(node.parent.kind === SyntaxKind.ElementAccessExpression && (<ElementAccessExpression>node.parent).expression === node) ||
((node.kind === SyntaxKind.Identifier || node.kind === SyntaxKind.QualifiedName) && isInRightSideOfImportOrExportAssignment(<Identifier>node));
if (!ok) {
error(node, Diagnostics.const_enums_can_only_be_used_in_property_or_index_access_expressions_or_the_right_hand_side_of_an_import_declaration_or_export_assignment);
}
}
return type;
}
function checkExpressionNode(node: Expression | QualifiedName, contextualMapper: TypeMapper): Type {
switch (node.kind) {
case SyntaxKind.Identifier:
return checkIdentifier(<Identifier>node);
case SyntaxKind.ThisKeyword:
return checkThisExpression(node);
case SyntaxKind.SuperKeyword:
return checkSuperExpression(node);
case SyntaxKind.NullKeyword:
return nullType;
case SyntaxKind.TrueKeyword:
case SyntaxKind.FalseKeyword:
return booleanType;
case SyntaxKind.NumericLiteral:
return numberType;
case SyntaxKind.TemplateExpression:
return checkTemplateExpression(<TemplateExpression>node);
case SyntaxKind.StringLiteral:
case SyntaxKind.NoSubstitutionTemplateLiteral:
return stringType;
case SyntaxKind.RegularExpressionLiteral:
return globalRegExpType;
case SyntaxKind.QualifiedName:
return checkQualifiedName(<QualifiedName>node);
case SyntaxKind.ArrayLiteralExpression:
return checkArrayLiteral(<ArrayLiteralExpression>node, contextualMapper);
case SyntaxKind.ObjectLiteralExpression:
return checkObjectLiteral(<ObjectLiteralExpression>node, contextualMapper);
case SyntaxKind.PropertyAccessExpression:
return checkPropertyAccessExpression(<PropertyAccessExpression>node);
case SyntaxKind.ElementAccessExpression:
return checkIndexedAccess(<ElementAccessExpression>node);
case SyntaxKind.CallExpression:
case SyntaxKind.NewExpression:
return checkCallExpression(<CallExpression>node);
case SyntaxKind.TaggedTemplateExpression:
return checkTaggedTemplateExpression(<TaggedTemplateExpression>node);
case SyntaxKind.TypeAssertionExpression:
return checkTypeAssertion(<TypeAssertion>node);
case SyntaxKind.ParenthesizedExpression:
return checkExpression((<ParenthesizedExpression>node).expression);
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
return checkFunctionExpression(<FunctionExpression>node, contextualMapper);
case SyntaxKind.TypeOfExpression:
return checkTypeOfExpression(<TypeOfExpression>node);
case SyntaxKind.DeleteExpression:
return checkDeleteExpression(<DeleteExpression>node);
case SyntaxKind.VoidExpression:
return checkVoidExpression(<VoidExpression>node);
case SyntaxKind.PrefixUnaryExpression:
return checkPrefixUnaryExpression(<PrefixUnaryExpression>node);
case SyntaxKind.PostfixUnaryExpression:
return checkPostfixUnaryExpression(<PostfixUnaryExpression>node);
case SyntaxKind.BinaryExpression:
return checkBinaryExpression(<BinaryExpression>node, contextualMapper);
case SyntaxKind.ConditionalExpression:
return checkConditionalExpression(<ConditionalExpression>node, contextualMapper);
case SyntaxKind.OmittedExpression:
return undefinedType;
}
return unknownType;
}
// DECLARATION AND STATEMENT TYPE CHECKING
function checkTypeParameter(node: TypeParameterDeclaration) {
checkSourceElement(node.constraint);
if (fullTypeCheck) {
checkTypeParameterHasIllegalReferencesInConstraint(node);
checkTypeNameIsReserved(node.name, Diagnostics.Type_parameter_name_cannot_be_0);
}
// TODO: Check multiple declarations are identical
}
function checkParameter(parameterDeclaration: ParameterDeclaration) {
checkVariableOrParameterDeclaration(parameterDeclaration);
if (fullTypeCheck) {
checkCollisionWithIndexVariableInGeneratedCode(parameterDeclaration, parameterDeclaration.name);
if (parameterDeclaration.flags & (NodeFlags.Public | NodeFlags.Private | NodeFlags.Protected) &&
!(parameterDeclaration.parent.kind === SyntaxKind.Constructor && (<ConstructorDeclaration>parameterDeclaration.parent).body)) {
error(parameterDeclaration, Diagnostics.A_parameter_property_is_only_allowed_in_a_constructor_implementation);
}
if (parameterDeclaration.dotDotDotToken) {
if (!isArrayType(getTypeOfSymbol(parameterDeclaration.symbol))) {
error(parameterDeclaration, Diagnostics.A_rest_parameter_must_be_of_an_array_type);
}
}
else {
if (parameterDeclaration.initializer && !(<FunctionLikeDeclaration>parameterDeclaration.parent).body) {
error(parameterDeclaration, Diagnostics.A_parameter_initializer_is_only_allowed_in_a_function_or_constructor_implementation);
}
}
}
function checkReferencesInInitializer(n: Node): void {
if (n.kind === SyntaxKind.Identifier) {
var referencedSymbol = getNodeLinks(n).resolvedSymbol;
// check FunctionLikeDeclaration.locals (stores parameters\function local variable)
// if it contains entry with a specified name and if this entry matches the resolved symbol
if (referencedSymbol && referencedSymbol !== unknownSymbol && getSymbol(parameterDeclaration.parent.locals, referencedSymbol.name, SymbolFlags.Value) === referencedSymbol) {
if (referencedSymbol.valueDeclaration.kind === SyntaxKind.Parameter) {
if (referencedSymbol.valueDeclaration === parameterDeclaration) {
error(n, Diagnostics.Parameter_0_cannot_be_referenced_in_its_initializer, declarationNameToString(parameterDeclaration.name));
return;
}
var enclosingOrReferencedParameter =
forEach((<FunctionLikeDeclaration>parameterDeclaration.parent).parameters, p => p === parameterDeclaration || p === referencedSymbol.valueDeclaration ? p : undefined);
if (enclosingOrReferencedParameter === referencedSymbol.valueDeclaration) {
// legal case - parameter initializer references some parameter strictly on left of current parameter declaration
return;
}
// fall through to error reporting
}
error(n, Diagnostics.Initializer_of_parameter_0_cannot_reference_identifier_1_declared_after_it, declarationNameToString(parameterDeclaration.name), declarationNameToString(<Identifier>n));
}
}
else {
forEachChild(n, checkReferencesInInitializer);
}
}
if (parameterDeclaration.initializer) {
checkReferencesInInitializer(parameterDeclaration.initializer);
}
}
function checkSignatureDeclaration(node: SignatureDeclaration) {
checkTypeParameters(node.typeParameters);
forEach(node.parameters, checkParameter);
if (node.type) {
checkSourceElement(node.type);
}
if (fullTypeCheck) {
checkCollisionWithArgumentsInGeneratedCode(node);
if (compilerOptions.noImplicitAny && !node.type) {
switch (node.kind) {
case SyntaxKind.ConstructSignature:
error(node, Diagnostics.Construct_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type);
break;
case SyntaxKind.CallSignature:
error(node, Diagnostics.Call_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type);
break;
}
}
}
checkSpecializedSignatureDeclaration(node);
}
function checkTypeForDuplicateIndexSignatures(node: Node) {
if (node.kind === SyntaxKind.InterfaceDeclaration) {
var nodeSymbol = getSymbolOfNode(node);
// in case of merging interface declaration it is possible that we'll enter this check procedure several times for every declaration
// to prevent this run check only for the first declaration of a given kind
if (nodeSymbol.declarations.length > 0 && nodeSymbol.declarations[0] !== node) {
return;
}
}
// TypeScript 1.0 spec (April 2014)
// 3.7.4: An object type can contain at most one string index signature and one numeric index signature.
// 8.5: A class declaration can have at most one string index member declaration and one numeric index member declaration
var indexSymbol = getIndexSymbol(getSymbolOfNode(node));
if (indexSymbol) {
var seenNumericIndexer = false;
var seenStringIndexer = false;
for (var i = 0, len = indexSymbol.declarations.length; i < len; ++i) {
var declaration = <SignatureDeclaration>indexSymbol.declarations[i];
if (declaration.parameters.length == 1 && declaration.parameters[0].type) {
switch (declaration.parameters[0].type.kind) {
case SyntaxKind.StringKeyword:
if (!seenStringIndexer) {
seenStringIndexer = true;
}
else {
error(declaration, Diagnostics.Duplicate_string_index_signature);
}
break;
case SyntaxKind.NumberKeyword:
if (!seenNumericIndexer) {
seenNumericIndexer = true;
}
else {
error(declaration, Diagnostics.Duplicate_number_index_signature);
}
break;
}
}
}
}
}
function checkPropertyDeclaration(node: PropertyDeclaration) {
if (fullTypeCheck) {
checkVariableOrParameterOrPropertyInFullTypeCheck(node);
}
}
function checkMethodDeclaration(node: MethodDeclaration) {
checkFunctionLikeDeclaration(node);
}
function checkConstructorDeclaration(node: ConstructorDeclaration) {
checkSignatureDeclaration(node);
checkSourceElement(node.body);
var symbol = getSymbolOfNode(node);
var firstDeclaration = getDeclarationOfKind(symbol, node.kind);
// Only type check the symbol once
if (node === firstDeclaration) {
checkFunctionOrConstructorSymbol(symbol);
}
// exit early in the case of signature - super checks are not relevant to them
if (!node.body) {
return;
}
if (!fullTypeCheck) {
return;
}
function isSuperCallExpression(n: Node): boolean {
return n.kind === SyntaxKind.CallExpression && (<CallExpression>n).expression.kind === SyntaxKind.SuperKeyword;
}
function containsSuperCall(n: Node): boolean {
if (isSuperCallExpression(n)) {
return true;
}
switch (n.kind) {
case SyntaxKind.FunctionExpression:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ArrowFunction:
case SyntaxKind.ObjectLiteralExpression: return false;
default: return forEachChild(n, containsSuperCall);
}
}
function markThisReferencesAsErrors(n: Node): void {
if (n.kind === SyntaxKind.ThisKeyword) {
error(n, Diagnostics.this_cannot_be_referenced_in_current_location);
}
else if (n.kind !== SyntaxKind.FunctionExpression && n.kind !== SyntaxKind.FunctionDeclaration) {
forEachChild(n, markThisReferencesAsErrors);
}
}
function isInstancePropertyWithInitializer(n: Node): boolean {
return n.kind === SyntaxKind.Property &&
!(n.flags & NodeFlags.Static) &&
!!(<PropertyDeclaration>n).initializer;
}
// TS 1.0 spec (April 2014): 8.3.2
// Constructors of classes with no extends clause may not contain super calls, whereas
// constructors of derived classes must contain at least one super call somewhere in their function body.
if (getClassBaseTypeNode(<ClassDeclaration>node.parent)) {
if (containsSuperCall(node.body)) {
// The first statement in the body of a constructor must be a super call if both of the following are true:
// - The containing class is a derived class.
// - The constructor declares parameter properties
// or the containing class declares instance member variables with initializers.
var superCallShouldBeFirst =
forEach((<ClassDeclaration>node.parent).members, isInstancePropertyWithInitializer) ||
forEach(node.parameters, p => p.flags & (NodeFlags.Public | NodeFlags.Private | NodeFlags.Protected));
if (superCallShouldBeFirst) {
var statements = (<Block>node.body).statements;
if (!statements.length || statements[0].kind !== SyntaxKind.ExpressionStatement || !isSuperCallExpression((<ExpressionStatement>statements[0]).expression)) {
error(node, Diagnostics.A_super_call_must_be_the_first_statement_in_the_constructor_when_a_class_contains_initialized_properties_or_has_parameter_properties);
}
else {
// In such a required super call, it is a compile-time error for argument expressions to reference this.
markThisReferencesAsErrors((<ExpressionStatement>statements[0]).expression);
}
}
}
else {
error(node, Diagnostics.Constructors_for_derived_classes_must_contain_a_super_call);
}
}
}
function checkAccessorDeclaration(node: AccessorDeclaration) {
if (fullTypeCheck) {
if (node.kind === SyntaxKind.GetAccessor) {
if (!isInAmbientContext(node) && node.body && !(bodyContainsAReturnStatement(<Block>node.body) || bodyContainsSingleThrowStatement(<Block>node.body))) {
error(node.name, Diagnostics.A_get_accessor_must_return_a_value_or_consist_of_a_single_throw_statement);
}
}
if (!hasComputedNameButNotSymbol(node)) {
// TypeScript 1.0 spec (April 2014): 8.4.3
// Accessors for the same member name must specify the same accessibility.
var otherKind = node.kind === SyntaxKind.GetAccessor ? SyntaxKind.SetAccessor : SyntaxKind.GetAccessor;
var otherAccessor = <AccessorDeclaration>getDeclarationOfKind(node.symbol, otherKind);
if (otherAccessor) {
if (((node.flags & NodeFlags.AccessibilityModifier) !== (otherAccessor.flags & NodeFlags.AccessibilityModifier))) {
error(node.name, Diagnostics.Getter_and_setter_accessors_do_not_agree_in_visibility);
}
var currentAccessorType = getAnnotatedAccessorType(node);
var otherAccessorType = getAnnotatedAccessorType(otherAccessor);
// TypeScript 1.0 spec (April 2014): 4.5
// If both accessors include type annotations, the specified types must be identical.
if (currentAccessorType && otherAccessorType) {
if (!isTypeIdenticalTo(currentAccessorType, otherAccessorType)) {
error(node, Diagnostics.get_and_set_accessor_must_have_the_same_type);
}
}
}
checkAndStoreTypeOfAccessors(getSymbolOfNode(node));
}
}
checkFunctionLikeDeclaration(node);
}
function checkTypeReference(node: TypeReferenceNode) {
var type = getTypeFromTypeReferenceNode(node);
if (type !== unknownType && node.typeArguments) {
// Do type argument local checks only if referenced type is successfully resolved
var len = node.typeArguments.length;
for (var i = 0; i < len; i++) {
checkSourceElement(node.typeArguments[i]);
var constraint = getConstraintOfTypeParameter((<TypeReference>type).target.typeParameters[i]);
if (fullTypeCheck && constraint) {
var typeArgument = (<TypeReference>type).typeArguments[i];
checkTypeAssignableTo(typeArgument, constraint, node, Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
}
}
}
}
function checkTypeQuery(node: TypeQueryNode) {
getTypeFromTypeQueryNode(node);
}
function checkTypeLiteral(node: TypeLiteralNode) {
forEach(node.members, checkSourceElement);
if (fullTypeCheck) {
var type = getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node);
checkIndexConstraints(type);
checkTypeForDuplicateIndexSignatures(node);
}
}
function checkArrayType(node: ArrayTypeNode) {
checkSourceElement(node.elementType);
}
function checkTupleType(node: TupleTypeNode) {
forEach(node.elementTypes, checkSourceElement);
}
function checkUnionType(node: UnionTypeNode) {
forEach(node.types, checkSourceElement);
}
function isPrivateWithinAmbient(node: Node): boolean {
return (node.flags & NodeFlags.Private) && isInAmbientContext(node);
}
function checkSpecializedSignatureDeclaration(signatureDeclarationNode: SignatureDeclaration): void {
if (!fullTypeCheck) {
return;
}
var signature = getSignatureFromDeclaration(signatureDeclarationNode);
if (!signature.hasStringLiterals) {
return;
}
// TypeScript 1.0 spec (April 2014): 3.7.2.2
// Specialized signatures are not permitted in conjunction with a function body
if ((<FunctionLikeDeclaration>signatureDeclarationNode).body) {
error(signatureDeclarationNode, Diagnostics.A_signature_with_an_implementation_cannot_use_a_string_literal_type);
return;
}
// TypeScript 1.0 spec (April 2014): 3.7.2.4
// Every specialized call or construct signature in an object type must be assignable
// to at least one non-specialized call or construct signature in the same object type
var signaturesToCheck: Signature[];
// Unnamed (call\construct) signatures in interfaces are inherited and not shadowed so examining just node symbol won't give complete answer.
// Use declaring type to obtain full list of signatures.
if (!signatureDeclarationNode.name && signatureDeclarationNode.parent && signatureDeclarationNode.parent.kind === SyntaxKind.InterfaceDeclaration) {
Debug.assert(signatureDeclarationNode.kind === SyntaxKind.CallSignature || signatureDeclarationNode.kind === SyntaxKind.ConstructSignature);
var signatureKind = signatureDeclarationNode.kind === SyntaxKind.CallSignature ? SignatureKind.Call : SignatureKind.Construct;
var containingSymbol = getSymbolOfNode(signatureDeclarationNode.parent);
var containingType = getDeclaredTypeOfSymbol(containingSymbol);
signaturesToCheck = getSignaturesOfType(containingType, signatureKind);
}
else {
signaturesToCheck = getSignaturesOfSymbol(getSymbolOfNode(signatureDeclarationNode));
}
for (var i = 0; i < signaturesToCheck.length; i++) {
var otherSignature = signaturesToCheck[i];
if (!otherSignature.hasStringLiterals && isSignatureAssignableTo(signature, otherSignature)) {
return;
}
}
error(signatureDeclarationNode, Diagnostics.Specialized_overload_signature_is_not_assignable_to_any_non_specialized_signature);
}
function getEffectiveDeclarationFlags(n: Node, flagsToCheck: NodeFlags) {
var flags = n.flags;
if (n.parent.kind !== SyntaxKind.InterfaceDeclaration && isInAmbientContext(n)) {
if (!(flags & NodeFlags.Ambient)) {
// It is nested in an ambient context, which means it is automatically exported
flags |= NodeFlags.Export;
}
flags |= NodeFlags.Ambient;
}
return flags & flagsToCheck;
}
function checkFunctionOrConstructorSymbol(symbol: Symbol): void {
if (!fullTypeCheck) {
return;
}
function getCanonicalOverload(overloads: Declaration[], implementation: FunctionLikeDeclaration) {
// Consider the canonical set of flags to be the flags of the bodyDeclaration or the first declaration
// Error on all deviations from this canonical set of flags
// The caveat is that if some overloads are defined in lib.d.ts, we don't want to
// report the errors on those. To achieve this, we will say that the implementation is
// the canonical signature only if it is in the same container as the first overload
var implementationSharesContainerWithFirstOverload = implementation !== undefined && implementation.parent === overloads[0].parent;
return implementationSharesContainerWithFirstOverload ? implementation : overloads[0];
}
function checkFlagAgreementBetweenOverloads(overloads: Declaration[], implementation: FunctionLikeDeclaration, flagsToCheck: NodeFlags, someOverloadFlags: NodeFlags, allOverloadFlags: NodeFlags): void {
// Error if some overloads have a flag that is not shared by all overloads. To find the
// deviations, we XOR someOverloadFlags with allOverloadFlags
var someButNotAllOverloadFlags = someOverloadFlags ^ allOverloadFlags;
if (someButNotAllOverloadFlags !== 0) {
var canonicalFlags = getEffectiveDeclarationFlags(getCanonicalOverload(overloads, implementation), flagsToCheck);
forEach(overloads, o => {
var deviation = getEffectiveDeclarationFlags(o, flagsToCheck) ^ canonicalFlags;
if (deviation & NodeFlags.Export) {
error(o.name, Diagnostics.Overload_signatures_must_all_be_exported_or_not_exported);
}
else if (deviation & NodeFlags.Ambient) {
error(o.name, Diagnostics.Overload_signatures_must_all_be_ambient_or_non_ambient);
}
else if (deviation & (NodeFlags.Private | NodeFlags.Protected)) {
error(o.name, Diagnostics.Overload_signatures_must_all_be_public_private_or_protected);
}
});
}
}
function checkQuestionTokenAgreementBetweenOverloads(overloads: Declaration[], implementation: FunctionLikeDeclaration, someHaveQuestionToken: boolean, allHaveQuestionToken: boolean): void {
if (someHaveQuestionToken !== allHaveQuestionToken) {
var canonicalHasQuestionToken = hasQuestionToken(getCanonicalOverload(overloads, implementation));
forEach(overloads, o => {
var deviation = hasQuestionToken(o) !== canonicalHasQuestionToken;
if (deviation) {
error(o.name, Diagnostics.Overload_signatures_must_all_be_optional_or_required);
}
});
}
}
var flagsToCheck: NodeFlags = NodeFlags.Export | NodeFlags.Ambient | NodeFlags.Private | NodeFlags.Protected;
var someNodeFlags: NodeFlags = 0;
var allNodeFlags = flagsToCheck;
var someHaveQuestionToken = false;
var allHaveQuestionToken = true;
var hasOverloads = false;
var bodyDeclaration: FunctionLikeDeclaration;
var lastSeenNonAmbientDeclaration: FunctionLikeDeclaration;
var previousDeclaration: FunctionLikeDeclaration;
var declarations = symbol.declarations;
var isConstructor = (symbol.flags & SymbolFlags.Constructor) !== 0;
function reportImplementationExpectedError(node: FunctionLikeDeclaration): void {
if (node.name && getFullWidth(node.name) === 0) {
return;
}
var seen = false;
var subsequentNode = forEachChild(node.parent, c => {
if (seen) {
return c;
}
else {
seen = c === node;
}
});
if (subsequentNode) {
if (subsequentNode.kind === node.kind) {
var errorNode: Node = (<FunctionLikeDeclaration>subsequentNode).name || subsequentNode;
// TODO(jfreeman): These are methods, so handle computed name case
if (node.name && (<FunctionLikeDeclaration>subsequentNode).name && (<Identifier>node.name).text === (<Identifier>(<FunctionLikeDeclaration>subsequentNode).name).text) {
// the only situation when this is possible (same kind\same name but different symbol) - mixed static and instance class members
Debug.assert(node.kind === SyntaxKind.Method);
Debug.assert((node.flags & NodeFlags.Static) !== (subsequentNode.flags & NodeFlags.Static));
var diagnostic = node.flags & NodeFlags.Static ? Diagnostics.Function_overload_must_be_static : Diagnostics.Function_overload_must_not_be_static;
error(errorNode, diagnostic);
return;
}
else if ((<FunctionLikeDeclaration>subsequentNode).body) {
error(errorNode, Diagnostics.Function_implementation_name_must_be_0, declarationNameToString(node.name));
return;
}
}
}
var errorNode: Node = node.name || node;
if (isConstructor) {
error(errorNode, Diagnostics.Constructor_implementation_is_missing);
}
else {
error(errorNode, Diagnostics.Function_implementation_is_missing_or_not_immediately_following_the_declaration);
}
}
// when checking exported function declarations across modules check only duplicate implementations
// names and consistency of modifiers are verified when we check local symbol
var isExportSymbolInsideModule = symbol.parent && symbol.parent.flags & SymbolFlags.Module;
var duplicateFunctionDeclaration = false;
var multipleConstructorImplementation = false;
for (var i = 0; i < declarations.length; i++) {
var node = <FunctionLikeDeclaration>declarations[i];
var inAmbientContext = isInAmbientContext(node);
var inAmbientContextOrInterface = node.parent.kind === SyntaxKind.InterfaceDeclaration || node.parent.kind === SyntaxKind.TypeLiteral || inAmbientContext;
if (inAmbientContextOrInterface) {
// check if declarations are consecutive only if they are non-ambient
// 1. ambient declarations can be interleaved
// i.e. this is legal
// declare function foo();
// declare function bar();
// declare function foo();
// 2. mixing ambient and non-ambient declarations is a separate error that will be reported - do not want to report an extra one
previousDeclaration = undefined;
}
if (node.kind === SyntaxKind.FunctionDeclaration || node.kind === SyntaxKind.Method || node.kind === SyntaxKind.Constructor) {
var currentNodeFlags = getEffectiveDeclarationFlags(node, flagsToCheck);
someNodeFlags |= currentNodeFlags;
allNodeFlags &= currentNodeFlags;
someHaveQuestionToken = someHaveQuestionToken || hasQuestionToken(node);
allHaveQuestionToken = allHaveQuestionToken && hasQuestionToken(node);
if (node.body && bodyDeclaration) {
if (isConstructor) {
multipleConstructorImplementation = true;
}
else {
duplicateFunctionDeclaration = true;
}
}
else if (!isExportSymbolInsideModule && previousDeclaration && previousDeclaration.parent === node.parent && previousDeclaration.end !== node.pos) {
reportImplementationExpectedError(previousDeclaration);
}
if (node.body) {
if (!bodyDeclaration) {
bodyDeclaration = node;
}
}
else {
hasOverloads = true;
}
previousDeclaration = node;
if (!inAmbientContextOrInterface) {
lastSeenNonAmbientDeclaration = node;
}
}
}
if (multipleConstructorImplementation) {
forEach(declarations, declaration => {
error(declaration, Diagnostics.Multiple_constructor_implementations_are_not_allowed);
});
}
if (duplicateFunctionDeclaration) {
forEach(declarations, declaration => {
error(declaration.name, Diagnostics.Duplicate_function_implementation);
});
}
if (!isExportSymbolInsideModule && lastSeenNonAmbientDeclaration && !lastSeenNonAmbientDeclaration.body) {
reportImplementationExpectedError(lastSeenNonAmbientDeclaration);
}
if (hasOverloads) {
checkFlagAgreementBetweenOverloads(declarations, bodyDeclaration, flagsToCheck, someNodeFlags, allNodeFlags);
checkQuestionTokenAgreementBetweenOverloads(declarations, bodyDeclaration, someHaveQuestionToken, allHaveQuestionToken);
if (bodyDeclaration) {
var signatures = getSignaturesOfSymbol(symbol);
var bodySignature = getSignatureFromDeclaration(bodyDeclaration);
// If the implementation signature has string literals, we will have reported an error in
// checkSpecializedSignatureDeclaration
if (!bodySignature.hasStringLiterals) {
// TypeScript 1.0 spec (April 2014): 6.1
// If a function declaration includes overloads, the overloads determine the call
// signatures of the type given to the function object
// and the function implementation signature must be assignable to that type
//
// TypeScript 1.0 spec (April 2014): 3.8.4
// Note that specialized call and construct signatures (section 3.7.2.4) are not significant when determining assignment compatibility
// Consider checking against specialized signatures too. Not doing so creates a type hole:
//
// function g(x: "hi", y: boolean);
// function g(x: string, y: {});
// function g(x: string, y: string) { }
//
// The implementation is completely unrelated to the specialized signature, yet we do not check this.
for (var i = 0, len = signatures.length; i < len; ++i) {
if (!signatures[i].hasStringLiterals && !isSignatureAssignableTo(bodySignature, signatures[i])) {
error(signatures[i].declaration, Diagnostics.Overload_signature_is_not_compatible_with_function_implementation);
break;
}
}
}
}
}
}
function checkExportsOnMergedDeclarations(node: Node): void {
if (!fullTypeCheck) {
return;
}
var symbol: Symbol;
// Exports should be checked only if enclosing module contains both exported and non exported declarations.
// In case if all declarations are non-exported check is unnecessary.
// if localSymbol is defined on node then node itself is exported - check is required
var symbol = node.localSymbol;
if (!symbol) {
// local symbol is undefined => this declaration is non-exported.
// however symbol might contain other declarations that are exported
symbol = getSymbolOfNode(node);
if (!(symbol.flags & SymbolFlags.Export)) {
// this is a pure local symbol (all declarations are non-exported) - no need to check anything
return;
}
}
// run the check only for the first declaration in the list
if (getDeclarationOfKind(symbol, node.kind) !== node) {
return;
}
// we use SymbolFlags.ExportValue, SymbolFlags.ExportType and SymbolFlags.ExportNamespace
// to denote disjoint declarationSpaces (without making new enum type).
var exportedDeclarationSpaces: SymbolFlags = 0;
var nonExportedDeclarationSpaces: SymbolFlags = 0;
forEach(symbol.declarations, d => {
var declarationSpaces = getDeclarationSpaces(d);
if (getEffectiveDeclarationFlags(d, NodeFlags.Export)) {
exportedDeclarationSpaces |= declarationSpaces;
}
else {
nonExportedDeclarationSpaces |= declarationSpaces;
}
});
var commonDeclarationSpace = exportedDeclarationSpaces & nonExportedDeclarationSpaces;
if (commonDeclarationSpace) {
// declaration spaces for exported and non-exported declarations intersect
forEach(symbol.declarations, d => {
if (getDeclarationSpaces(d) & commonDeclarationSpace) {
error(d.name, Diagnostics.Individual_declarations_in_merged_declaration_0_must_be_all_exported_or_all_local, declarationNameToString(d.name));
}
});
}
function getDeclarationSpaces(d: Declaration): SymbolFlags {
switch (d.kind) {
case SyntaxKind.InterfaceDeclaration:
return SymbolFlags.ExportType;
case SyntaxKind.ModuleDeclaration:
return (<ModuleDeclaration>d).name.kind === SyntaxKind.StringLiteral || getModuleInstanceState(d) !== ModuleInstanceState.NonInstantiated
? SymbolFlags.ExportNamespace | SymbolFlags.ExportValue
: SymbolFlags.ExportNamespace;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.EnumDeclaration:
return SymbolFlags.ExportType | SymbolFlags.ExportValue;
case SyntaxKind.ImportDeclaration:
var result: SymbolFlags = 0;
var target = resolveImport(getSymbolOfNode(d));
forEach(target.declarations, d => { result |= getDeclarationSpaces(d); } );
return result;
default:
return SymbolFlags.ExportValue;
}
}
}
function checkFunctionDeclaration(node: FunctionDeclaration): void {
checkFunctionLikeDeclaration(node);
if (fullTypeCheck) {
checkCollisionWithCapturedSuperVariable(node, node.name);
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
}
}
function checkFunctionLikeDeclaration(node: FunctionLikeDeclaration): void {
checkSignatureDeclaration(node);
if (!hasComputedNameButNotSymbol(node)) {
// first we want to check the local symbol that contain this declaration
// - if node.localSymbol !== undefined - this is current declaration is exported and localSymbol points to the local symbol
// - if node.localSymbol === undefined - this node is non-exported so we can just pick the result of getSymbolOfNode
var symbol = getSymbolOfNode(node);
var localSymbol = node.localSymbol || symbol;
var firstDeclaration = getDeclarationOfKind(localSymbol, node.kind);
// Only type check the symbol once
if (node === firstDeclaration) {
checkFunctionOrConstructorSymbol(localSymbol);
}
if (symbol.parent) {
// run check once for the first declaration
if (getDeclarationOfKind(symbol, node.kind) === node) {
// run check on export symbol to check that modifiers agree across all exported declarations
checkFunctionOrConstructorSymbol(symbol);
}
}
}
checkSourceElement(node.body);
if (node.type && !isAccessor(node.kind)) {
checkIfNonVoidFunctionHasReturnExpressionsOrSingleThrowStatment(node, getTypeFromTypeNode(node.type));
}
// If there is no body and no explicit return type, then report an error.
if (fullTypeCheck && compilerOptions.noImplicitAny && !node.body && !node.type) {
// Ignore privates within ambient contexts; they exist purely for documentative purposes to avoid name clashing.
// (e.g. privates within .d.ts files do not expose type information)
if (!isPrivateWithinAmbient(node)) {
var typeName = typeToString(anyType);
if (node.name) {
error(node, Diagnostics._0_which_lacks_return_type_annotation_implicitly_has_an_1_return_type, declarationNameToString(node.name), typeName);
}
else {
error(node, Diagnostics.Function_expression_which_lacks_return_type_annotation_implicitly_has_an_0_return_type, typeName);
}
}
}
}
function checkBlock(node: Block) {
forEach(node.statements, checkSourceElement);
}
function checkCollisionWithArgumentsInGeneratedCode(node: SignatureDeclaration) {
// no rest parameters \ declaration context \ overload - no codegen impact
if (!hasRestParameters(node) || isInAmbientContext(node) || !(<FunctionLikeDeclaration>node).body) {
return;
}
forEach(node.parameters, p => {
if (p.name && p.name.text === argumentsSymbol.name) {
error(p, Diagnostics.Duplicate_identifier_arguments_Compiler_uses_arguments_to_initialize_rest_parameters);
}
});
}
function checkCollisionWithIndexVariableInGeneratedCode(node: Node, name: Identifier) {
if (!(name && name.text === "_i")) {
return;
}
if (node.kind === SyntaxKind.Parameter) {
// report error if parameter has name '_i' when:
// - function has implementation (not a signature)
// - function has rest parameters
// - context is not ambient (otherwise no codegen impact)
if ((<FunctionLikeDeclaration>node.parent).body && hasRestParameters(<FunctionLikeDeclaration>node.parent) && !isInAmbientContext(node)) {
error(node, Diagnostics.Duplicate_identifier_i_Compiler_uses_i_to_initialize_rest_parameter);
}
return;
}
var symbol = getNodeLinks(node).resolvedSymbol;
if (symbol === unknownSymbol) {
return;
}
// we would like to discover cases like one below:
//
// var _i = "!";
// function foo(...a) {
// function bar() {
// var x = { get baz() { return _i; } }
// }
// }
//
// at runtime '_i' referenced in getter will be resolved to the generated index variable '_i' used to initialize rest parameters.
// legitimate case: when '_i' is defined inside the function declaration with rest parameters.
//
// function foo(...a) {
// var _i = "!";
// function bar() {
// var x = { get baz() { return _i; } }
// }
// }
//// if resolved symbol for node has more than one declaration - this is definitely an error
//// (there is nothing value-like in the language that can be nested in function and consists of multiple declarations)
//if (symbol.declarations.length > 1) {
// error(node, Diagnostics.Expression_resolves_to_variable_declaration_i_that_compiler_uses_to_initialize_rest_parameter);
// return;
//}
// short gist of the check:
// - otherwise
// - walk to the top of the tree starting from the 'node'
// - at every step check if 'current' node contains any declaration of original node
// yes - return
// no - check if current declaration is function with rest parameters
// yes - report error since '_i' from this function will shadow '_i' defined in the outer scope
// no - go up to the next level
var current = node;
while (current) {
var definedOnCurrentLevel = forEach(symbol.declarations, d => d.parent === current ? d : undefined);
if (definedOnCurrentLevel) {
return;
}
switch (current.kind) {
// all kinds that might have rest parameters
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.Method:
case SyntaxKind.ArrowFunction:
case SyntaxKind.Constructor:
if (hasRestParameters(<FunctionLikeDeclaration>current)) {
error(node, Diagnostics.Expression_resolves_to_variable_declaration_i_that_compiler_uses_to_initialize_rest_parameter);
return;
}
break;
}
current = current.parent;
}
}
function needCollisionCheckForIdentifier(node: Node, identifier: Identifier, name: string): boolean {
if (!identifier || identifier.text !== name) {
return false;
}
if (node.kind === SyntaxKind.Property ||
node.kind === SyntaxKind.Method ||
node.kind === SyntaxKind.GetAccessor ||
node.kind === SyntaxKind.SetAccessor) {
// it is ok to have member named '_super' or '_this' - member access is always qualified
return false;
}
if (isInAmbientContext(node)) {
// ambient context - no codegen impact
return false;
}
if (node.kind === SyntaxKind.Parameter && !(<FunctionLikeDeclaration>node.parent).body) {
// just an overload - no codegen impact
return false;
}
return true;
}
function checkCollisionWithCapturedThisVariable(node: Node, name: Identifier): void {
if (needCollisionCheckForIdentifier(node, name, "_this")) {
potentialThisCollisions.push(node);
}
}
// this function will run after checking the source file so 'CaptureThis' is correct for all nodes
function checkIfThisIsCapturedInEnclosingScope(node: Node): void {
var current = node;
while (current) {
if (getNodeCheckFlags(current) & NodeCheckFlags.CaptureThis) {
var isDeclaration = node.kind !== SyntaxKind.Identifier;
if (isDeclaration) {
error((<Declaration>node).name, Diagnostics.Duplicate_identifier_this_Compiler_uses_variable_declaration_this_to_capture_this_reference);
}
else {
error(node, Diagnostics.Expression_resolves_to_variable_declaration_this_that_compiler_uses_to_capture_this_reference);
}
return;
}
current = current.parent;
}
}
function checkCollisionWithCapturedSuperVariable(node: Node, name: Identifier) {
if (!needCollisionCheckForIdentifier(node, name, "_super")) {
return;
}
// bubble up and find containing type
var enclosingClass = <ClassDeclaration>getAncestor(node, SyntaxKind.ClassDeclaration);
// if containing type was not found or it is ambient - exit (no codegen)
if (!enclosingClass || isInAmbientContext(enclosingClass)) {
return;
}
if (getClassBaseTypeNode(enclosingClass)) {
var isDeclaration = node.kind !== SyntaxKind.Identifier;
if (isDeclaration) {
error(node, Diagnostics.Duplicate_identifier_super_Compiler_uses_super_to_capture_base_class_reference);
}
else {
error(node, Diagnostics.Expression_resolves_to_super_that_compiler_uses_to_capture_base_class_reference);
}
}
}
function checkCollisionWithRequireExportsInGeneratedCode(node: Node, name: Identifier) {
if (!needCollisionCheckForIdentifier(node, name, "require") && !needCollisionCheckForIdentifier(node, name, "exports")) {
return;
}
// Uninstantiated modules shouldnt do this check
if (node.kind === SyntaxKind.ModuleDeclaration && getModuleInstanceState(node) !== ModuleInstanceState.Instantiated) {
return;
}
// In case of variable declaration, node.parent is variable statement so look at the variable statement's parent
var parent = node.kind === SyntaxKind.VariableDeclaration ? node.parent.parent : node.parent;
if (parent.kind === SyntaxKind.SourceFile && isExternalModule(<SourceFile>parent)) {
// If the declaration happens to be in external module, report error that require and exports are reserved keywords
error(name, Diagnostics.Duplicate_identifier_0_Compiler_reserves_name_1_in_top_level_scope_of_an_external_module,
declarationNameToString(name), declarationNameToString(name));
}
}
function checkCollisionWithConstDeclarations(node: VariableOrParameterDeclaration) {
// Variable declarations are hoisted to the top of their function scope. They can shadow
// block scoped declarations, which bind tighter. this will not be flagged as duplicate definition
// by the binder as the declaration scope is different.
// A non-initialized declaration is a no-op as the block declaration will resolve before the var
// declaration. the problem is if the declaration has an initializer. this will act as a write to the
// block declared value. this is fine for let, but not const.
//
// Only consider declarations with initializers, uninitialized var declarations will not
// step on a const variable.
// Do not consider let and const declarations, as duplicate block-scoped declarations
// are handled by the binder.
// We are only looking for var declarations that step on const declarations from a
// different scope. e.g.:
// var x = 0;
// {
// const x = 0;
// var x = 0;
// }
if (node.initializer && (node.flags & NodeFlags.BlockScoped) === 0) {
var symbol = getSymbolOfNode(node);
if (symbol.flags & SymbolFlags.FunctionScopedVariable) {
var localDeclarationSymbol = resolveName(node, node.name.text, SymbolFlags.Variable, /*nodeNotFoundErrorMessage*/ undefined, /*nameArg*/ undefined);
if (localDeclarationSymbol && localDeclarationSymbol !== symbol && localDeclarationSymbol.flags & SymbolFlags.BlockScopedVariable) {
if (getDeclarationFlagsFromSymbol(localDeclarationSymbol) & NodeFlags.Const) {
error(node, Diagnostics.Cannot_redeclare_block_scoped_variable_0, symbolToString(localDeclarationSymbol));
}
}
}
}
}
function checkVariableOrParameterOrPropertyInFullTypeCheck(node: VariableOrParameterOrPropertyDeclaration) {
Debug.assert(fullTypeCheck);
checkSourceElement(node.type);
if (hasComputedNameButNotSymbol(node)) {
// Just check the initializer, since this property won't contribute to the enclosing type
return node.initializer ? checkAndMarkExpression(node.initializer) : anyType;
}
var symbol = getSymbolOfNode(node);
var type: Type;
if (symbol.valueDeclaration !== node) {
type = getTypeOfVariableOrParameterOrPropertyDeclaration(node);
}
else {
type = getTypeOfVariableOrParameterOrProperty(symbol);
}
if (node.initializer && !(getNodeLinks(node.initializer).flags & NodeCheckFlags.TypeChecked)) {
// Use default messages
checkTypeAssignableTo(checkAndMarkExpression(node.initializer), type, node, /*headMessage*/ undefined);
}
return type;
}
function checkVariableOrParameterDeclaration(node: VariableOrParameterDeclaration) {
if (fullTypeCheck) {
var type = checkVariableOrParameterOrPropertyInFullTypeCheck(node);
checkExportsOnMergedDeclarations(node);
if (node.initializer) {
checkCollisionWithConstDeclarations(node);
}
checkCollisionWithCapturedSuperVariable(node, node.name);
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
var symbol = getSymbolOfNode(node);
if (node !== symbol.valueDeclaration) {
// TypeScript 1.0 spec (April 2014): 5.1
// Multiple declarations for the same variable name in the same declaration space are permitted,
// provided that each declaration associates the same type with the variable.
var typeOfValueDeclaration = getTypeOfVariableOrParameterOrProperty(symbol);
if (typeOfValueDeclaration !== unknownType && type !== unknownType && !isTypeIdenticalTo(typeOfValueDeclaration, type)) {
error(node.name, Diagnostics.Subsequent_variable_declarations_must_have_the_same_type_Variable_0_must_be_of_type_1_but_here_has_type_2, declarationNameToString(node.name), typeToString(typeOfValueDeclaration), typeToString(type));
}
}
}
}
function checkVariableStatement(node: VariableStatement) {
forEach(node.declarations, checkVariableOrParameterDeclaration);
}
function checkExpressionStatement(node: ExpressionStatement) {
checkExpression(node.expression);
}
function checkIfStatement(node: IfStatement) {
checkExpression(node.expression);
checkSourceElement(node.thenStatement);
checkSourceElement(node.elseStatement);
}
function checkDoStatement(node: DoStatement) {
checkSourceElement(node.statement);
checkExpression(node.expression);
}
function checkWhileStatement(node: WhileStatement) {
checkExpression(node.expression);
checkSourceElement(node.statement);
}
function checkForStatement(node: ForStatement) {
if (node.declarations) forEach(node.declarations, checkVariableOrParameterDeclaration);
if (node.initializer) checkExpression(node.initializer);
if (node.condition) checkExpression(node.condition);
if (node.iterator) checkExpression(node.iterator);
checkSourceElement(node.statement);
}
function checkForInStatement(node: ForInStatement) {
// TypeScript 1.0 spec (April 2014): 5.4
// In a 'for-in' statement of the form
// for (var VarDecl in Expr) Statement
// VarDecl must be a variable declaration without a type annotation that declares a variable of type Any,
// and Expr must be an expression of type Any, an object type, or a type parameter type.
if (node.declarations) {
if (node.declarations.length >= 1) {
var decl = node.declarations[0];
checkVariableOrParameterDeclaration(decl);
if (decl.type) {
error(decl, Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_use_a_type_annotation);
}
}
}
// In a 'for-in' statement of the form
// for (Var in Expr) Statement
// Var must be an expression classified as a reference of type Any or the String primitive type,
// and Expr must be an expression of type Any, an object type, or a type parameter type.
if (node.variable) {
var exprType = checkExpression(node.variable);
if (exprType !== anyType && exprType !== stringType) {
error(node.variable, Diagnostics.The_left_hand_side_of_a_for_in_statement_must_be_of_type_string_or_any);
}
else {
// run check only former check succeeded to avoid cascading errors
checkReferenceExpression(node.variable, Diagnostics.Invalid_left_hand_side_in_for_in_statement, Diagnostics.Left_hand_side_of_assignment_expression_cannot_be_a_constant);
}
}
var exprType = checkExpression(node.expression);
// unknownType is returned i.e. if node.expression is identifier whose name cannot be resolved
// in this case error about missing name is already reported - do not report extra one
if (!isStructuredType(exprType) && exprType !== unknownType) {
error(node.expression, Diagnostics.The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter);
}
checkSourceElement(node.statement);
}
function checkBreakOrContinueStatement(node: BreakOrContinueStatement) {
// TODO: Check that target label is valid
}
function checkReturnStatement(node: ReturnStatement) {
if (node.expression && !(getNodeLinks(node.expression).flags & NodeCheckFlags.TypeChecked)) {
var func = getContainingFunction(node);
if (func) {
if (func.kind === SyntaxKind.SetAccessor) {
if (node.expression) {
error(node.expression, Diagnostics.Setters_cannot_return_a_value);
}
}
else {
var returnType = getReturnTypeOfSignature(getSignatureFromDeclaration(func));
// do assignability check only if we short circuited in determining return type
// - function has explicit type annotation
// - function is getter with no type annotation and setter parameter type is used
// - function is a constructor (will be special cased below)
var checkAssignability =
func.type ||
(func.kind === SyntaxKind.GetAccessor && getSetAccessorTypeAnnotationNode(<AccessorDeclaration>getDeclarationOfKind(func.symbol, SyntaxKind.SetAccessor)));
if (checkAssignability) {
checkTypeAssignableTo(checkExpression(node.expression), returnType, node.expression, /*headMessage*/ undefined);
}
else if (func.kind == SyntaxKind.Constructor) {
// constructor doesn't have explicit return type annotation and yet its return type is known - declaring type
// handle constructors and issue specialized error message for them.
if (!isTypeAssignableTo(checkExpression(node.expression), returnType)) {
error(node.expression, Diagnostics.Return_type_of_constructor_signature_must_be_assignable_to_the_instance_type_of_the_class);
}
}
}
}
}
}
function checkWithStatement(node: WithStatement) {
checkExpression(node.expression);
error(node.expression, Diagnostics.All_symbols_within_a_with_block_will_be_resolved_to_any);
}
function checkSwitchStatement(node: SwitchStatement) {
var expressionType = checkExpression(node.expression);
forEach(node.clauses, clause => {
if (fullTypeCheck && clause.expression) {
// TypeScript 1.0 spec (April 2014):5.9
// In a 'switch' statement, each 'case' expression must be of a type that is assignable to or from the type of the 'switch' expression.
var caseType = checkExpression(clause.expression);
if (!isTypeAssignableTo(expressionType, caseType)) {
// check 'expressionType isAssignableTo caseType' failed, try the reversed check and report errors if it fails
checkTypeAssignableTo(caseType, expressionType, clause.expression, /*headMessage*/ undefined);
}
}
forEach(clause.statements, checkSourceElement);
});
}
function checkLabeledStatement(node: LabeledStatement) {
checkSourceElement(node.statement);
}
function checkThrowStatement(node: ThrowStatement) {
checkExpression(node.expression);
}
function checkTryStatement(node: TryStatement) {
checkBlock(node.tryBlock);
if (node.catchBlock) checkBlock(node.catchBlock);
if (node.finallyBlock) checkBlock(node.finallyBlock);
}
function checkIndexConstraints(type: Type) {
function checkIndexConstraintForProperty(prop: Symbol, propertyType: Type, indexDeclaration: Declaration, indexType: Type, indexKind: IndexKind): void {
if (!indexType) {
return;
}
// index is numeric and property name is not valid numeric literal
if (indexKind === IndexKind.Number && !isNumericName(prop.name)) {
return;
}
// perform property check if property or indexer is declared in 'type'
// this allows to rule out cases when both property and indexer are inherited from the base class
var errorNode: Node;
if (prop.parent === type.symbol) {
errorNode = prop.valueDeclaration;
}
else if (indexDeclaration) {
errorNode = indexDeclaration;
}
else if (type.flags & TypeFlags.Interface) {
// for interfaces property and indexer might be inherited from different bases
// check if any base class already has both property and indexer.
// check should be performed only if 'type' is the first type that brings property\indexer together
var someBaseClassHasBothPropertyAndIndexer = forEach((<InterfaceType>type).baseTypes, base => getPropertyOfObjectType(base, prop.name) && getIndexTypeOfType(base, indexKind));
errorNode = someBaseClassHasBothPropertyAndIndexer ? undefined : type.symbol.declarations[0];
}
if (errorNode && !isTypeAssignableTo(propertyType, indexType)) {
var errorMessage =
indexKind === IndexKind.String
? Diagnostics.Property_0_of_type_1_is_not_assignable_to_string_index_type_2
: Diagnostics.Property_0_of_type_1_is_not_assignable_to_numeric_index_type_2;
error(errorNode, errorMessage, symbolToString(prop), typeToString(propertyType), typeToString(indexType));
}
}
var declaredNumberIndexer = getIndexDeclarationOfSymbol(type.symbol, IndexKind.Number);
var declaredStringIndexer = getIndexDeclarationOfSymbol(type.symbol, IndexKind.String);
var stringIndexType = getIndexTypeOfType(type, IndexKind.String);
var numberIndexType = getIndexTypeOfType(type, IndexKind.Number);
if (stringIndexType || numberIndexType) {
forEach(getPropertiesOfObjectType(type), prop => {
var propType = getTypeOfSymbol(prop);
checkIndexConstraintForProperty(prop, propType, declaredStringIndexer, stringIndexType, IndexKind.String);
checkIndexConstraintForProperty(prop, propType, declaredNumberIndexer, numberIndexType, IndexKind.Number);
});
}
var errorNode: Node;
if (stringIndexType && numberIndexType) {
errorNode = declaredNumberIndexer || declaredStringIndexer;
// condition 'errorNode === undefined' may appear if types does not declare nor string neither number indexer
if (!errorNode && (type.flags & TypeFlags.Interface)) {
var someBaseTypeHasBothIndexers = forEach((<InterfaceType>type).baseTypes, base => getIndexTypeOfType(base, IndexKind.String) && getIndexTypeOfType(base, IndexKind.Number));
errorNode = someBaseTypeHasBothIndexers ? undefined : type.symbol.declarations[0];
}
}
if (errorNode && !isTypeAssignableTo(numberIndexType, stringIndexType)) {
error(errorNode, Diagnostics.Numeric_index_type_0_is_not_assignable_to_string_index_type_1,
typeToString(numberIndexType), typeToString(stringIndexType));
}
}
// TODO(jfreeman): Decide what to do for computed properties
function checkTypeNameIsReserved(name: DeclarationName, message: DiagnosticMessage): void {
// TS 1.0 spec (April 2014): 3.6.1
// The predefined type keywords are reserved and cannot be used as names of user defined types.
switch ((<Identifier>name).text) {
case "any":
case "number":
case "boolean":
case "string":
case "void":
error(name, message, (<Identifier>name).text);
}
}
// Check each type parameter and check that list has no duplicate type parameter declarations
function checkTypeParameters(typeParameterDeclarations: TypeParameterDeclaration[]) {
if (typeParameterDeclarations) {
for (var i = 0; i < typeParameterDeclarations.length; i++) {
var node = typeParameterDeclarations[i];
checkTypeParameter(node);
if (fullTypeCheck) {
for (var j = 0; j < i; j++) {
if (typeParameterDeclarations[j].symbol === node.symbol) {
error(node.name, Diagnostics.Duplicate_identifier_0, declarationNameToString(node.name));
}
}
}
}
}
}
function checkClassDeclaration(node: ClassDeclaration) {
checkTypeNameIsReserved(node.name, Diagnostics.Class_name_cannot_be_0);
checkTypeParameters(node.typeParameters);
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
checkExportsOnMergedDeclarations(node);
var symbol = getSymbolOfNode(node);
var type = <InterfaceType>getDeclaredTypeOfSymbol(symbol);
var staticType = <ObjectType>getTypeOfSymbol(symbol);
var baseTypeNode = getClassBaseTypeNode(node);
if (baseTypeNode) {
emitExtends = emitExtends || !isInAmbientContext(node);
checkTypeReference(baseTypeNode);
}
if (type.baseTypes.length) {
if (fullTypeCheck) {
var baseType = type.baseTypes[0];
checkTypeAssignableTo(type, baseType, node.name, Diagnostics.Class_0_incorrectly_extends_base_class_1);
var staticBaseType = getTypeOfSymbol(baseType.symbol);
checkTypeAssignableTo(staticType, getTypeWithoutConstructors(staticBaseType), node.name,
Diagnostics.Class_static_side_0_incorrectly_extends_base_class_static_side_1);
if (baseType.symbol !== resolveEntityName(node, baseTypeNode.typeName, SymbolFlags.Value)) {
error(baseTypeNode, Diagnostics.Type_name_0_in_extends_clause_does_not_reference_constructor_function_for_0, typeToString(baseType));
}
checkKindsOfPropertyMemberOverrides(type, baseType);
}
// Check that base type can be evaluated as expression
checkExpression(baseTypeNode.typeName);
}
var implementedTypeNodes = getClassImplementedTypeNodes(node);
if (implementedTypeNodes) {
forEach(implementedTypeNodes, typeRefNode => {
checkTypeReference(typeRefNode);
if (fullTypeCheck) {
var t = getTypeFromTypeReferenceNode(typeRefNode);
if (t !== unknownType) {
var declaredType = (t.flags & TypeFlags.Reference) ? (<TypeReference>t).target : t;
if (declaredType.flags & (TypeFlags.Class | TypeFlags.Interface)) {
checkTypeAssignableTo(type, t, node.name, Diagnostics.Class_0_incorrectly_implements_interface_1);
}
else {
error(typeRefNode, Diagnostics.A_class_may_only_implement_another_class_or_interface);
}
}
}
});
}
forEach(node.members, checkSourceElement);
if (fullTypeCheck) {
checkIndexConstraints(type);
checkTypeForDuplicateIndexSignatures(node);
}
}
function getTargetSymbol(s: Symbol) {
// if symbol is instantiated its flags are not copied from the 'target'
// so we'll need to get back original 'target' symbol to work with correct set of flags
return s.flags & SymbolFlags.Instantiated ? getSymbolLinks(s).target : s;
}
function checkKindsOfPropertyMemberOverrides(type: InterfaceType, baseType: ObjectType): void {
// TypeScript 1.0 spec (April 2014): 8.2.3
// A derived class inherits all members from its base class it doesn't override.
// Inheritance means that a derived class implicitly contains all non - overridden members of the base class.
// Both public and private property members are inherited, but only public property members can be overridden.
// A property member in a derived class is said to override a property member in a base class
// when the derived class property member has the same name and kind(instance or static)
// as the base class property member.
// The type of an overriding property member must be assignable(section 3.8.4)
// to the type of the overridden property member, or otherwise a compile - time error occurs.
// Base class instance member functions can be overridden by derived class instance member functions,
// but not by other kinds of members.
// Base class instance member variables and accessors can be overridden by
// derived class instance member variables and accessors, but not by other kinds of members.
// NOTE: assignability is checked in checkClassDeclaration
var baseProperties = getPropertiesOfObjectType(baseType);
for (var i = 0, len = baseProperties.length; i < len; ++i) {
var base = getTargetSymbol(baseProperties[i]);
if (base.flags & SymbolFlags.Prototype) {
continue;
}
var derived = getTargetSymbol(getPropertyOfObjectType(type, base.name));
if (derived) {
var baseDeclarationFlags = getDeclarationFlagsFromSymbol(base);
var derivedDeclarationFlags = getDeclarationFlagsFromSymbol(derived);
if ((baseDeclarationFlags & NodeFlags.Private) || (derivedDeclarationFlags & NodeFlags.Private)) {
// either base or derived property is private - not override, skip it
continue;
}
if ((baseDeclarationFlags & NodeFlags.Static) !== (derivedDeclarationFlags & NodeFlags.Static)) {
// value of 'static' is not the same for properties - not override, skip it
continue;
}
if ((base.flags & derived.flags & SymbolFlags.Method) || ((base.flags & SymbolFlags.PropertyOrAccessor) && (derived.flags & SymbolFlags.PropertyOrAccessor))) {
// method is overridden with method or property/accessor is overridden with property/accessor - correct case
continue;
}
var errorMessage: DiagnosticMessage;
if (base.flags & SymbolFlags.Method) {
if (derived.flags & SymbolFlags.Accessor) {
errorMessage = Diagnostics.Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_accessor;
}
else {
Debug.assert((derived.flags & SymbolFlags.Property) !== 0);
errorMessage = Diagnostics.Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_property;
}
}
else if (base.flags & SymbolFlags.Property) {
Debug.assert((derived.flags & SymbolFlags.Method) !== 0);
errorMessage = Diagnostics.Class_0_defines_instance_member_property_1_but_extended_class_2_defines_it_as_instance_member_function;
}
else {
Debug.assert((base.flags & SymbolFlags.Accessor) !== 0);
Debug.assert((derived.flags & SymbolFlags.Method) !== 0);
errorMessage = Diagnostics.Class_0_defines_instance_member_accessor_1_but_extended_class_2_defines_it_as_instance_member_function;
}
error(derived.valueDeclaration.name, errorMessage, typeToString(baseType), symbolToString(base), typeToString(type));
}
}
}
function isAccessor(kind: SyntaxKind): boolean {
return kind === SyntaxKind.GetAccessor || kind === SyntaxKind.SetAccessor;
}
function areTypeParametersIdentical(list1: TypeParameterDeclaration[], list2: TypeParameterDeclaration[]) {
if (!list1 && !list2) {
return true;
}
if (!list1 || !list2 || list1.length !== list2.length) {
return false;
}
// TypeScript 1.0 spec (April 2014):
// When a generic interface has multiple declarations, all declarations must have identical type parameter
// lists, i.e. identical type parameter names with identical constraints in identical order.
for (var i = 0, len = list1.length; i < len; i++) {
var tp1 = list1[i];
var tp2 = list2[i];
if (tp1.name.text !== tp2.name.text) {
return false;
}
if (!tp1.constraint && !tp2.constraint) {
continue;
}
if (!tp1.constraint || !tp2.constraint) {
return false;
}
if (!isTypeIdenticalTo(getTypeFromTypeNode(tp1.constraint), getTypeFromTypeNode(tp2.constraint))) {
return false;
}
}
return true;
}
function checkInheritedPropertiesAreIdentical(type: InterfaceType, typeNode: Node): boolean {
if (!type.baseTypes.length || type.baseTypes.length === 1) {
return true;
}
var seen: Map<{ prop: Symbol; containingType: Type }> = {};
forEach(type.declaredProperties, p => { seen[p.name] = { prop: p, containingType: type }; });
var ok = true;
for (var i = 0, len = type.baseTypes.length; i < len; ++i) {
var base = type.baseTypes[i];
var properties = getPropertiesOfObjectType(base);
for (var j = 0, proplen = properties.length; j < proplen; ++j) {
var prop = properties[j];
if (!hasProperty(seen, prop.name)) {
seen[prop.name] = { prop: prop, containingType: base };
}
else {
var existing = seen[prop.name];
var isInheritedProperty = existing.containingType !== type;
if (isInheritedProperty && !isPropertyIdenticalTo(existing.prop, prop)) {
ok = false;
var typeName1 = typeToString(existing.containingType);
var typeName2 = typeToString(base);
var errorInfo = chainDiagnosticMessages(undefined, Diagnostics.Named_properties_0_of_types_1_and_2_are_not_identical, prop.name, typeName1, typeName2);
errorInfo = chainDiagnosticMessages(errorInfo, Diagnostics.Interface_0_cannot_simultaneously_extend_types_1_and_2, typeToString(type), typeName1, typeName2);
addDiagnostic(createDiagnosticForNodeFromMessageChain(typeNode, errorInfo, program.getCompilerHost().getNewLine()));
}
}
}
}
return ok;
}
function checkInterfaceDeclaration(node: InterfaceDeclaration) {
checkTypeParameters(node.typeParameters);
if (fullTypeCheck) {
checkTypeNameIsReserved(node.name, Diagnostics.Interface_name_cannot_be_0);
checkExportsOnMergedDeclarations(node);
var symbol = getSymbolOfNode(node);
var firstInterfaceDecl = <InterfaceDeclaration>getDeclarationOfKind(symbol, SyntaxKind.InterfaceDeclaration);
if (symbol.declarations.length > 1) {
if (node !== firstInterfaceDecl && !areTypeParametersIdentical(firstInterfaceDecl.typeParameters, node.typeParameters)) {
error(node.name, Diagnostics.All_declarations_of_an_interface_must_have_identical_type_parameters);
}
}
// Only check this symbol once
if (node === firstInterfaceDecl) {
var type = <InterfaceType>getDeclaredTypeOfSymbol(symbol);
// run subsequent checks only if first set succeeded
if (checkInheritedPropertiesAreIdentical(type, node.name)) {
forEach(type.baseTypes, baseType => {
checkTypeAssignableTo(type, baseType, node.name , Diagnostics.Interface_0_incorrectly_extends_interface_1);
});
checkIndexConstraints(type);
}
}
}
forEach(getInterfaceBaseTypeNodes(node), checkTypeReference);
forEach(node.members, checkSourceElement);
if (fullTypeCheck) {
checkTypeForDuplicateIndexSignatures(node);
}
}
function checkTypeAliasDeclaration(node: TypeAliasDeclaration) {
checkTypeNameIsReserved(node.name, Diagnostics.Type_alias_name_cannot_be_0);
checkSourceElement(node.type);
}
function computeEnumMemberValues(node: EnumDeclaration) {
var nodeLinks = getNodeLinks(node);
if (!(nodeLinks.flags & NodeCheckFlags.EnumValuesComputed)) {
var enumSymbol = getSymbolOfNode(node);
var enumType = getDeclaredTypeOfSymbol(enumSymbol);
var autoValue = 0;
var ambient = isInAmbientContext(node);
var enumIsConst = isConst(node);
forEach(node.members, member => {
// TODO(jfreeman): Check that it is not a computed name
if(isNumericName((<Identifier>member.name).text)) {
error(member.name, Diagnostics.An_enum_member_cannot_have_a_numeric_name);
}
var initializer = member.initializer;
if (initializer) {
autoValue = getConstantValueForEnumMemberInitializer(initializer, enumIsConst);
if (autoValue === undefined) {
if (enumIsConst) {
error(initializer, Diagnostics.In_const_enum_declarations_member_initializer_must_be_constant_expression);
}
else if (!ambient) {
// Only here do we need to check that the initializer is assignable to the enum type.
// If it is a constant value (not undefined), it is syntactically constrained to be a number.
// Also, we do not need to check this for ambients because there is already
// a syntax error if it is not a constant.
checkTypeAssignableTo(checkExpression(initializer), enumType, initializer, /*headMessage*/ undefined);
}
}
else if (enumIsConst) {
if (isNaN(autoValue)) {
error(initializer, Diagnostics.const_enum_member_initializer_was_evaluated_to_disallowed_value_NaN);
}
else if (!isFinite(autoValue)) {
error(initializer, Diagnostics.const_enum_member_initializer_was_evaluated_to_a_non_finite_value);
}
}
}
else if (ambient && !enumIsConst) {
autoValue = undefined;
}
if (autoValue !== undefined) {
getNodeLinks(member).enumMemberValue = autoValue++;
}
});
nodeLinks.flags |= NodeCheckFlags.EnumValuesComputed;
}
function getConstantValueForEnumMemberInitializer(initializer: Expression, enumIsConst: boolean): number {
return evalConstant(initializer);
function evalConstant(e: Node): number {
switch (e.kind) {
case SyntaxKind.PrefixUnaryExpression:
var value = evalConstant((<PrefixUnaryExpression>e).operand);
if (value === undefined) {
return undefined;
}
switch ((<PrefixUnaryExpression>e).operator) {
case SyntaxKind.PlusToken: return value;
case SyntaxKind.MinusToken: return -value;
case SyntaxKind.TildeToken: return enumIsConst ? ~value : undefined;
}
return undefined;
case SyntaxKind.BinaryExpression:
if (!enumIsConst) {
return undefined;
}
var left = evalConstant((<BinaryExpression>e).left);
if (left === undefined) {
return undefined;
}
var right = evalConstant((<BinaryExpression>e).right);
if (right === undefined) {
return undefined;
}
switch ((<BinaryExpression>e).operator) {
case SyntaxKind.BarToken: return left | right;
case SyntaxKind.AmpersandToken: return left & right;
case SyntaxKind.GreaterThanGreaterThanToken: return left >> right;
case SyntaxKind.GreaterThanGreaterThanGreaterThanToken: return left >>> right;
case SyntaxKind.LessThanLessThanToken: return left << right;
case SyntaxKind.CaretToken: return left ^ right;
case SyntaxKind.AsteriskToken: return left * right;
case SyntaxKind.SlashToken: return left / right;
case SyntaxKind.PlusToken: return left + right;
case SyntaxKind.MinusToken: return left - right;
case SyntaxKind.PercentToken: return left % right;
}
return undefined;
case SyntaxKind.NumericLiteral:
return +(<LiteralExpression>e).text;
case SyntaxKind.ParenthesizedExpression:
return enumIsConst ? evalConstant((<ParenthesizedExpression>e).expression) : undefined;
case SyntaxKind.Identifier:
case SyntaxKind.ElementAccessExpression:
case SyntaxKind.PropertyAccessExpression:
if (!enumIsConst) {
return undefined;
}
var member = initializer.parent;
var currentType = getTypeOfSymbol(getSymbolOfNode(member.parent));
var enumType: Type;
var propertyName: string;
if (e.kind === SyntaxKind.Identifier) {
// unqualified names can refer to member that reside in different declaration of the enum so just doing name resolution won't work.
// instead pick current enum type and later try to fetch member from the type
enumType = currentType;
propertyName = (<Identifier>e).text;
}
else {
if (e.kind === SyntaxKind.ElementAccessExpression) {
if ((<ElementAccessExpression>e).argumentExpression === undefined ||
(<ElementAccessExpression>e).argumentExpression.kind !== SyntaxKind.StringLiteral) {
return undefined;
}
var enumType = getTypeOfNode((<ElementAccessExpression>e).expression);
propertyName = (<LiteralExpression>(<ElementAccessExpression>e).argumentExpression).text;
}
else {
var enumType = getTypeOfNode((<PropertyAccessExpression>e).expression);
propertyName = (<PropertyAccessExpression>e).name.text;
}
if (enumType !== currentType) {
return undefined;
}
}
if (propertyName === undefined) {
return undefined;
}
var property = getPropertyOfObjectType(enumType, propertyName);
if (!property || !(property.flags & SymbolFlags.EnumMember)) {
return undefined;
}
var propertyDecl = property.valueDeclaration;
// self references are illegal
if (member === propertyDecl) {
return undefined;
}
// illegal case: forward reference
if (!isDefinedBefore(propertyDecl, member)) {
return undefined;
}
return <number>getNodeLinks(propertyDecl).enumMemberValue;
}
}
}
}
function checkEnumDeclaration(node: EnumDeclaration) {
if (!fullTypeCheck) {
return;
}
checkTypeNameIsReserved(node.name, Diagnostics.Enum_name_cannot_be_0);
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
checkExportsOnMergedDeclarations(node);
computeEnumMemberValues(node);
// Spec 2014 - Section 9.3:
// It isn't possible for one enum declaration to continue the automatic numbering sequence of another,
// and when an enum type has multiple declarations, only one declaration is permitted to omit a value
// for the first member.
//
// Only perform this check once per symbol
var enumSymbol = getSymbolOfNode(node);
var firstDeclaration = getDeclarationOfKind(enumSymbol, node.kind);
if (node === firstDeclaration) {
if (enumSymbol.declarations.length > 1) {
var enumIsConst = isConst(node);
// check that const is placed\omitted on all enum declarations
forEach(enumSymbol.declarations, decl => {
if (isConstEnumDeclaration(decl) !== enumIsConst) {
error(decl.name, Diagnostics.Enum_declarations_must_all_be_const_or_non_const);
}
});
}
var seenEnumMissingInitialInitializer = false;
forEach(enumSymbol.declarations, declaration => {
// return true if we hit a violation of the rule, false otherwise
if (declaration.kind !== SyntaxKind.EnumDeclaration) {
return false;
}
var enumDeclaration = <EnumDeclaration>declaration;
if (!enumDeclaration.members.length) {
return false;
}
var firstEnumMember = enumDeclaration.members[0];
if (!firstEnumMember.initializer) {
if (seenEnumMissingInitialInitializer) {
error(firstEnumMember.name, Diagnostics.In_an_enum_with_multiple_declarations_only_one_declaration_can_omit_an_initializer_for_its_first_enum_element);
}
else {
seenEnumMissingInitialInitializer = true;
}
}
});
}
}
function getFirstNonAmbientClassOrFunctionDeclaration(symbol: Symbol): Declaration {
var declarations = symbol.declarations;
for (var i = 0; i < declarations.length; i++) {
var declaration = declarations[i];
if ((declaration.kind === SyntaxKind.ClassDeclaration || (declaration.kind === SyntaxKind.FunctionDeclaration && (<FunctionLikeDeclaration>declaration).body)) && !isInAmbientContext(declaration)) {
return declaration;
}
}
return undefined;
}
function checkModuleDeclaration(node: ModuleDeclaration) {
if (fullTypeCheck) {
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
checkExportsOnMergedDeclarations(node);
var symbol = getSymbolOfNode(node);
if (symbol.flags & SymbolFlags.ValueModule && symbol.declarations.length > 1 && !isInAmbientContext(node)) {
var classOrFunc = getFirstNonAmbientClassOrFunctionDeclaration(symbol);
if (classOrFunc) {
if (getSourceFileOfNode(node) !== getSourceFileOfNode(classOrFunc)) {
error(node.name, Diagnostics.A_module_declaration_cannot_be_in_a_different_file_from_a_class_or_function_with_which_it_is_merged);
}
else if (node.pos < classOrFunc.pos) {
error(node.name, Diagnostics.A_module_declaration_cannot_be_located_prior_to_a_class_or_function_with_which_it_is_merged);
}
}
}
if (node.name.kind === SyntaxKind.StringLiteral) {
if (!isGlobalSourceFile(node.parent)) {
error(node.name, Diagnostics.Ambient_external_modules_cannot_be_nested_in_other_modules);
}
if (isExternalModuleNameRelative(node.name.text)) {
error(node.name, Diagnostics.Ambient_external_module_declaration_cannot_specify_relative_module_name);
}
}
}
checkSourceElement(node.body);
}
function getFirstIdentifier(node: EntityName): Identifier {
while (node.kind === SyntaxKind.QualifiedName) {
node = (<QualifiedName>node).left;
}
return <Identifier>node;
}
function checkImportDeclaration(node: ImportDeclaration) {
checkCollisionWithCapturedThisVariable(node, node.name);
checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
var symbol = getSymbolOfNode(node);
var target: Symbol;
if (isInternalModuleImportDeclaration(node)) {
target = resolveImport(symbol);
// Import declaration for an internal module
if (target !== unknownSymbol) {
if (target.flags & SymbolFlags.Value) {
// Target is a value symbol, check that it is not hidden by a local declaration with the same name and
// ensure it can be evaluated as an expression
var moduleName = getFirstIdentifier(<EntityName>node.moduleReference);
if (resolveEntityName(node, moduleName, SymbolFlags.Value | SymbolFlags.Namespace).flags & SymbolFlags.Namespace) {
checkExpression(<EntityName>node.moduleReference);
}
else {
error(moduleName, Diagnostics.Module_0_is_hidden_by_a_local_declaration_with_the_same_name, declarationNameToString(moduleName));
}
}
if (target.flags & SymbolFlags.Type) {
checkTypeNameIsReserved(node.name, Diagnostics.Import_name_cannot_be_0);
}
}
}
else {
// Import declaration for an external module
if (node.parent.kind === SyntaxKind.SourceFile) {
target = resolveImport(symbol);
}
else if (node.parent.kind === SyntaxKind.ModuleBlock && (<ModuleDeclaration>node.parent.parent).name.kind === SyntaxKind.StringLiteral) {
// TypeScript 1.0 spec (April 2013): 12.1.6
// An ExternalImportDeclaration in an AmbientExternalModuleDeclaration may reference
// other external modules only through top - level external module names.
// Relative external module names are not permitted.
if (getExternalModuleImportDeclarationExpression(node).kind === SyntaxKind.StringLiteral) {
if (isExternalModuleNameRelative((<LiteralExpression>getExternalModuleImportDeclarationExpression(node)).text)) {
error(node, Diagnostics.Import_declaration_in_an_ambient_external_module_declaration_cannot_reference_external_module_through_relative_external_module_name);
target = unknownSymbol;
}
else {
target = resolveImport(symbol);
}
}
else {
target = unknownSymbol;
}
}
else {
// Parent is an internal module (syntax error is already reported)
target = unknownSymbol;
}
}
if (target !== unknownSymbol) {
var excludedMeanings =
(symbol.flags & SymbolFlags.Value ? SymbolFlags.Value : 0) |
(symbol.flags & SymbolFlags.Type ? SymbolFlags.Type : 0) |
(symbol.flags & SymbolFlags.Namespace ? SymbolFlags.Namespace : 0);
if (target.flags & excludedMeanings) {
error(node, Diagnostics.Import_declaration_conflicts_with_local_declaration_of_0, symbolToString(symbol));
}
}
}
function checkExportAssignment(node: ExportAssignment) {
var container = node.parent;
if (container.kind !== SyntaxKind.SourceFile) {
// In a module, the immediate parent will be a block, so climb up one more parent
container = container.parent;
}
checkTypeOfExportAssignmentSymbol(getSymbolOfNode(container));
}
function checkSourceElement(node: Node): void {
if (!node) return;
switch (node.kind) {
case SyntaxKind.TypeParameter:
return checkTypeParameter(<TypeParameterDeclaration>node);
case SyntaxKind.Parameter:
return checkParameter(<ParameterDeclaration>node);
case SyntaxKind.Property:
return checkPropertyDeclaration(<PropertyDeclaration>node);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
return checkSignatureDeclaration(<SignatureDeclaration>node);
case SyntaxKind.Method:
return checkMethodDeclaration(<MethodDeclaration>node);
case SyntaxKind.Constructor:
return checkConstructorDeclaration(<ConstructorDeclaration>node);
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
return checkAccessorDeclaration(<AccessorDeclaration>node);
case SyntaxKind.TypeReference:
return checkTypeReference(<TypeReferenceNode>node);
case SyntaxKind.TypeQuery:
return checkTypeQuery(<TypeQueryNode>node);
case SyntaxKind.TypeLiteral:
return checkTypeLiteral(<TypeLiteralNode>node);
case SyntaxKind.ArrayType:
return checkArrayType(<ArrayTypeNode>node);
case SyntaxKind.TupleType:
return checkTupleType(<TupleTypeNode>node);
case SyntaxKind.UnionType:
return checkUnionType(<UnionTypeNode>node);
case SyntaxKind.ParenthesizedType:
return checkSourceElement((<ParenthesizedTypeNode>node).type);
case SyntaxKind.FunctionDeclaration:
return checkFunctionDeclaration(<FunctionDeclaration>node);
case SyntaxKind.Block:
return checkBlock(<Block>node);
case SyntaxKind.FunctionBlock:
case SyntaxKind.ModuleBlock:
return checkBody(<Block>node);
case SyntaxKind.VariableStatement:
return checkVariableStatement(<VariableStatement>node);
case SyntaxKind.ExpressionStatement:
return checkExpressionStatement(<ExpressionStatement>node);
case SyntaxKind.IfStatement:
return checkIfStatement(<IfStatement>node);
case SyntaxKind.DoStatement:
return checkDoStatement(<DoStatement>node);
case SyntaxKind.WhileStatement:
return checkWhileStatement(<WhileStatement>node);
case SyntaxKind.ForStatement:
return checkForStatement(<ForStatement>node);
case SyntaxKind.ForInStatement:
return checkForInStatement(<ForInStatement>node);
case SyntaxKind.ContinueStatement:
case SyntaxKind.BreakStatement:
return checkBreakOrContinueStatement(<BreakOrContinueStatement>node);
case SyntaxKind.ReturnStatement:
return checkReturnStatement(<ReturnStatement>node);
case SyntaxKind.WithStatement:
return checkWithStatement(<WithStatement>node);
case SyntaxKind.SwitchStatement:
return checkSwitchStatement(<SwitchStatement>node);
case SyntaxKind.LabeledStatement:
return checkLabeledStatement(<LabeledStatement>node);
case SyntaxKind.ThrowStatement:
return checkThrowStatement(<ThrowStatement>node);
case SyntaxKind.TryStatement:
return checkTryStatement(<TryStatement>node);
case SyntaxKind.VariableDeclaration:
return Debug.fail("Checker encountered variable declaration");
case SyntaxKind.ClassDeclaration:
return checkClassDeclaration(<ClassDeclaration>node);
case SyntaxKind.InterfaceDeclaration:
return checkInterfaceDeclaration(<InterfaceDeclaration>node);
case SyntaxKind.TypeAliasDeclaration:
return checkTypeAliasDeclaration(<TypeAliasDeclaration>node);
case SyntaxKind.EnumDeclaration:
return checkEnumDeclaration(<EnumDeclaration>node);
case SyntaxKind.ModuleDeclaration:
return checkModuleDeclaration(<ModuleDeclaration>node);
case SyntaxKind.ImportDeclaration:
return checkImportDeclaration(<ImportDeclaration>node);
case SyntaxKind.ExportAssignment:
return checkExportAssignment(<ExportAssignment>node);
}
}
// Function expression bodies are checked after all statements in the enclosing body. This is to ensure
// constructs like the following are permitted:
// var foo = function () {
// var s = foo();
// return "hello";
// }
// Here, performing a full type check of the body of the function expression whilst in the process of
// determining the type of foo would cause foo to be given type any because of the recursive reference.
// Delaying the type check of the body ensures foo has been assigned a type.
function checkFunctionExpressionBodies(node: Node): void {
switch (node.kind) {
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
forEach((<FunctionLikeDeclaration>node).parameters, checkFunctionExpressionBodies);
checkFunctionExpressionBody(<FunctionExpression>node);
break;
case SyntaxKind.Method:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
forEach((<FunctionLikeDeclaration>node).parameters, checkFunctionExpressionBodies);
break;
case SyntaxKind.WithStatement:
checkFunctionExpressionBodies((<WithStatement>node).expression);
break;
case SyntaxKind.Parameter:
case SyntaxKind.Property:
case SyntaxKind.ArrayLiteralExpression:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.PropertyAssignment:
case SyntaxKind.PropertyAccessExpression:
case SyntaxKind.ElementAccessExpression:
case SyntaxKind.CallExpression:
case SyntaxKind.NewExpression:
case SyntaxKind.TaggedTemplateExpression:
case SyntaxKind.TypeAssertionExpression:
case SyntaxKind.ParenthesizedExpression:
case SyntaxKind.TypeOfExpression:
case SyntaxKind.VoidExpression:
case SyntaxKind.DeleteExpression:
case SyntaxKind.PrefixUnaryExpression:
case SyntaxKind.PostfixUnaryExpression:
case SyntaxKind.BinaryExpression:
case SyntaxKind.ConditionalExpression:
case SyntaxKind.Block:
case SyntaxKind.FunctionBlock:
case SyntaxKind.ModuleBlock:
case SyntaxKind.VariableStatement:
case SyntaxKind.ExpressionStatement:
case SyntaxKind.IfStatement:
case SyntaxKind.DoStatement:
case SyntaxKind.WhileStatement:
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
case SyntaxKind.ContinueStatement:
case SyntaxKind.BreakStatement:
case SyntaxKind.ReturnStatement:
case SyntaxKind.SwitchStatement:
case SyntaxKind.CaseClause:
case SyntaxKind.DefaultClause:
case SyntaxKind.LabeledStatement:
case SyntaxKind.ThrowStatement:
case SyntaxKind.TryStatement:
case SyntaxKind.TryBlock:
case SyntaxKind.CatchBlock:
case SyntaxKind.FinallyBlock:
case SyntaxKind.VariableDeclaration:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.EnumMember:
case SyntaxKind.SourceFile:
forEachChild(node, checkFunctionExpressionBodies);
break;
}
}
function checkBody(node: Block) {
checkBlock(node);
checkFunctionExpressionBodies(node);
}
// Fully type check a source file and collect the relevant diagnostics.
function checkSourceFile(node: SourceFile) {
var links = getNodeLinks(node);
if (!(links.flags & NodeCheckFlags.TypeChecked)) {
emitExtends = false;
potentialThisCollisions.length = 0;
forEach(node.statements, checkSourceElement);
checkFunctionExpressionBodies(node);
if (isExternalModule(node)) {
var symbol = getExportAssignmentSymbol(node.symbol);
if (symbol && symbol.flags & SymbolFlags.Import) {
// Mark the import as referenced so that we emit it in the final .js file.
getSymbolLinks(symbol).referenced = true;
}
}
if (potentialThisCollisions.length) {
forEach(potentialThisCollisions, checkIfThisIsCapturedInEnclosingScope);
potentialThisCollisions.length = 0;
}
if (emitExtends) {
links.flags |= NodeCheckFlags.EmitExtends;
}
links.flags |= NodeCheckFlags.TypeChecked;
}
}
function checkProgram() {
forEach(program.getSourceFiles(), checkSourceFile);
}
function getSortedDiagnostics(): Diagnostic[]{
Debug.assert(fullTypeCheck, "diagnostics are available only in the full typecheck mode");
if (diagnosticsModified) {
diagnostics.sort(compareDiagnostics);
diagnostics = deduplicateSortedDiagnostics(diagnostics);
diagnosticsModified = false;
}
return diagnostics;
}
function getDiagnostics(sourceFile?: SourceFile): Diagnostic[]{
if (sourceFile) {
checkSourceFile(sourceFile);
return filter(getSortedDiagnostics(), d => d.file === sourceFile);
}
checkProgram();
return getSortedDiagnostics();
}
function getDeclarationDiagnostics(targetSourceFile: SourceFile): Diagnostic[] {
var resolver = createResolver();
checkSourceFile(targetSourceFile);
return ts.getDeclarationDiagnostics(program, resolver, targetSourceFile);
}
function getGlobalDiagnostics(): Diagnostic[] {
return filter(getSortedDiagnostics(), d => !d.file);
}
// Language service support
function getNodeAtPosition(sourceFile: SourceFile, position: number): Node {
function findChildAtPosition(parent: Node): Node {
var child = forEachChild(parent, node => {
if (position >= node.pos && position <= node.end && position >= getTokenPosOfNode(node)) {
return findChildAtPosition(node);
}
});
return child || parent;
}
if (position < sourceFile.pos) position = sourceFile.pos;
if (position > sourceFile.end) position = sourceFile.end;
return findChildAtPosition(sourceFile);
}
function isInsideWithStatementBody(node: Node): boolean {
if (node) {
while (node.parent) {
if (node.parent.kind === SyntaxKind.WithStatement && (<WithStatement>node.parent).statement === node) {
return true;
}
node = node.parent;
}
}
return false;
}
function getSymbolsInScope(location: Node, meaning: SymbolFlags): Symbol[]{
var symbols: SymbolTable = {};
var memberFlags: NodeFlags = 0;
function copySymbol(symbol: Symbol, meaning: SymbolFlags) {
if (symbol.flags & meaning) {
var id = symbol.name;
if (!isReservedMemberName(id) && !hasProperty(symbols, id)) {
symbols[id] = symbol;
}
}
}
function copySymbols(source: SymbolTable, meaning: SymbolFlags) {
if (meaning) {
for (var id in source) {
if (hasProperty(source, id)) {
copySymbol(source[id], meaning);
}
}
}
}
if (isInsideWithStatementBody(location)) {
// We cannot answer semantic questions within a with block, do not proceed any further
return [];
}
while (location) {
if (location.locals && !isGlobalSourceFile(location)) {
copySymbols(location.locals, meaning);
}
switch (location.kind) {
case SyntaxKind.SourceFile:
if (!isExternalModule(<SourceFile>location)) break;
case SyntaxKind.ModuleDeclaration:
copySymbols(getSymbolOfNode(location).exports, meaning & SymbolFlags.ModuleMember);
break;
case SyntaxKind.EnumDeclaration:
copySymbols(getSymbolOfNode(location).exports, meaning & SymbolFlags.EnumMember);
break;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
if (!(memberFlags & NodeFlags.Static)) {
copySymbols(getSymbolOfNode(location).members, meaning & SymbolFlags.Type);
}
break;
case SyntaxKind.FunctionExpression:
if ((<FunctionExpression>location).name) {
copySymbol(location.symbol, meaning);
}
break;
case SyntaxKind.CatchBlock:
if ((<CatchBlock>location).variable.text) {
copySymbol(location.symbol, meaning);
}
break;
}
memberFlags = location.flags;
location = location.parent;
}
copySymbols(globals, meaning);
return mapToArray(symbols);
}
function isTypeDeclarationName(name: Node): boolean {
return name.kind == SyntaxKind.Identifier &&
isTypeDeclaration(name.parent) &&
(<Declaration>name.parent).name === name;
}
function isTypeDeclaration(node: Node): boolean {
switch (node.kind) {
case SyntaxKind.TypeParameter:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.TypeAliasDeclaration:
case SyntaxKind.EnumDeclaration:
return true;
}
}
// True if the given identifier is part of a type reference
function isTypeReferenceIdentifier(entityName: EntityName): boolean {
var node: Node = entityName;
while (node.parent && node.parent.kind === SyntaxKind.QualifiedName) node = node.parent;
return node.parent && node.parent.kind === SyntaxKind.TypeReference;
}
function isTypeNode(node: Node): boolean {
if (SyntaxKind.FirstTypeNode <= node.kind && node.kind <= SyntaxKind.LastTypeNode) {
return true;
}
switch (node.kind) {
case SyntaxKind.AnyKeyword:
case SyntaxKind.NumberKeyword:
case SyntaxKind.StringKeyword:
case SyntaxKind.BooleanKeyword:
return true;
case SyntaxKind.VoidKeyword:
return node.parent.kind !== SyntaxKind.VoidExpression;
case SyntaxKind.StringLiteral:
// Specialized signatures can have string literals as their parameters' type names
return node.parent.kind === SyntaxKind.Parameter;
// Identifiers and qualified names may be type nodes, depending on their context. Climb
// above them to find the lowest container
case SyntaxKind.Identifier:
// If the identifier is the RHS of a qualified name, then it's a type iff its parent is.
if (node.parent.kind === SyntaxKind.QualifiedName && (<QualifiedName>node.parent).right === node) {
node = node.parent;
}
// fall through
case SyntaxKind.QualifiedName:
// At this point, node is either a qualified name or an identifier
Debug.assert(node.kind === SyntaxKind.Identifier || node.kind === SyntaxKind.QualifiedName, "'node' was expected to be a qualified name or identifier in 'isTypeNode'.");
var parent = node.parent;
if (parent.kind === SyntaxKind.TypeQuery) {
return false;
}
// Do not recursively call isTypeNode on the parent. In the example:
//
// var a: A.B.C;
//
// Calling isTypeNode would consider the qualified name A.B a type node. Only C or
// A.B.C is a type node.
if (SyntaxKind.FirstTypeNode <= parent.kind && parent.kind <= SyntaxKind.LastTypeNode) {
return true;
}
switch (parent.kind) {
case SyntaxKind.TypeParameter:
return node === (<TypeParameterDeclaration>parent).constraint;
case SyntaxKind.Property:
case SyntaxKind.Parameter:
case SyntaxKind.VariableDeclaration:
return node === (<VariableDeclaration>parent).type;
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.Constructor:
case SyntaxKind.Method:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
return node === (<FunctionLikeDeclaration>parent).type;
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
return node === (<SignatureDeclaration>parent).type;
case SyntaxKind.TypeAssertionExpression:
return node === (<TypeAssertion>parent).type;
case SyntaxKind.CallExpression:
case SyntaxKind.NewExpression:
return (<CallExpression>parent).typeArguments && indexOf((<CallExpression>parent).typeArguments, node) >= 0;
case SyntaxKind.TaggedTemplateExpression:
// TODO (drosen): TaggedTemplateExpressions may eventually support type arguments.
return false;
}
}
return false;
}
function isInRightSideOfImportOrExportAssignment(node: EntityName) {
while (node.parent.kind === SyntaxKind.QualifiedName) {
node = <QualifiedName>node.parent;
}
if (node.parent.kind === SyntaxKind.ImportDeclaration) {
return (<ImportDeclaration>node.parent).moduleReference === node;
}
if (node.parent.kind === SyntaxKind.ExportAssignment) {
return (<ExportAssignment>node.parent).exportName === node;
}
return false;
}
function isRightSideOfQualifiedNameOrPropertyAccess(node: Node) {
return (node.parent.kind === SyntaxKind.QualifiedName && (<QualifiedName>node.parent).right === node) ||
(node.parent.kind === SyntaxKind.PropertyAccessExpression && (<PropertyAccessExpression>node.parent).name === node);
}
function getSymbolOfEntityNameOrPropertyAccessExpression(entityName: EntityName | PropertyAccessExpression): Symbol {
if (isDeclarationOrFunctionExpressionOrCatchVariableName(entityName)) {
return getSymbolOfNode(entityName.parent);
}
if (entityName.parent.kind === SyntaxKind.ExportAssignment) {
return resolveEntityName(/*location*/ entityName.parent.parent, <Identifier>entityName,
/*all meanings*/ SymbolFlags.Value | SymbolFlags.Type | SymbolFlags.Namespace | SymbolFlags.Import);
}
if (entityName.kind !== SyntaxKind.PropertyAccessExpression) {
if (isInRightSideOfImportOrExportAssignment(<EntityName>entityName)) {
// Since we already checked for ExportAssignment, this really could only be an Import
return getSymbolOfPartOfRightHandSideOfImport(<EntityName>entityName);
}
}
if (isRightSideOfQualifiedNameOrPropertyAccess(entityName)) {
entityName = <QualifiedName | PropertyAccessExpression>entityName.parent;
}
if (isExpression(entityName)) {
if (getFullWidth(entityName) === 0) {
// Missing entity name.
return undefined;
}
if (entityName.kind === SyntaxKind.Identifier) {
// Include Import in the meaning, this ensures that we do not follow aliases to where they point and instead
// return the alias symbol.
var meaning: SymbolFlags = SymbolFlags.Value | SymbolFlags.Import;
return resolveEntityName(entityName, <Identifier>entityName, meaning);
}
else if (entityName.kind === SyntaxKind.PropertyAccessExpression) {
var symbol = getNodeLinks(entityName).resolvedSymbol;
if (!symbol) {
checkPropertyAccessExpression(<PropertyAccessExpression>entityName);
}
return getNodeLinks(entityName).resolvedSymbol;
}
else if (entityName.kind === SyntaxKind.QualifiedName) {
var symbol = getNodeLinks(entityName).resolvedSymbol;
if (!symbol) {
checkQualifiedName(<QualifiedName>entityName);
}
return getNodeLinks(entityName).resolvedSymbol;
}
}
else if (isTypeReferenceIdentifier(<EntityName>entityName)) {
var meaning = entityName.parent.kind === SyntaxKind.TypeReference ? SymbolFlags.Type : SymbolFlags.Namespace;
// Include Import in the meaning, this ensures that we do not follow aliases to where they point and instead
// return the alias symbol.
meaning |= SymbolFlags.Import;
return resolveEntityName(entityName, <EntityName>entityName, meaning);
}
// Do we want to return undefined here?
return undefined;
}
function getSymbolInfo(node: Node) {
if (isInsideWithStatementBody(node)) {
// We cannot answer semantic questions within a with block, do not proceed any further
return undefined;
}
if (isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
// This is a declaration, call getSymbolOfNode
return getSymbolOfNode(node.parent);
}
if (node.kind === SyntaxKind.Identifier && isInRightSideOfImportOrExportAssignment(<Identifier>node)) {
return node.parent.kind === SyntaxKind.ExportAssignment
? getSymbolOfEntityNameOrPropertyAccessExpression(<Identifier>node)
: getSymbolOfPartOfRightHandSideOfImport(<Identifier>node);
}
switch (node.kind) {
case SyntaxKind.Identifier:
case SyntaxKind.PropertyAccessExpression:
case SyntaxKind.QualifiedName:
return getSymbolOfEntityNameOrPropertyAccessExpression(<EntityName | PropertyAccessExpression>node);
case SyntaxKind.ThisKeyword:
case SyntaxKind.SuperKeyword:
var type = checkExpression(<Expression>node);
return type.symbol;
case SyntaxKind.ConstructorKeyword:
// constructor keyword for an overload, should take us to the definition if it exist
var constructorDeclaration = node.parent;
if (constructorDeclaration && constructorDeclaration.kind === SyntaxKind.Constructor) {
return (<ClassDeclaration>constructorDeclaration.parent).symbol;
}
return undefined;
case SyntaxKind.StringLiteral:
// External module name in an import declaration
if (isExternalModuleImportDeclaration(node.parent.parent) &&
getExternalModuleImportDeclarationExpression(node.parent.parent) === node) {
var importSymbol = getSymbolOfNode(node.parent.parent);
var moduleType = getTypeOfSymbol(importSymbol);
return moduleType ? moduleType.symbol : undefined;
}
// Intentional fall-through
case SyntaxKind.NumericLiteral:
// index access
if (node.parent.kind == SyntaxKind.ElementAccessExpression && (<ElementAccessExpression>node.parent).argumentExpression === node) {
var objectType = checkExpression((<ElementAccessExpression>node.parent).expression);
if (objectType === unknownType) return undefined;
var apparentType = getApparentType(objectType);
if (apparentType === unknownType) return undefined;
return getPropertyOfType(apparentType, (<LiteralExpression>node).text);
}
break;
}
return undefined;
}
function getShorthandAssignmentValueSymbol(location: Node): Symbol {
// The function returns a value symbol of an identifier in the short-hand property assignment.
// This is necessary as an identifier in short-hand property assignment can contains two meaning:
// property name and property value.
if (location && location.kind === SyntaxKind.ShorthandPropertyAssignment) {
return resolveEntityName(location, (<ShortHandPropertyDeclaration>location).name, SymbolFlags.Value);
}
return undefined;
}
function getTypeOfNode(node: Node): Type {
if (isInsideWithStatementBody(node)) {
// We cannot answer semantic questions within a with block, do not proceed any further
return unknownType;
}
if (isExpression(node)) {
return getTypeOfExpression(<Expression>node);
}
if (isTypeNode(node)) {
return getTypeFromTypeNode(<TypeNode>node);
}
if (isTypeDeclaration(node)) {
// In this case, we call getSymbolOfNode instead of getSymbolInfo because it is a declaration
var symbol = getSymbolOfNode(node);
return getDeclaredTypeOfSymbol(symbol);
}
if (isTypeDeclarationName(node)) {
var symbol = getSymbolInfo(node);
return symbol && getDeclaredTypeOfSymbol(symbol);
}
if (isDeclaration(node)) {
// In this case, we call getSymbolOfNode instead of getSymbolInfo because it is a declaration
var symbol = getSymbolOfNode(node);
return getTypeOfSymbol(symbol);
}
if (isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
var symbol = getSymbolInfo(node);
return symbol && getTypeOfSymbol(symbol);
}
if (isInRightSideOfImportOrExportAssignment(<Identifier>node)) {
var symbol = getSymbolInfo(node);
var declaredType = symbol && getDeclaredTypeOfSymbol(symbol);
return declaredType !== unknownType ? declaredType : getTypeOfSymbol(symbol);
}
return unknownType;
}
function getTypeOfExpression(expr: Expression): Type {
if (isRightSideOfQualifiedNameOrPropertyAccess(expr)) {
expr = <Expression>expr.parent;
}
return checkExpression(expr);
}
// Return the list of properties of the given type, augmented with properties from Function
// if the type has call or construct signatures
function getAugmentedPropertiesOfType(type: Type): Symbol[] {
var type = getApparentType(type);
var propsByName = createSymbolTable(getPropertiesOfType(type));
if (getSignaturesOfType(type, SignatureKind.Call).length || getSignaturesOfType(type, SignatureKind.Construct).length) {
forEach(getPropertiesOfType(globalFunctionType), p => {
if (!hasProperty(propsByName, p.name)) {
propsByName[p.name] = p;
}
});
}
return getNamedMembers(propsByName);
}
function getRootSymbols(symbol: Symbol): Symbol[]{
if (symbol.flags & SymbolFlags.UnionProperty) {
var symbols: Symbol[] = [];
var name = symbol.name;
forEach(getSymbolLinks(symbol).unionType.types, t => {
symbols.push(getPropertyOfType(t, name));
});
return symbols;
}
else if (symbol.flags & SymbolFlags.Transient) {
var target = getSymbolLinks(symbol).target;
if (target) {
return [target];
}
}
return [symbol];
}
// Emitter support
function isExternalModuleSymbol(symbol: Symbol): boolean {
return symbol.flags & SymbolFlags.ValueModule && symbol.declarations.length === 1 && symbol.declarations[0].kind === SyntaxKind.SourceFile;
}
function isNodeDescendentOf(node: Node, ancestor: Node): boolean {
while (node) {
if (node === ancestor) return true;
node = node.parent;
}
return false;
}
function isUniqueLocalName(name: string, container: Node): boolean {
for (var node = container; isNodeDescendentOf(node, container); node = node.nextContainer) {
if (node.locals && hasProperty(node.locals, name) && node.locals[name].flags & (SymbolFlags.Value | SymbolFlags.ExportValue)) {
return false;
}
}
return true;
}
function getLocalNameOfContainer(container: ModuleDeclaration | EnumDeclaration): string {
var links = getNodeLinks(container);
if (!links.localModuleName) {
var prefix = "";
var name = unescapeIdentifier(container.name.text);
while (!isUniqueLocalName(escapeIdentifier(prefix + name), container)) {
prefix += "_";
}
links.localModuleName = prefix + getTextOfNode(container.name);
}
return links.localModuleName;
}
function getLocalNameForSymbol(symbol: Symbol, location: Node): string {
var node = location;
while (node) {
if ((node.kind === SyntaxKind.ModuleDeclaration || node.kind === SyntaxKind.EnumDeclaration) && getSymbolOfNode(node) === symbol) {
return getLocalNameOfContainer(<ModuleDeclaration | EnumDeclaration>node);
}
node = node.parent;
}
Debug.fail("getLocalNameForSymbol failed");
}
function getExpressionNamePrefix(node: Identifier): string {
var symbol = getNodeLinks(node).resolvedSymbol;
if (symbol) {
// In general, we need to prefix an identifier with its parent name if it references
// an exported entity from another module declaration. If we reference an exported
// entity within the same module declaration, then whether we prefix depends on the
// kind of entity. SymbolFlags.ExportHasLocal encompasses all the kinds that we
// do NOT prefix.
var exportSymbol = getExportSymbolOfValueSymbolIfExported(symbol);
if (symbol !== exportSymbol && !(exportSymbol.flags & SymbolFlags.ExportHasLocal)) {
symbol = exportSymbol;
}
if (symbol.parent) {
return isExternalModuleSymbol(symbol.parent) ? "exports" : getLocalNameForSymbol(getParentOfSymbol(symbol), node.parent);
}
}
}
function getExportAssignmentName(node: SourceFile): string {
var symbol = getExportAssignmentSymbol(getSymbolOfNode(node));
return symbol && symbolIsValue(symbol) && !isConstEnumSymbol(symbol) ? symbolToString(symbol): undefined;
}
function isTopLevelValueImportWithEntityName(node: ImportDeclaration): boolean {
if (node.parent.kind !== SyntaxKind.SourceFile || !isInternalModuleImportDeclaration(node)) {
// parent is not source file or it is not reference to internal module
return false;
}
return isImportResolvedToValue(getSymbolOfNode(node));
}
function hasSemanticErrors() {
// Return true if there is any semantic error in a file or globally
return getDiagnostics().length > 0 || getGlobalDiagnostics().length > 0;
}
function isEmitBlocked(sourceFile?: SourceFile): boolean {
return program.getDiagnostics(sourceFile).length !== 0 ||
hasEarlyErrors(sourceFile) ||
(compilerOptions.noEmitOnError && getDiagnostics(sourceFile).length !== 0);
}
function hasEarlyErrors(sourceFile?: SourceFile): boolean {
return forEach(getDiagnostics(sourceFile), d => d.isEarly);
}
function isImportResolvedToValue(symbol: Symbol): boolean {
var target = resolveImport(symbol);
// const enums and modules that contain only const enums are not considered values from the emit perespective
return target !== unknownSymbol && target.flags & SymbolFlags.Value && !isConstEnumOrConstEnumOnlyModule(target);
}
function isConstEnumOrConstEnumOnlyModule(s: Symbol): boolean {
return isConstEnumSymbol(s) || s.constEnumOnlyModule;
}
function isReferencedImportDeclaration(node: ImportDeclaration): boolean {
var symbol = getSymbolOfNode(node);
if (getSymbolLinks(symbol).referenced) {
return true;
}
// logic below will answer 'true' for exported import declaration in a nested module that itself is not exported.
// As a consequence this might cause emitting extra.
if (node.flags & NodeFlags.Export) {
return isImportResolvedToValue(symbol);
}
return false;
}
function isImplementationOfOverload(node: FunctionLikeDeclaration) {
if (node.body) {
var symbol = getSymbolOfNode(node);
var signaturesOfSymbol = getSignaturesOfSymbol(symbol);
// If this function body corresponds to function with multiple signature, it is implementation of overload
// e.g.: function foo(a: string): string;
// function foo(a: number): number;
// function foo(a: any) { // This is implementation of the overloads
// return a;
// }
return signaturesOfSymbol.length > 1 ||
// If there is single signature for the symbol, it is overload if that signature isn't coming from the node
// e.g.: function foo(a: string): string;
// function foo(a: any) { // This is implementation of the overloads
// return a;
// }
(signaturesOfSymbol.length === 1 && signaturesOfSymbol[0].declaration !== node);
}
return false;
}
function getNodeCheckFlags(node: Node): NodeCheckFlags {
return getNodeLinks(node).flags;
}
function getEnumMemberValue(node: EnumMember): number {
computeEnumMemberValues(<EnumDeclaration>node.parent);
return getNodeLinks(node).enumMemberValue;
}
function getConstantValue(node: PropertyAccessExpression | ElementAccessExpression): number {
var symbol = getNodeLinks(node).resolvedSymbol;
if (symbol && (symbol.flags & SymbolFlags.EnumMember)) {
var declaration = symbol.valueDeclaration;
var constantValue: number;
if (declaration.kind === SyntaxKind.EnumMember && (constantValue = getNodeLinks(declaration).enumMemberValue) !== undefined) {
return constantValue;
}
}
return undefined;
}
function writeTypeOfDeclaration(declaration: AccessorDeclaration | VariableOrParameterDeclaration, enclosingDeclaration: Node, flags: TypeFormatFlags, writer: SymbolWriter) {
// Get type of the symbol if this is the valid symbol otherwise get type at location
var symbol = getSymbolOfNode(declaration);
var type = symbol && !(symbol.flags & (SymbolFlags.TypeLiteral | SymbolFlags.CallSignature | SymbolFlags.ConstructSignature))
? getTypeOfSymbol(symbol)
: unknownType;
getSymbolDisplayBuilder().buildTypeDisplay(type, writer, enclosingDeclaration, flags);
}
function writeReturnTypeOfSignatureDeclaration(signatureDeclaration: SignatureDeclaration, enclosingDeclaration: Node, flags: TypeFormatFlags, writer: SymbolWriter) {
var signature = getSignatureFromDeclaration(signatureDeclaration);
getSymbolDisplayBuilder().buildTypeDisplay(getReturnTypeOfSignature(signature), writer, enclosingDeclaration, flags);
}
function createResolver(): EmitResolver {
return {
getProgram: () => program,
getLocalNameOfContainer,
getExpressionNamePrefix,
getExportAssignmentName,
isReferencedImportDeclaration,
getNodeCheckFlags,
getEnumMemberValue,
isTopLevelValueImportWithEntityName,
hasSemanticErrors,
isEmitBlocked,
isDeclarationVisible,
isImplementationOfOverload,
writeTypeOfDeclaration,
writeReturnTypeOfSignatureDeclaration,
isSymbolAccessible,
isEntityNameVisible,
getConstantValue,
};
}
function invokeEmitter(targetSourceFile?: SourceFile) {
var resolver = createResolver();
checkProgram();
return emitFiles(resolver, targetSourceFile);
}
function initializeTypeChecker() {
// Bind all source files and propagate errors
forEach(program.getSourceFiles(), file => {
bindSourceFile(file);
forEach(file.semanticDiagnostics, addDiagnostic);
});
// Initialize global symbol table
forEach(program.getSourceFiles(), file => {
if (!isExternalModule(file)) {
extendSymbolTable(globals, file.locals);
}
});
// Initialize special symbols
getSymbolLinks(undefinedSymbol).type = undefinedType;
getSymbolLinks(argumentsSymbol).type = getGlobalType("IArguments");
getSymbolLinks(unknownSymbol).type = unknownType;
globals[undefinedSymbol.name] = undefinedSymbol;
// Initialize special types
globalArraySymbol = getGlobalSymbol("Array");
globalArrayType = getTypeOfGlobalSymbol(globalArraySymbol, 1);
globalObjectType = getGlobalType("Object");
globalFunctionType = getGlobalType("Function");
globalStringType = getGlobalType("String");
globalNumberType = getGlobalType("Number");
globalBooleanType = getGlobalType("Boolean");
globalRegExpType = getGlobalType("RegExp");
// If we're in ES6 mode, load the TemplateStringsArray.
// Otherwise, default to 'unknown' for the purposes of type checking in LS scenarios.
globalTemplateStringsArrayType = compilerOptions.target >= ScriptTarget.ES6
? getGlobalType("TemplateStringsArray")
: unknownType;
}
initializeTypeChecker();
return checker;
}
}