TypeScript/src/compiler/binder.ts
2016-04-18 13:27:33 -07:00

2465 lines
121 KiB
TypeScript

/// <reference path="utilities.ts"/>
/// <reference path="parser.ts"/>
/* @internal */
namespace ts {
export let bindTime = 0;
export const enum ModuleInstanceState {
NonInstantiated = 0,
Instantiated = 1,
ConstEnumOnly = 2
}
const enum Reachability {
Uninitialized = 1 << 0,
Reachable = 1 << 1,
Unreachable = 1 << 2,
ReportedUnreachable = 1 << 3
}
function or(state1: Reachability, state2: Reachability): Reachability {
return (state1 | state2) & Reachability.Reachable
? Reachability.Reachable
: (state1 & state2) & Reachability.ReportedUnreachable
? Reachability.ReportedUnreachable
: Reachability.Unreachable;
}
export function getModuleInstanceState(node: Node): ModuleInstanceState {
// A module is uninstantiated if it contains only
// 1. interface declarations, type alias declarations
if (node.kind === SyntaxKind.InterfaceDeclaration || node.kind === SyntaxKind.TypeAliasDeclaration) {
return ModuleInstanceState.NonInstantiated;
}
// 2. const enum declarations
else if (isConstEnumDeclaration(node)) {
return ModuleInstanceState.ConstEnumOnly;
}
// 3. non-exported import declarations
else if ((node.kind === SyntaxKind.ImportDeclaration || node.kind === SyntaxKind.ImportEqualsDeclaration) && !(hasModifier(node, ModifierFlags.Export))) {
return ModuleInstanceState.NonInstantiated;
}
// 4. other uninstantiated module declarations.
else if (node.kind === SyntaxKind.ModuleBlock) {
let state = ModuleInstanceState.NonInstantiated;
forEachChild(node, n => {
switch (getModuleInstanceState(n)) {
case ModuleInstanceState.NonInstantiated:
// child is non-instantiated - continue searching
return false;
case ModuleInstanceState.ConstEnumOnly:
// child is const enum only - record state and continue searching
state = ModuleInstanceState.ConstEnumOnly;
return false;
case ModuleInstanceState.Instantiated:
// child is instantiated - record state and stop
state = ModuleInstanceState.Instantiated;
return true;
}
});
return state;
}
else if (node.kind === SyntaxKind.ModuleDeclaration) {
return getModuleInstanceState((<ModuleDeclaration>node).body);
}
else {
return ModuleInstanceState.Instantiated;
}
}
const enum ContainerFlags {
// The current node is not a container, and no container manipulation should happen before
// recursing into it.
None = 0,
// The current node is a container. It should be set as the current container (and block-
// container) before recursing into it. The current node does not have locals. Examples:
//
// Classes, ObjectLiterals, TypeLiterals, Interfaces...
IsContainer = 1 << 0,
// The current node is a block-scoped-container. It should be set as the current block-
// container before recursing into it. Examples:
//
// Blocks (when not parented by functions), Catch clauses, For/For-in/For-of statements...
IsBlockScopedContainer = 1 << 1,
HasLocals = 1 << 2,
// If the current node is a container that also container that also contains locals. Examples:
//
// Functions, Methods, Modules, Source-files.
IsContainerWithLocals = IsContainer | HasLocals
}
const binder = createBinder();
export function bindSourceFile(file: SourceFile, options: CompilerOptions) {
const start = new Date().getTime();
binder(file, options);
bindTime += new Date().getTime() - start;
}
function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
let file: SourceFile;
let options: CompilerOptions;
let languageVersion: ScriptTarget;
let parent: Node;
let container: Node;
let blockScopeContainer: Node;
let lastContainer: Node;
let seenThisKeyword: boolean;
// state used by reachability checks
let hasExplicitReturn: boolean;
let currentReachabilityState: Reachability;
let labelStack: Reachability[];
let labelIndexMap: Map<number>;
let implicitLabels: number[];
// state used for emit helpers
let hasClassExtends: boolean;
let hasAsyncFunctions: boolean;
let hasDecorators: boolean;
let hasParameterDecorators: boolean;
let hasJsxSpreadAttribute: boolean;
// If this file is an external module, then it is automatically in strict-mode according to
// ES6. If it is not an external module, then we'll determine if it is in strict mode or
// not depending on if we see "use strict" in certain places (or if we hit a class/namespace).
let inStrictMode: boolean;
let symbolCount = 0;
let Symbol: { new (flags: SymbolFlags, name: string): Symbol };
let classifiableNames: Map<string>;
// state used to aggregate transform flags during bind.
let subtreeTransformFlags: TransformFlags = TransformFlags.None;
let skipTransformFlagAggregation: boolean;
function bindSourceFile(f: SourceFile, opts: CompilerOptions) {
file = f;
options = opts;
languageVersion = getEmitScriptTarget(options);
inStrictMode = !!file.externalModuleIndicator;
classifiableNames = {};
skipTransformFlagAggregation = isDeclarationFile(file);
Symbol = objectAllocator.getSymbolConstructor();
if (!file.locals) {
bind(file);
file.symbolCount = symbolCount;
file.classifiableNames = classifiableNames;
}
file = undefined;
options = undefined;
languageVersion = undefined;
parent = undefined;
container = undefined;
blockScopeContainer = undefined;
lastContainer = undefined;
seenThisKeyword = false;
hasExplicitReturn = false;
labelStack = undefined;
labelIndexMap = undefined;
implicitLabels = undefined;
hasClassExtends = false;
hasAsyncFunctions = false;
hasDecorators = false;
hasParameterDecorators = false;
subtreeTransformFlags = TransformFlags.None;
hasJsxSpreadAttribute = false;
}
return bindSourceFile;
function createSymbol(flags: SymbolFlags, name: string): Symbol {
symbolCount++;
return new Symbol(flags, name);
}
function addDeclarationToSymbol(symbol: Symbol, node: Declaration, symbolFlags: SymbolFlags) {
symbol.flags |= symbolFlags;
node.symbol = symbol;
if (!symbol.declarations) {
symbol.declarations = [];
}
symbol.declarations.push(node);
if (symbolFlags & SymbolFlags.HasExports && !symbol.exports) {
symbol.exports = {};
}
if (symbolFlags & SymbolFlags.HasMembers && !symbol.members) {
symbol.members = {};
}
if (symbolFlags & SymbolFlags.Value) {
const valueDeclaration = symbol.valueDeclaration;
if (!valueDeclaration ||
(valueDeclaration.kind !== node.kind && valueDeclaration.kind === SyntaxKind.ModuleDeclaration)) {
// other kinds of value declarations take precedence over modules
symbol.valueDeclaration = node;
}
}
}
// Should not be called on a declaration with a computed property name,
// unless it is a well known Symbol.
function getDeclarationName(node: Declaration): string {
if (node.name) {
if (isAmbientModule(node)) {
return isGlobalScopeAugmentation(<ModuleDeclaration>node) ? "__global" : `"${(<LiteralExpression>node.name).text}"`;
}
if (node.name.kind === SyntaxKind.ComputedPropertyName) {
const nameExpression = (<ComputedPropertyName>node.name).expression;
// treat computed property names where expression is string/numeric literal as just string/numeric literal
if (isStringOrNumericLiteral(nameExpression.kind)) {
return (<LiteralExpression>nameExpression).text;
}
Debug.assert(isWellKnownSymbolSyntactically(nameExpression));
return getPropertyNameForKnownSymbolName((<PropertyAccessExpression>nameExpression).name.text);
}
return (<Identifier | LiteralExpression>node.name).text;
}
switch (node.kind) {
case SyntaxKind.Constructor:
return "__constructor";
case SyntaxKind.FunctionType:
case SyntaxKind.CallSignature:
return "__call";
case SyntaxKind.ConstructorType:
case SyntaxKind.ConstructSignature:
return "__new";
case SyntaxKind.IndexSignature:
return "__index";
case SyntaxKind.ExportDeclaration:
return "__export";
case SyntaxKind.ExportAssignment:
return (<ExportAssignment>node).isExportEquals ? "export=" : "default";
case SyntaxKind.BinaryExpression:
switch (getSpecialPropertyAssignmentKind(node)) {
case SpecialPropertyAssignmentKind.ModuleExports:
// module.exports = ...
return "export=";
case SpecialPropertyAssignmentKind.ExportsProperty:
case SpecialPropertyAssignmentKind.ThisProperty:
// exports.x = ... or this.y = ...
return ((node as BinaryExpression).left as PropertyAccessExpression).name.text;
case SpecialPropertyAssignmentKind.PrototypeProperty:
// className.prototype.methodName = ...
return (((node as BinaryExpression).left as PropertyAccessExpression).expression as PropertyAccessExpression).name.text;
}
Debug.fail("Unknown binary declaration kind");
break;
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.ClassDeclaration:
return hasModifier(node, ModifierFlags.Default) ? "default" : undefined;
case SyntaxKind.JSDocFunctionType:
return isJSDocConstructSignature(node) ? "__new" : "__call";
case SyntaxKind.Parameter:
// Parameters with names are handled at the top of this function. Parameters
// without names can only come from JSDocFunctionTypes.
Debug.assert(node.parent.kind === SyntaxKind.JSDocFunctionType);
let functionType = <JSDocFunctionType>node.parent;
let index = indexOf(functionType.parameters, node);
return "p" + index;
}
}
function getDisplayName(node: Declaration): string {
return node.name ? declarationNameToString(node.name) : getDeclarationName(node);
}
/**
* Declares a Symbol for the node and adds it to symbols. Reports errors for conflicting identifier names.
* @param symbolTable - The symbol table which node will be added to.
* @param parent - node's parent declaration.
* @param node - The declaration to be added to the symbol table
* @param includes - The SymbolFlags that node has in addition to its declaration type (eg: export, ambient, etc.)
* @param excludes - The flags which node cannot be declared alongside in a symbol table. Used to report forbidden declarations.
*/
function declareSymbol(symbolTable: SymbolTable, parent: Symbol, node: Declaration, includes: SymbolFlags, excludes: SymbolFlags): Symbol {
Debug.assert(!hasDynamicName(node));
const isDefaultExport = hasModifier(node, ModifierFlags.Default);
// The exported symbol for an export default function/class node is always named "default"
const name = isDefaultExport && parent ? "default" : getDeclarationName(node);
let symbol: Symbol;
if (name !== undefined) {
// Check and see if the symbol table already has a symbol with this name. If not,
// create a new symbol with this name and add it to the table. Note that we don't
// give the new symbol any flags *yet*. This ensures that it will not conflict
// with the 'excludes' flags we pass in.
//
// If we do get an existing symbol, see if it conflicts with the new symbol we're
// creating. For example, a 'var' symbol and a 'class' symbol will conflict within
// the same symbol table. If we have a conflict, report the issue on each
// declaration we have for this symbol, and then create a new symbol for this
// declaration.
//
// If we created a new symbol, either because we didn't have a symbol with this name
// in the symbol table, or we conflicted with an existing symbol, then just add this
// node as the sole declaration of the new symbol.
//
// Otherwise, we'll be merging into a compatible existing symbol (for example when
// you have multiple 'vars' with the same name in the same container). In this case
// just add this node into the declarations list of the symbol.
symbol = hasProperty(symbolTable, name)
? symbolTable[name]
: (symbolTable[name] = createSymbol(SymbolFlags.None, name));
if (name && (includes & SymbolFlags.Classifiable)) {
classifiableNames[name] = name;
}
if (symbol.flags & excludes) {
if (node.name) {
node.name.parent = node;
}
// Report errors every position with duplicate declaration
// Report errors on previous encountered declarations
let message = symbol.flags & SymbolFlags.BlockScopedVariable
? Diagnostics.Cannot_redeclare_block_scoped_variable_0
: Diagnostics.Duplicate_identifier_0;
forEach(symbol.declarations, declaration => {
if (hasModifier(declaration, ModifierFlags.Default)) {
message = Diagnostics.A_module_cannot_have_multiple_default_exports;
}
});
forEach(symbol.declarations, declaration => {
file.bindDiagnostics.push(createDiagnosticForNode(declaration.name || declaration, message, getDisplayName(declaration)));
});
file.bindDiagnostics.push(createDiagnosticForNode(node.name || node, message, getDisplayName(node)));
symbol = createSymbol(SymbolFlags.None, name);
}
}
else {
symbol = createSymbol(SymbolFlags.None, "__missing");
}
addDeclarationToSymbol(symbol, node, includes);
symbol.parent = parent;
return symbol;
}
function declareModuleMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): Symbol {
const hasExportModifier = getCombinedModifierFlags(node) & ModifierFlags.Export;
if (symbolFlags & SymbolFlags.Alias) {
if (node.kind === SyntaxKind.ExportSpecifier || (node.kind === SyntaxKind.ImportEqualsDeclaration && hasExportModifier)) {
return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
}
else {
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
else {
// Exported module members are given 2 symbols: A local symbol that is classified with an ExportValue,
// ExportType, or ExportContainer flag, and an associated export symbol with all the correct flags set
// on it. There are 2 main reasons:
//
// 1. We treat locals and exports of the same name as mutually exclusive within a container.
// That means the binder will issue a Duplicate Identifier error if you mix locals and exports
// with the same name in the same container.
// TODO: Make this a more specific error and decouple it from the exclusion logic.
// 2. When we checkIdentifier in the checker, we set its resolved symbol to the local symbol,
// but return the export symbol (by calling getExportSymbolOfValueSymbolIfExported). That way
// when the emitter comes back to it, it knows not to qualify the name if it was found in a containing scope.
// NOTE: Nested ambient modules always should go to to 'locals' table to prevent their automatic merge
// during global merging in the checker. Why? The only case when ambient module is permitted inside another module is module augmentation
// and this case is specially handled. Module augmentations should only be merged with original module definition
// and should never be merged directly with other augmentation, and the latter case would be possible if automatic merge is allowed.
if (!isAmbientModule(node) && (hasExportModifier || container.flags & NodeFlags.ExportContext)) {
const exportKind =
(symbolFlags & SymbolFlags.Value ? SymbolFlags.ExportValue : 0) |
(symbolFlags & SymbolFlags.Type ? SymbolFlags.ExportType : 0) |
(symbolFlags & SymbolFlags.Namespace ? SymbolFlags.ExportNamespace : 0);
const local = declareSymbol(container.locals, undefined, node, exportKind, symbolExcludes);
local.exportSymbol = declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
node.localSymbol = local;
return local;
}
else {
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
}
// All container nodes are kept on a linked list in declaration order. This list is used by
// the getLocalNameOfContainer function in the type checker to validate that the local name
// used for a container is unique.
function bindChildren(node: Node) {
// Before we recurse into a node's children, we first save the existing parent, container
// and block-container. Then after we pop out of processing the children, we restore
// these saved values.
const saveParent = parent;
const saveContainer = container;
const savedBlockScopeContainer = blockScopeContainer;
// This node will now be set as the parent of all of its children as we recurse into them.
parent = node;
// Depending on what kind of node this is, we may have to adjust the current container
// and block-container. If the current node is a container, then it is automatically
// considered the current block-container as well. Also, for containers that we know
// may contain locals, we proactively initialize the .locals field. We do this because
// it's highly likely that the .locals will be needed to place some child in (for example,
// a parameter, or variable declaration).
//
// However, we do not proactively create the .locals for block-containers because it's
// totally normal and common for block-containers to never actually have a block-scoped
// variable in them. We don't want to end up allocating an object for every 'block' we
// run into when most of them won't be necessary.
//
// Finally, if this is a block-container, then we clear out any existing .locals object
// it may contain within it. This happens in incremental scenarios. Because we can be
// reusing a node from a previous compilation, that node may have had 'locals' created
// for it. We must clear this so we don't accidentally move any stale data forward from
// a previous compilation.
const containerFlags = getContainerFlags(node);
if (containerFlags & ContainerFlags.IsContainer) {
container = blockScopeContainer = node;
if (containerFlags & ContainerFlags.HasLocals) {
container.locals = {};
}
addToContainerChain(container);
}
else if (containerFlags & ContainerFlags.IsBlockScopedContainer) {
blockScopeContainer = node;
blockScopeContainer.locals = undefined;
}
let savedReachabilityState: Reachability;
let savedLabelStack: Reachability[];
let savedLabels: Map<number>;
let savedImplicitLabels: number[];
let savedHasExplicitReturn: boolean;
const kind = node.kind;
let flags = node.flags;
// reset all reachability check related flags on node (for incremental scenarios)
flags &= ~NodeFlags.ReachabilityCheckFlags;
// reset all emit helper flags on node (for incremental scenarios)
flags &= ~NodeFlags.EmitHelperFlags;
if (kind === SyntaxKind.InterfaceDeclaration) {
seenThisKeyword = false;
}
const saveState = kind === SyntaxKind.SourceFile || kind === SyntaxKind.ModuleBlock || isFunctionLikeKind(kind);
if (saveState) {
savedReachabilityState = currentReachabilityState;
savedLabelStack = labelStack;
savedLabels = labelIndexMap;
savedImplicitLabels = implicitLabels;
savedHasExplicitReturn = hasExplicitReturn;
currentReachabilityState = Reachability.Reachable;
hasExplicitReturn = false;
labelStack = labelIndexMap = implicitLabels = undefined;
}
if (isInJavaScriptFile(node) && node.jsDocComment) {
bind(node.jsDocComment);
}
bindReachableStatement(node);
if (currentReachabilityState === Reachability.Reachable && isFunctionLikeKind(kind) && nodeIsPresent((<FunctionLikeDeclaration>node).body)) {
flags |= NodeFlags.HasImplicitReturn;
if (hasExplicitReturn) {
flags |= NodeFlags.HasExplicitReturn;
}
}
if (kind === SyntaxKind.InterfaceDeclaration) {
flags = seenThisKeyword ? flags | NodeFlags.ContainsThis : flags & ~NodeFlags.ContainsThis;
}
if (kind === SyntaxKind.SourceFile) {
if (hasClassExtends) {
flags |= NodeFlags.HasClassExtends;
}
if (hasDecorators) {
flags |= NodeFlags.HasDecorators;
}
if (hasParameterDecorators) {
flags |= NodeFlags.HasParamDecorators;
}
if (hasAsyncFunctions) {
flags |= NodeFlags.HasAsyncFunctions;
}
if (hasJsxSpreadAttribute) {
flags |= NodeFlags.HasJsxSpreadAttribute;
}
}
node.flags = flags;
if (saveState) {
hasExplicitReturn = savedHasExplicitReturn;
currentReachabilityState = savedReachabilityState;
labelStack = savedLabelStack;
labelIndexMap = savedLabels;
implicitLabels = savedImplicitLabels;
}
container = saveContainer;
parent = saveParent;
blockScopeContainer = savedBlockScopeContainer;
}
/**
* Returns true if node and its subnodes were successfully traversed.
* Returning false means that node was not examined and caller needs to dive into the node himself.
*/
function bindReachableStatement(node: Node): void {
if (checkUnreachable(node)) {
forEachChild(node, bind);
return;
}
switch (node.kind) {
case SyntaxKind.WhileStatement:
bindWhileStatement(<WhileStatement>node);
break;
case SyntaxKind.DoStatement:
bindDoStatement(<DoStatement>node);
break;
case SyntaxKind.ForStatement:
bindForStatement(<ForStatement>node);
break;
case SyntaxKind.ForInStatement:
case SyntaxKind.ForOfStatement:
bindForInOrForOfStatement(<ForInStatement | ForOfStatement>node);
break;
case SyntaxKind.IfStatement:
bindIfStatement(<IfStatement>node);
break;
case SyntaxKind.ReturnStatement:
case SyntaxKind.ThrowStatement:
bindReturnOrThrow(<ReturnStatement | ThrowStatement>node);
break;
case SyntaxKind.BreakStatement:
case SyntaxKind.ContinueStatement:
bindBreakOrContinueStatement(<BreakOrContinueStatement>node);
break;
case SyntaxKind.TryStatement:
bindTryStatement(<TryStatement>node);
break;
case SyntaxKind.SwitchStatement:
bindSwitchStatement(<SwitchStatement>node);
break;
case SyntaxKind.CaseBlock:
bindCaseBlock(<CaseBlock>node);
break;
case SyntaxKind.LabeledStatement:
bindLabeledStatement(<LabeledStatement>node);
break;
default:
forEachChild(node, bind);
break;
}
}
function bindWhileStatement(n: WhileStatement): void {
const preWhileState =
n.expression.kind === SyntaxKind.FalseKeyword ? Reachability.Unreachable : currentReachabilityState;
const postWhileState =
n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : currentReachabilityState;
// bind expressions (don't affect reachability)
bind(n.expression);
currentReachabilityState = preWhileState;
const postWhileLabel = pushImplicitLabel();
bind(n.statement);
popImplicitLabel(postWhileLabel, postWhileState);
}
function bindDoStatement(n: DoStatement): void {
const preDoState = currentReachabilityState;
const postDoLabel = pushImplicitLabel();
bind(n.statement);
const postDoState = n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : preDoState;
popImplicitLabel(postDoLabel, postDoState);
// bind expressions (don't affect reachability)
bind(n.expression);
}
function bindForStatement(n: ForStatement): void {
const preForState = currentReachabilityState;
const postForLabel = pushImplicitLabel();
// bind expressions (don't affect reachability)
bind(n.initializer);
bind(n.condition);
bind(n.incrementor);
bind(n.statement);
// for statement is considered infinite when it condition is either omitted or is true keyword
// - for(..;;..)
// - for(..;true;..)
const isInfiniteLoop = (!n.condition || n.condition.kind === SyntaxKind.TrueKeyword);
const postForState = isInfiniteLoop ? Reachability.Unreachable : preForState;
popImplicitLabel(postForLabel, postForState);
}
function bindForInOrForOfStatement(n: ForInStatement | ForOfStatement): void {
const preStatementState = currentReachabilityState;
const postStatementLabel = pushImplicitLabel();
// bind expressions (don't affect reachability)
bind(n.initializer);
bind(n.expression);
bind(n.statement);
popImplicitLabel(postStatementLabel, preStatementState);
}
function bindIfStatement(n: IfStatement): void {
// denotes reachability state when entering 'thenStatement' part of the if statement:
// i.e. if condition is false then thenStatement is unreachable
const ifTrueState = n.expression.kind === SyntaxKind.FalseKeyword ? Reachability.Unreachable : currentReachabilityState;
// denotes reachability state when entering 'elseStatement':
// i.e. if condition is true then elseStatement is unreachable
const ifFalseState = n.expression.kind === SyntaxKind.TrueKeyword ? Reachability.Unreachable : currentReachabilityState;
currentReachabilityState = ifTrueState;
// bind expression (don't affect reachability)
bind(n.expression);
bind(n.thenStatement);
if (n.elseStatement) {
const preElseState = currentReachabilityState;
currentReachabilityState = ifFalseState;
bind(n.elseStatement);
currentReachabilityState = or(currentReachabilityState, preElseState);
}
else {
currentReachabilityState = or(currentReachabilityState, ifFalseState);
}
}
function bindReturnOrThrow(n: ReturnStatement | ThrowStatement): void {
// bind expression (don't affect reachability)
bind(n.expression);
if (n.kind === SyntaxKind.ReturnStatement) {
hasExplicitReturn = true;
}
currentReachabilityState = Reachability.Unreachable;
}
function bindBreakOrContinueStatement(n: BreakOrContinueStatement): void {
// call bind on label (don't affect reachability)
bind(n.label);
// for continue case touch label so it will be marked a used
const isValidJump = jumpToLabel(n.label, n.kind === SyntaxKind.BreakStatement ? currentReachabilityState : Reachability.Unreachable);
if (isValidJump) {
currentReachabilityState = Reachability.Unreachable;
}
}
function bindTryStatement(n: TryStatement): void {
// catch\finally blocks has the same reachability as try block
const preTryState = currentReachabilityState;
bind(n.tryBlock);
const postTryState = currentReachabilityState;
currentReachabilityState = preTryState;
bind(n.catchClause);
const postCatchState = currentReachabilityState;
currentReachabilityState = preTryState;
bind(n.finallyBlock);
// post catch/finally state is reachable if
// - post try state is reachable - control flow can fall out of try block
// - post catch state is reachable - control flow can fall out of catch block
currentReachabilityState = n.catchClause ? or(postTryState, postCatchState) : postTryState;
}
function bindSwitchStatement(n: SwitchStatement): void {
const preSwitchState = currentReachabilityState;
const postSwitchLabel = pushImplicitLabel();
// bind expression (don't affect reachability)
bind(n.expression);
bind(n.caseBlock);
const hasDefault = forEach(n.caseBlock.clauses, c => c.kind === SyntaxKind.DefaultClause);
// post switch state is unreachable if switch is exhaustive (has a default case ) and does not have fallthrough from the last case
const postSwitchState = hasDefault && currentReachabilityState !== Reachability.Reachable ? Reachability.Unreachable : preSwitchState;
popImplicitLabel(postSwitchLabel, postSwitchState);
}
function bindCaseBlock(n: CaseBlock): void {
const startState = currentReachabilityState;
for (let i = 0; i < n.clauses.length; i++) {
const clause = n.clauses[i];
currentReachabilityState = startState;
bind(clause);
if (clause.statements.length &&
i !== n.clauses.length - 1 && // allow fallthrough from the last case
currentReachabilityState === Reachability.Reachable &&
options.noFallthroughCasesInSwitch) {
errorOnFirstToken(clause, Diagnostics.Fallthrough_case_in_switch);
}
}
}
function bindLabeledStatement(n: LabeledStatement): void {
// call bind on label (don't affect reachability)
bind(n.label);
const ok = pushNamedLabel(n.label);
bind(n.statement);
if (ok) {
popNamedLabel(n.label, currentReachabilityState);
}
}
function getContainerFlags(node: Node): ContainerFlags {
switch (node.kind) {
case SyntaxKind.ClassExpression:
case SyntaxKind.ClassDeclaration:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.TypeLiteral:
case SyntaxKind.JSDocRecordType:
return ContainerFlags.IsContainer;
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionType:
case SyntaxKind.JSDocFunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.ModuleDeclaration:
case SyntaxKind.SourceFile:
case SyntaxKind.TypeAliasDeclaration:
return ContainerFlags.IsContainerWithLocals;
case SyntaxKind.CatchClause:
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
case SyntaxKind.ForOfStatement:
case SyntaxKind.CaseBlock:
return ContainerFlags.IsBlockScopedContainer;
case SyntaxKind.Block:
// do not treat blocks directly inside a function as a block-scoped-container.
// Locals that reside in this block should go to the function locals. Otherwise 'x'
// would not appear to be a redeclaration of a block scoped local in the following
// example:
//
// function foo() {
// var x;
// let x;
// }
//
// If we placed 'var x' into the function locals and 'let x' into the locals of
// the block, then there would be no collision.
//
// By not creating a new block-scoped-container here, we ensure that both 'var x'
// and 'let x' go into the Function-container's locals, and we do get a collision
// conflict.
return isFunctionLike(node.parent) ? ContainerFlags.None : ContainerFlags.IsBlockScopedContainer;
}
return ContainerFlags.None;
}
function addToContainerChain(next: Node) {
if (lastContainer) {
lastContainer.nextContainer = next;
}
lastContainer = next;
}
function declareSymbolAndAddToSymbolTable(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): void {
// Just call this directly so that the return type of this function stays "void".
declareSymbolAndAddToSymbolTableWorker(node, symbolFlags, symbolExcludes);
}
function declareSymbolAndAddToSymbolTableWorker(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags): Symbol {
switch (container.kind) {
// Modules, source files, and classes need specialized handling for how their
// members are declared (for example, a member of a class will go into a specific
// symbol table depending on if it is static or not). We defer to specialized
// handlers to take care of declaring these child members.
case SyntaxKind.ModuleDeclaration:
return declareModuleMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.SourceFile:
return declareSourceFileMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.ClassExpression:
case SyntaxKind.ClassDeclaration:
return declareClassMember(node, symbolFlags, symbolExcludes);
case SyntaxKind.EnumDeclaration:
return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
case SyntaxKind.TypeLiteral:
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.JSDocRecordType:
// Interface/Object-types always have their children added to the 'members' of
// their container. They are only accessible through an instance of their
// container, and are never in scope otherwise (even inside the body of the
// object / type / interface declaring them). An exception is type parameters,
// which are in scope without qualification (similar to 'locals').
return declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
case SyntaxKind.Constructor:
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
case SyntaxKind.FunctionDeclaration:
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
case SyntaxKind.JSDocFunctionType:
case SyntaxKind.TypeAliasDeclaration:
// All the children of these container types are never visible through another
// symbol (i.e. through another symbol's 'exports' or 'members'). Instead,
// they're only accessed 'lexically' (i.e. from code that exists underneath
// their container in the tree. To accomplish this, we simply add their declared
// symbol to the 'locals' of the container. These symbols can then be found as
// the type checker walks up the containers, checking them for matching names.
return declareSymbol(container.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
function declareClassMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
return hasModifier(node, ModifierFlags.Static)
? declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes)
: declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
}
function declareSourceFileMember(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
return isExternalModule(file)
? declareModuleMember(node, symbolFlags, symbolExcludes)
: declareSymbol(file.locals, undefined, node, symbolFlags, symbolExcludes);
}
function hasExportDeclarations(node: ModuleDeclaration | SourceFile): boolean {
const body = node.kind === SyntaxKind.SourceFile ? node : (<ModuleDeclaration>node).body;
if (body.kind === SyntaxKind.SourceFile || body.kind === SyntaxKind.ModuleBlock) {
for (const stat of (<Block>body).statements) {
if (stat.kind === SyntaxKind.ExportDeclaration || stat.kind === SyntaxKind.ExportAssignment) {
return true;
}
}
}
return false;
}
function setExportContextFlag(node: ModuleDeclaration | SourceFile) {
// A declaration source file or ambient module declaration that contains no export declarations (but possibly regular
// declarations with export modifiers) is an export context in which declarations are implicitly exported.
if (isInAmbientContext(node) && !hasExportDeclarations(node)) {
node.flags |= NodeFlags.ExportContext;
}
else {
node.flags &= ~NodeFlags.ExportContext;
}
}
function bindModuleDeclaration(node: ModuleDeclaration) {
setExportContextFlag(node);
if (isAmbientModule(node)) {
if (hasModifier(node, ModifierFlags.Export)) {
errorOnFirstToken(node, Diagnostics.export_modifier_cannot_be_applied_to_ambient_modules_and_module_augmentations_since_they_are_always_visible);
}
if (isExternalModuleAugmentation(node)) {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.NamespaceModule, SymbolFlags.NamespaceModuleExcludes);
}
else {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.ValueModule, SymbolFlags.ValueModuleExcludes);
}
}
else {
const state = getModuleInstanceState(node);
if (state === ModuleInstanceState.NonInstantiated) {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.NamespaceModule, SymbolFlags.NamespaceModuleExcludes);
}
else {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.ValueModule, SymbolFlags.ValueModuleExcludes);
if (node.symbol.flags & (SymbolFlags.Function | SymbolFlags.Class | SymbolFlags.RegularEnum)) {
// if module was already merged with some function, class or non-const enum
// treat is a non-const-enum-only
node.symbol.constEnumOnlyModule = false;
}
else {
const currentModuleIsConstEnumOnly = state === ModuleInstanceState.ConstEnumOnly;
if (node.symbol.constEnumOnlyModule === undefined) {
// non-merged case - use the current state
node.symbol.constEnumOnlyModule = currentModuleIsConstEnumOnly;
}
else {
// merged case: module is const enum only if all its pieces are non-instantiated or const enum
node.symbol.constEnumOnlyModule = node.symbol.constEnumOnlyModule && currentModuleIsConstEnumOnly;
}
}
}
}
}
function bindFunctionOrConstructorType(node: SignatureDeclaration): void {
// For a given function symbol "<...>(...) => T" we want to generate a symbol identical
// to the one we would get for: { <...>(...): T }
//
// We do that by making an anonymous type literal symbol, and then setting the function
// symbol as its sole member. To the rest of the system, this symbol will be indistinguishable
// from an actual type literal symbol you would have gotten had you used the long form.
const symbol = createSymbol(SymbolFlags.Signature, getDeclarationName(node));
addDeclarationToSymbol(symbol, node, SymbolFlags.Signature);
const typeLiteralSymbol = createSymbol(SymbolFlags.TypeLiteral, "__type");
addDeclarationToSymbol(typeLiteralSymbol, node, SymbolFlags.TypeLiteral);
typeLiteralSymbol.members = { [symbol.name]: symbol };
}
function bindObjectLiteralExpression(node: ObjectLiteralExpression) {
const enum ElementKind {
Property = 1,
Accessor = 2
}
if (inStrictMode) {
const seen: Map<ElementKind> = {};
for (const prop of node.properties) {
if (prop.name.kind !== SyntaxKind.Identifier) {
continue;
}
const identifier = <Identifier>prop.name;
// ECMA-262 11.1.5 Object Initializer
// If previous is not undefined then throw a SyntaxError exception if any of the following conditions are true
// a.This production is contained in strict code and IsDataDescriptor(previous) is true and
// IsDataDescriptor(propId.descriptor) is true.
// b.IsDataDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true.
// c.IsAccessorDescriptor(previous) is true and IsDataDescriptor(propId.descriptor) is true.
// d.IsAccessorDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true
// and either both previous and propId.descriptor have[[Get]] fields or both previous and propId.descriptor have[[Set]] fields
const currentKind = prop.kind === SyntaxKind.PropertyAssignment || prop.kind === SyntaxKind.ShorthandPropertyAssignment || prop.kind === SyntaxKind.MethodDeclaration
? ElementKind.Property
: ElementKind.Accessor;
const existingKind = seen[identifier.text];
if (!existingKind) {
seen[identifier.text] = currentKind;
continue;
}
if (currentKind === ElementKind.Property && existingKind === ElementKind.Property) {
const span = getErrorSpanForNode(file, identifier);
file.bindDiagnostics.push(createFileDiagnostic(file, span.start, span.length,
Diagnostics.An_object_literal_cannot_have_multiple_properties_with_the_same_name_in_strict_mode));
}
}
}
return bindAnonymousDeclaration(node, SymbolFlags.ObjectLiteral, "__object");
}
function bindAnonymousDeclaration(node: Declaration, symbolFlags: SymbolFlags, name: string) {
const symbol = createSymbol(symbolFlags, name);
addDeclarationToSymbol(symbol, node, symbolFlags);
}
function bindBlockScopedDeclaration(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
switch (blockScopeContainer.kind) {
case SyntaxKind.ModuleDeclaration:
declareModuleMember(node, symbolFlags, symbolExcludes);
break;
case SyntaxKind.SourceFile:
if (isExternalModule(<SourceFile>container)) {
declareModuleMember(node, symbolFlags, symbolExcludes);
break;
}
// fall through.
default:
if (!blockScopeContainer.locals) {
blockScopeContainer.locals = {};
addToContainerChain(blockScopeContainer);
}
declareSymbol(blockScopeContainer.locals, undefined, node, symbolFlags, symbolExcludes);
}
}
function bindBlockScopedVariableDeclaration(node: Declaration) {
bindBlockScopedDeclaration(node, SymbolFlags.BlockScopedVariable, SymbolFlags.BlockScopedVariableExcludes);
}
// The binder visits every node in the syntax tree so it is a convenient place to perform a single localized
// check for reserved words used as identifiers in strict mode code.
function checkStrictModeIdentifier(node: Identifier) {
if (inStrictMode &&
node.originalKeywordKind >= SyntaxKind.FirstFutureReservedWord &&
node.originalKeywordKind <= SyntaxKind.LastFutureReservedWord &&
!isIdentifierName(node)) {
// Report error only if there are no parse errors in file
if (!file.parseDiagnostics.length) {
file.bindDiagnostics.push(createDiagnosticForNode(node,
getStrictModeIdentifierMessage(node), declarationNameToString(node)));
}
}
}
function getStrictModeIdentifierMessage(node: Node) {
// Provide specialized messages to help the user understand why we think they're in
// strict mode.
if (getContainingClass(node)) {
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Class_definitions_are_automatically_in_strict_mode;
}
if (file.externalModuleIndicator) {
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Modules_are_automatically_in_strict_mode;
}
return Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode;
}
function checkStrictModeBinaryExpression(node: BinaryExpression) {
if (inStrictMode && isLeftHandSideExpression(node.left) && isAssignmentOperator(node.operatorToken.kind)) {
// ECMA 262 (Annex C) The identifier eval or arguments may not appear as the LeftHandSideExpression of an
// Assignment operator(11.13) or of a PostfixExpression(11.3)
checkStrictModeEvalOrArguments(node, <Identifier>node.left);
}
}
function checkStrictModeCatchClause(node: CatchClause) {
// It is a SyntaxError if a TryStatement with a Catch occurs within strict code and the Identifier of the
// Catch production is eval or arguments
if (inStrictMode && node.variableDeclaration) {
checkStrictModeEvalOrArguments(node, node.variableDeclaration.name);
}
}
function checkStrictModeDeleteExpression(node: DeleteExpression) {
// Grammar checking
if (inStrictMode && node.expression.kind === SyntaxKind.Identifier) {
// When a delete operator occurs within strict mode code, a SyntaxError is thrown if its
// UnaryExpression is a direct reference to a variable, function argument, or function name
const span = getErrorSpanForNode(file, node.expression);
file.bindDiagnostics.push(createFileDiagnostic(file, span.start, span.length, Diagnostics.delete_cannot_be_called_on_an_identifier_in_strict_mode));
}
}
function isEvalOrArgumentsIdentifier(node: Node): boolean {
return node.kind === SyntaxKind.Identifier &&
((<Identifier>node).text === "eval" || (<Identifier>node).text === "arguments");
}
function checkStrictModeEvalOrArguments(contextNode: Node, name: Node) {
if (name && name.kind === SyntaxKind.Identifier) {
const identifier = <Identifier>name;
if (isEvalOrArgumentsIdentifier(identifier)) {
// We check first if the name is inside class declaration or class expression; if so give explicit message
// otherwise report generic error message.
const span = getErrorSpanForNode(file, name);
file.bindDiagnostics.push(createFileDiagnostic(file, span.start, span.length,
getStrictModeEvalOrArgumentsMessage(contextNode), identifier.text));
}
}
}
function getStrictModeEvalOrArgumentsMessage(node: Node) {
// Provide specialized messages to help the user understand why we think they're in
// strict mode.
if (getContainingClass(node)) {
return Diagnostics.Invalid_use_of_0_Class_definitions_are_automatically_in_strict_mode;
}
if (file.externalModuleIndicator) {
return Diagnostics.Invalid_use_of_0_Modules_are_automatically_in_strict_mode;
}
return Diagnostics.Invalid_use_of_0_in_strict_mode;
}
function checkStrictModeFunctionName(node: FunctionLikeDeclaration) {
if (inStrictMode) {
// It is a SyntaxError if the identifier eval or arguments appears within a FormalParameterList of a strict mode FunctionDeclaration or FunctionExpression (13.1))
checkStrictModeEvalOrArguments(node, node.name);
}
}
function getStrictModeBlockScopeFunctionDeclarationMessage(node: Node) {
// Provide specialized messages to help the user understand why we think they're in
// strict mode.
if (getContainingClass(node)) {
return Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Class_definitions_are_automatically_in_strict_mode;
}
if (file.externalModuleIndicator) {
return Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Modules_are_automatically_in_strict_mode;
}
return Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5;
}
function checkStrictModeFunctionDeclaration(node: FunctionDeclaration) {
if (languageVersion < ScriptTarget.ES6) {
// Report error if function is not top level function declaration
if (blockScopeContainer.kind !== SyntaxKind.SourceFile &&
blockScopeContainer.kind !== SyntaxKind.ModuleDeclaration &&
!isFunctionLike(blockScopeContainer)) {
// We check first if the name is inside class declaration or class expression; if so give explicit message
// otherwise report generic error message.
const errorSpan = getErrorSpanForNode(file, node);
file.bindDiagnostics.push(createFileDiagnostic(file, errorSpan.start, errorSpan.length,
getStrictModeBlockScopeFunctionDeclarationMessage(node)));
}
}
}
function checkStrictModeNumericLiteral(node: LiteralExpression) {
if (inStrictMode && node.isOctalLiteral) {
file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Octal_literals_are_not_allowed_in_strict_mode));
}
}
function checkStrictModePostfixUnaryExpression(node: PostfixUnaryExpression) {
// Grammar checking
// The identifier eval or arguments may not appear as the LeftHandSideExpression of an
// Assignment operator(11.13) or of a PostfixExpression(11.3) or as the UnaryExpression
// operated upon by a Prefix Increment(11.4.4) or a Prefix Decrement(11.4.5) operator.
if (inStrictMode) {
checkStrictModeEvalOrArguments(node, <Identifier>node.operand);
}
}
function checkStrictModePrefixUnaryExpression(node: PrefixUnaryExpression) {
// Grammar checking
if (inStrictMode) {
if (node.operator === SyntaxKind.PlusPlusToken || node.operator === SyntaxKind.MinusMinusToken) {
checkStrictModeEvalOrArguments(node, <Identifier>node.operand);
}
}
}
function checkStrictModeWithStatement(node: WithStatement) {
// Grammar checking for withStatement
if (inStrictMode) {
errorOnFirstToken(node, Diagnostics.with_statements_are_not_allowed_in_strict_mode);
}
}
function errorOnFirstToken(node: Node, message: DiagnosticMessage, arg0?: any, arg1?: any, arg2?: any) {
const span = getSpanOfTokenAtPosition(file, node.pos);
file.bindDiagnostics.push(createFileDiagnostic(file, span.start, span.length, message, arg0, arg1, arg2));
}
function getDestructuringParameterName(node: Declaration) {
return "__" + indexOf((<SignatureDeclaration>node.parent).parameters, node);
}
function bind(node: Node): void {
if (!node) {
return;
}
node.parent = parent;
const savedInStrictMode = inStrictMode;
if (!savedInStrictMode) {
updateStrictMode(node);
}
// First we bind declaration nodes to a symbol if possible. We'll both create a symbol
// and then potentially add the symbol to an appropriate symbol table. Possible
// destination symbol tables are:
//
// 1) The 'exports' table of the current container's symbol.
// 2) The 'members' table of the current container's symbol.
// 3) The 'locals' table of the current container.
//
// However, not all symbols will end up in any of these tables. 'Anonymous' symbols
// (like TypeLiterals for example) will not be put in any table.
bindWorker(node);
// Then we recurse into the children of the node to bind them as well. For certain
// symbols we do specialized work when we recurse. For example, we'll keep track of
// the current 'container' node when it changes. This helps us know which symbol table
// a local should go into for example.
if (skipTransformFlagAggregation) {
bindChildren(node);
}
else if (node.transformFlags & TransformFlags.HasComputedFlags) {
skipTransformFlagAggregation = true;
bindChildren(node);
skipTransformFlagAggregation = false;
}
else {
const savedSubtreeTransformFlags = subtreeTransformFlags;
subtreeTransformFlags = 0;
bindChildren(node);
subtreeTransformFlags = savedSubtreeTransformFlags | computeTransformFlagsForNode(node, subtreeTransformFlags);
}
inStrictMode = savedInStrictMode;
}
function updateStrictMode(node: Node) {
switch (node.kind) {
case SyntaxKind.SourceFile:
case SyntaxKind.ModuleBlock:
updateStrictModeStatementList((<SourceFile | ModuleBlock>node).statements);
return;
case SyntaxKind.Block:
if (isFunctionLike(node.parent)) {
updateStrictModeStatementList((<Block>node).statements);
}
return;
case SyntaxKind.ClassDeclaration:
case SyntaxKind.ClassExpression:
// All classes are automatically in strict mode in ES6.
inStrictMode = true;
return;
}
}
function updateStrictModeStatementList(statements: NodeArray<Statement>) {
for (const statement of statements) {
if (!isPrologueDirective(statement)) {
return;
}
if (isUseStrictPrologueDirective(<ExpressionStatement>statement)) {
inStrictMode = true;
return;
}
}
}
/// Should be called only on prologue directives (isPrologueDirective(node) should be true)
function isUseStrictPrologueDirective(node: ExpressionStatement): boolean {
const nodeText = getTextOfNodeFromSourceText(file.text, node.expression);
// Note: the node text must be exactly "use strict" or 'use strict'. It is not ok for the
// string to contain unicode escapes (as per ES5).
return nodeText === '"use strict"' || nodeText === "'use strict'";
}
function bindWorker(node: Node) {
switch (node.kind) {
/* Strict mode checks */
case SyntaxKind.Identifier:
return checkStrictModeIdentifier(<Identifier>node);
case SyntaxKind.BinaryExpression:
if (isInJavaScriptFile(node)) {
const specialKind = getSpecialPropertyAssignmentKind(node);
switch (specialKind) {
case SpecialPropertyAssignmentKind.ExportsProperty:
bindExportsPropertyAssignment(<BinaryExpression>node);
break;
case SpecialPropertyAssignmentKind.ModuleExports:
bindModuleExportsAssignment(<BinaryExpression>node);
break;
case SpecialPropertyAssignmentKind.PrototypeProperty:
bindPrototypePropertyAssignment(<BinaryExpression>node);
break;
case SpecialPropertyAssignmentKind.ThisProperty:
bindThisPropertyAssignment(<BinaryExpression>node);
break;
case SpecialPropertyAssignmentKind.None:
// Nothing to do
break;
default:
Debug.fail("Unknown special property assignment kind");
}
}
return checkStrictModeBinaryExpression(<BinaryExpression>node);
case SyntaxKind.CatchClause:
return checkStrictModeCatchClause(<CatchClause>node);
case SyntaxKind.DeleteExpression:
return checkStrictModeDeleteExpression(<DeleteExpression>node);
case SyntaxKind.NumericLiteral:
return checkStrictModeNumericLiteral(<LiteralExpression>node);
case SyntaxKind.PostfixUnaryExpression:
return checkStrictModePostfixUnaryExpression(<PostfixUnaryExpression>node);
case SyntaxKind.PrefixUnaryExpression:
return checkStrictModePrefixUnaryExpression(<PrefixUnaryExpression>node);
case SyntaxKind.WithStatement:
return checkStrictModeWithStatement(<WithStatement>node);
case SyntaxKind.ThisType:
seenThisKeyword = true;
return;
case SyntaxKind.TypePredicate:
return checkTypePredicate(node as TypePredicateNode);
case SyntaxKind.TypeParameter:
return declareSymbolAndAddToSymbolTable(<Declaration>node, SymbolFlags.TypeParameter, SymbolFlags.TypeParameterExcludes);
case SyntaxKind.Parameter:
return bindParameter(<ParameterDeclaration>node);
case SyntaxKind.VariableDeclaration:
case SyntaxKind.BindingElement:
return bindVariableDeclarationOrBindingElement(<VariableDeclaration | BindingElement>node);
case SyntaxKind.PropertyDeclaration:
case SyntaxKind.PropertySignature:
case SyntaxKind.JSDocRecordMember:
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.Property | ((<PropertyDeclaration>node).questionToken ? SymbolFlags.Optional : SymbolFlags.None), SymbolFlags.PropertyExcludes);
case SyntaxKind.PropertyAssignment:
case SyntaxKind.ShorthandPropertyAssignment:
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.Property, SymbolFlags.PropertyExcludes);
case SyntaxKind.EnumMember:
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.EnumMember, SymbolFlags.EnumMemberExcludes);
case SyntaxKind.JsxSpreadAttribute:
hasJsxSpreadAttribute = true;
return;
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
return declareSymbolAndAddToSymbolTable(<Declaration>node, SymbolFlags.Signature, SymbolFlags.None);
case SyntaxKind.MethodDeclaration:
case SyntaxKind.MethodSignature:
// If this is an ObjectLiteralExpression method, then it sits in the same space
// as other properties in the object literal. So we use SymbolFlags.PropertyExcludes
// so that it will conflict with any other object literal members with the same
// name.
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.Method | ((<MethodDeclaration>node).questionToken ? SymbolFlags.Optional : SymbolFlags.None),
isObjectLiteralMethod(node) ? SymbolFlags.PropertyExcludes : SymbolFlags.MethodExcludes);
case SyntaxKind.FunctionDeclaration:
return bindFunctionDeclaration(<FunctionDeclaration>node);
case SyntaxKind.Constructor:
return declareSymbolAndAddToSymbolTable(<Declaration>node, SymbolFlags.Constructor, /*symbolExcludes:*/ SymbolFlags.None);
case SyntaxKind.GetAccessor:
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.GetAccessor, SymbolFlags.GetAccessorExcludes);
case SyntaxKind.SetAccessor:
return bindPropertyOrMethodOrAccessor(<Declaration>node, SymbolFlags.SetAccessor, SymbolFlags.SetAccessorExcludes);
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.JSDocFunctionType:
return bindFunctionOrConstructorType(<SignatureDeclaration>node);
case SyntaxKind.TypeLiteral:
case SyntaxKind.JSDocRecordType:
return bindAnonymousDeclaration(<TypeLiteralNode>node, SymbolFlags.TypeLiteral, "__type");
case SyntaxKind.ObjectLiteralExpression:
return bindObjectLiteralExpression(<ObjectLiteralExpression>node);
case SyntaxKind.FunctionExpression:
case SyntaxKind.ArrowFunction:
return bindFunctionExpression(<FunctionExpression>node);
case SyntaxKind.CallExpression:
if (isInJavaScriptFile(node)) {
bindCallExpression(<CallExpression>node);
}
break;
// Members of classes, interfaces, and modules
case SyntaxKind.ClassExpression:
case SyntaxKind.ClassDeclaration:
return bindClassLikeDeclaration(<ClassLikeDeclaration>node);
case SyntaxKind.InterfaceDeclaration:
return bindBlockScopedDeclaration(<Declaration>node, SymbolFlags.Interface, SymbolFlags.InterfaceExcludes);
case SyntaxKind.TypeAliasDeclaration:
return bindBlockScopedDeclaration(<Declaration>node, SymbolFlags.TypeAlias, SymbolFlags.TypeAliasExcludes);
case SyntaxKind.EnumDeclaration:
return bindEnumDeclaration(<EnumDeclaration>node);
case SyntaxKind.ModuleDeclaration:
return bindModuleDeclaration(<ModuleDeclaration>node);
// Imports and exports
case SyntaxKind.ImportEqualsDeclaration:
case SyntaxKind.NamespaceImport:
case SyntaxKind.ImportSpecifier:
case SyntaxKind.ExportSpecifier:
return declareSymbolAndAddToSymbolTable(<Declaration>node, SymbolFlags.Alias, SymbolFlags.AliasExcludes);
case SyntaxKind.GlobalModuleExportDeclaration:
return bindGlobalModuleExportDeclaration(<GlobalModuleExportDeclaration>node);
case SyntaxKind.ImportClause:
return bindImportClause(<ImportClause>node);
case SyntaxKind.ExportDeclaration:
return bindExportDeclaration(<ExportDeclaration>node);
case SyntaxKind.ExportAssignment:
return bindExportAssignment(<ExportAssignment>node);
case SyntaxKind.SourceFile:
return bindSourceFileIfExternalModule();
}
}
function checkTypePredicate(node: TypePredicateNode) {
const { parameterName, type } = node;
if (parameterName && parameterName.kind === SyntaxKind.Identifier) {
checkStrictModeIdentifier(parameterName as Identifier);
}
if (parameterName && parameterName.kind === SyntaxKind.ThisType) {
seenThisKeyword = true;
}
bind(type);
}
function bindSourceFileIfExternalModule() {
setExportContextFlag(file);
if (isExternalModule(file)) {
bindSourceFileAsExternalModule();
}
}
function bindSourceFileAsExternalModule() {
bindAnonymousDeclaration(file, SymbolFlags.ValueModule, `"${removeFileExtension(file.fileName) }"`);
}
function bindExportAssignment(node: ExportAssignment | BinaryExpression) {
const boundExpression = node.kind === SyntaxKind.ExportAssignment ? (<ExportAssignment>node).expression : (<BinaryExpression>node).right;
if (!container.symbol || !container.symbol.exports) {
// Export assignment in some sort of block construct
bindAnonymousDeclaration(node, SymbolFlags.Alias, getDeclarationName(node));
}
else if (boundExpression.kind === SyntaxKind.Identifier && node.kind === SyntaxKind.ExportAssignment) {
// An export default clause with an identifier exports all meanings of that identifier
declareSymbol(container.symbol.exports, container.symbol, node, SymbolFlags.Alias, SymbolFlags.PropertyExcludes | SymbolFlags.AliasExcludes);
}
else {
// An export default clause with an expression exports a value
declareSymbol(container.symbol.exports, container.symbol, node, SymbolFlags.Property, SymbolFlags.PropertyExcludes | SymbolFlags.AliasExcludes);
}
}
function bindGlobalModuleExportDeclaration(node: GlobalModuleExportDeclaration) {
if (node.modifiers && node.modifiers.length) {
file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Modifiers_cannot_appear_here));
}
if (node.parent.kind !== SyntaxKind.SourceFile) {
file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Global_module_exports_may_only_appear_at_top_level));
return;
}
else {
const parent = node.parent as SourceFile;
if (!isExternalModule(parent)) {
file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Global_module_exports_may_only_appear_in_module_files));
return;
}
if (!parent.isDeclarationFile) {
file.bindDiagnostics.push(createDiagnosticForNode(node, Diagnostics.Global_module_exports_may_only_appear_in_declaration_files));
return;
}
}
file.symbol.globalExports = file.symbol.globalExports || {};
declareSymbol(file.symbol.globalExports, file.symbol, node, SymbolFlags.Alias, SymbolFlags.AliasExcludes);
}
function bindExportDeclaration(node: ExportDeclaration) {
if (!container.symbol || !container.symbol.exports) {
// Export * in some sort of block construct
bindAnonymousDeclaration(node, SymbolFlags.ExportStar, getDeclarationName(node));
}
else if (!node.exportClause) {
// All export * declarations are collected in an __export symbol
declareSymbol(container.symbol.exports, container.symbol, node, SymbolFlags.ExportStar, SymbolFlags.None);
}
}
function bindImportClause(node: ImportClause) {
if (node.name) {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.Alias, SymbolFlags.AliasExcludes);
}
}
function setCommonJsModuleIndicator(node: Node) {
if (!file.commonJsModuleIndicator) {
file.commonJsModuleIndicator = node;
bindSourceFileAsExternalModule();
}
}
function bindExportsPropertyAssignment(node: BinaryExpression) {
// When we create a property via 'exports.foo = bar', the 'exports.foo' property access
// expression is the declaration
setCommonJsModuleIndicator(node);
declareSymbol(file.symbol.exports, file.symbol, <PropertyAccessExpression>node.left, SymbolFlags.Property | SymbolFlags.Export, SymbolFlags.None);
}
function bindModuleExportsAssignment(node: BinaryExpression) {
// 'module.exports = expr' assignment
setCommonJsModuleIndicator(node);
declareSymbol(file.symbol.exports, file.symbol, node, SymbolFlags.Property | SymbolFlags.Export | SymbolFlags.ValueModule, SymbolFlags.None);
}
function bindThisPropertyAssignment(node: BinaryExpression) {
// Declare a 'member' in case it turns out the container was an ES5 class
if (container.kind === SyntaxKind.FunctionExpression || container.kind === SyntaxKind.FunctionDeclaration) {
container.symbol.members = container.symbol.members || {};
// It's acceptable for multiple 'this' assignments of the same identifier to occur
declareSymbol(container.symbol.members, container.symbol, node, SymbolFlags.Property, SymbolFlags.PropertyExcludes & ~SymbolFlags.Property);
}
}
function bindPrototypePropertyAssignment(node: BinaryExpression) {
// We saw a node of the form 'x.prototype.y = z'. Declare a 'member' y on x if x was a function.
// Look up the function in the local scope, since prototype assignments should
// follow the function declaration
const leftSideOfAssignment = node.left as PropertyAccessExpression;
const classPrototype = leftSideOfAssignment.expression as PropertyAccessExpression;
const constructorFunction = classPrototype.expression as Identifier;
// Fix up parent pointers since we're going to use these nodes before we bind into them
leftSideOfAssignment.parent = node;
constructorFunction.parent = classPrototype;
classPrototype.parent = leftSideOfAssignment;
const funcSymbol = container.locals[constructorFunction.text];
if (!funcSymbol || !(funcSymbol.flags & SymbolFlags.Function)) {
return;
}
// Set up the members collection if it doesn't exist already
if (!funcSymbol.members) {
funcSymbol.members = {};
}
// Declare the method/property
declareSymbol(funcSymbol.members, funcSymbol, leftSideOfAssignment, SymbolFlags.Property, SymbolFlags.PropertyExcludes);
}
function bindCallExpression(node: CallExpression) {
// We're only inspecting call expressions to detect CommonJS modules, so we can skip
// this check if we've already seen the module indicator
if (!file.commonJsModuleIndicator && isRequireCall(node, /*checkArgumentIsStringLiteral*/false)) {
setCommonJsModuleIndicator(node);
}
}
function bindClassLikeDeclaration(node: ClassLikeDeclaration) {
if (!isDeclarationFile(file) && !isInAmbientContext(node)) {
if (getClassExtendsHeritageClauseElement(node) !== undefined) {
hasClassExtends = true;
}
if (nodeIsDecorated(node)) {
hasDecorators = true;
}
}
if (node.kind === SyntaxKind.ClassDeclaration) {
bindBlockScopedDeclaration(node, SymbolFlags.Class, SymbolFlags.ClassExcludes);
}
else {
const bindingName = node.name ? node.name.text : "__class";
bindAnonymousDeclaration(node, SymbolFlags.Class, bindingName);
// Add name of class expression into the map for semantic classifier
if (node.name) {
classifiableNames[node.name.text] = node.name.text;
}
}
const symbol = node.symbol;
// 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'.
//
// Note: we check for this here because this class may be merging into a module. The
// module might have an exported variable called 'prototype'. We can't allow that as
// that would clash with the built-in 'prototype' for the class.
const prototypeSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Prototype, "prototype");
if (hasProperty(symbol.exports, prototypeSymbol.name)) {
if (node.name) {
node.name.parent = node;
}
file.bindDiagnostics.push(createDiagnosticForNode(symbol.exports[prototypeSymbol.name].declarations[0],
Diagnostics.Duplicate_identifier_0, prototypeSymbol.name));
}
symbol.exports[prototypeSymbol.name] = prototypeSymbol;
prototypeSymbol.parent = symbol;
}
function bindEnumDeclaration(node: EnumDeclaration) {
return isConst(node)
? bindBlockScopedDeclaration(node, SymbolFlags.ConstEnum, SymbolFlags.ConstEnumExcludes)
: bindBlockScopedDeclaration(node, SymbolFlags.RegularEnum, SymbolFlags.RegularEnumExcludes);
}
function bindVariableDeclarationOrBindingElement(node: VariableDeclaration | BindingElement) {
if (inStrictMode) {
checkStrictModeEvalOrArguments(node, node.name);
}
if (!isBindingPattern(node.name)) {
if (isBlockOrCatchScoped(node)) {
bindBlockScopedVariableDeclaration(node);
}
else if (isParameterDeclaration(node)) {
// It is safe to walk up parent chain to find whether the node is a destructing parameter declaration
// because its parent chain has already been set up, since parents are set before descending into children.
//
// If node is a binding element in parameter declaration, we need to use ParameterExcludes.
// Using ParameterExcludes flag allows the compiler to report an error on duplicate identifiers in Parameter Declaration
// For example:
// function foo([a,a]) {} // Duplicate Identifier error
// function bar(a,a) {} // Duplicate Identifier error, parameter declaration in this case is handled in bindParameter
// // which correctly set excluded symbols
declareSymbolAndAddToSymbolTable(node, SymbolFlags.FunctionScopedVariable, SymbolFlags.ParameterExcludes);
}
else {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.FunctionScopedVariable, SymbolFlags.FunctionScopedVariableExcludes);
}
}
}
function bindParameter(node: ParameterDeclaration) {
if (!isDeclarationFile(file) &&
!isInAmbientContext(node) &&
nodeIsDecorated(node)) {
hasDecorators = true;
hasParameterDecorators = true;
}
if (inStrictMode) {
// It is a SyntaxError if the identifier eval or arguments appears within a FormalParameterList of a
// strict mode FunctionLikeDeclaration or FunctionExpression(13.1)
checkStrictModeEvalOrArguments(node, node.name);
}
if (isBindingPattern(node.name)) {
bindAnonymousDeclaration(node, SymbolFlags.FunctionScopedVariable, getDestructuringParameterName(node));
}
else {
declareSymbolAndAddToSymbolTable(node, SymbolFlags.FunctionScopedVariable, SymbolFlags.ParameterExcludes);
}
// If this is a property-parameter, then also declare the property symbol into the
// containing class.
if (isParameterPropertyDeclaration(node)) {
const classDeclaration = <ClassLikeDeclaration>node.parent.parent;
declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, SymbolFlags.Property, SymbolFlags.PropertyExcludes);
}
}
function bindFunctionDeclaration(node: FunctionDeclaration) {
if (!isDeclarationFile(file) && !isInAmbientContext(node)) {
if (isAsyncFunctionLike(node)) {
hasAsyncFunctions = true;
}
}
checkStrictModeFunctionName(<FunctionDeclaration>node);
if (inStrictMode) {
checkStrictModeFunctionDeclaration(node);
return bindBlockScopedDeclaration(node, SymbolFlags.Function, SymbolFlags.FunctionExcludes);
}
else {
return declareSymbolAndAddToSymbolTable(<Declaration>node, SymbolFlags.Function, SymbolFlags.FunctionExcludes);
}
}
function bindFunctionExpression(node: FunctionExpression) {
if (!isDeclarationFile(file) && !isInAmbientContext(node)) {
if (isAsyncFunctionLike(node)) {
hasAsyncFunctions = true;
}
}
checkStrictModeFunctionName(<FunctionExpression>node);
const bindingName = (<FunctionExpression>node).name ? (<FunctionExpression>node).name.text : "__function";
return bindAnonymousDeclaration(<FunctionExpression>node, SymbolFlags.Function, bindingName);
}
function bindPropertyOrMethodOrAccessor(node: Declaration, symbolFlags: SymbolFlags, symbolExcludes: SymbolFlags) {
if (!isDeclarationFile(file) && !isInAmbientContext(node)) {
if (isAsyncFunctionLike(node)) {
hasAsyncFunctions = true;
}
if (nodeIsDecorated(node)) {
hasDecorators = true;
}
}
return hasDynamicName(node)
? bindAnonymousDeclaration(node, symbolFlags, "__computed")
: declareSymbolAndAddToSymbolTable(node, symbolFlags, symbolExcludes);
}
// reachability checks
function pushNamedLabel(name: Identifier): boolean {
initializeReachabilityStateIfNecessary();
if (hasProperty(labelIndexMap, name.text)) {
return false;
}
labelIndexMap[name.text] = labelStack.push(Reachability.Uninitialized) - 1;
return true;
}
function pushImplicitLabel(): number {
initializeReachabilityStateIfNecessary();
const index = labelStack.push(Reachability.Uninitialized) - 1;
implicitLabels.push(index);
return index;
}
function popNamedLabel(label: Identifier, outerState: Reachability): void {
const index = labelIndexMap[label.text];
Debug.assert(index !== undefined);
Debug.assert(labelStack.length == index + 1);
labelIndexMap[label.text] = undefined;
setCurrentStateAtLabel(labelStack.pop(), outerState, label);
}
function popImplicitLabel(implicitLabelIndex: number, outerState: Reachability): void {
if (labelStack.length !== implicitLabelIndex + 1) {
Debug.assert(false, `Label stack: ${labelStack.length}, index:${implicitLabelIndex}`);
}
const i = implicitLabels.pop();
if (implicitLabelIndex !== i) {
Debug.assert(false, `i: ${i}, index: ${implicitLabelIndex}`);
}
setCurrentStateAtLabel(labelStack.pop(), outerState, /*name*/ undefined);
}
function setCurrentStateAtLabel(innerMergedState: Reachability, outerState: Reachability, label: Identifier): void {
if (innerMergedState === Reachability.Uninitialized) {
if (label && !options.allowUnusedLabels) {
file.bindDiagnostics.push(createDiagnosticForNode(label, Diagnostics.Unused_label));
}
currentReachabilityState = outerState;
}
else {
currentReachabilityState = or(innerMergedState, outerState);
}
}
function jumpToLabel(label: Identifier, outerState: Reachability): boolean {
initializeReachabilityStateIfNecessary();
const index = label ? labelIndexMap[label.text] : lastOrUndefined(implicitLabels);
if (index === undefined) {
// reference to unknown label or
// break/continue used outside of loops
return false;
}
const stateAtLabel = labelStack[index];
labelStack[index] = stateAtLabel === Reachability.Uninitialized ? outerState : or(stateAtLabel, outerState);
return true;
}
function checkUnreachable(node: Node): boolean {
switch (currentReachabilityState) {
case Reachability.Unreachable:
const reportError =
// report error on all statements except empty ones
(isStatementButNotDeclaration(node) && node.kind !== SyntaxKind.EmptyStatement) ||
// report error on ExportAssignment
node.kind === SyntaxKind.ExportAssignment ||
// report error on class declarations
node.kind === SyntaxKind.ClassDeclaration ||
// report error on instantiated modules or const-enums only modules if preserveConstEnums is set
(node.kind === SyntaxKind.ModuleDeclaration && shouldReportErrorOnModuleDeclaration(<ModuleDeclaration>node)) ||
// report error on regular enums and const enums if preserveConstEnums is set
(node.kind === SyntaxKind.EnumDeclaration && (!isConstEnumDeclaration(node) || options.preserveConstEnums));
if (reportError) {
currentReachabilityState = Reachability.ReportedUnreachable;
// unreachable code is reported if
// - user has explicitly asked about it AND
// - statement is in not ambient context (statements in ambient context is already an error
// so we should not report extras) AND
// - node is not variable statement OR
// - node is block scoped variable statement OR
// - node is not block scoped variable statement and at least one variable declaration has initializer
// Rationale: we don't want to report errors on non-initialized var's since they are hoisted
// On the other side we do want to report errors on non-initialized 'lets' because of TDZ
const reportUnreachableCode =
!options.allowUnreachableCode &&
!isInAmbientContext(node) &&
(
node.kind !== SyntaxKind.VariableStatement ||
getCombinedNodeFlags((<VariableStatement>node).declarationList) & NodeFlags.BlockScoped ||
forEach((<VariableStatement>node).declarationList.declarations, d => d.initializer)
);
if (reportUnreachableCode) {
errorOnFirstToken(node, Diagnostics.Unreachable_code_detected);
}
}
case Reachability.ReportedUnreachable:
return true;
default:
return false;
}
function shouldReportErrorOnModuleDeclaration(node: ModuleDeclaration): boolean {
const instanceState = getModuleInstanceState(node);
return instanceState === ModuleInstanceState.Instantiated || (instanceState === ModuleInstanceState.ConstEnumOnly && options.preserveConstEnums);
}
}
function initializeReachabilityStateIfNecessary(): void {
if (labelIndexMap) {
return;
}
currentReachabilityState = Reachability.Reachable;
labelIndexMap = {};
labelStack = [];
implicitLabels = [];
}
}
/**
* Computes the transform flags for a node, given the transform flags of its subtree
*
* @param node The node to analyze
* @param subtreeFlags Transform flags computed for this node's subtree
*/
export function computeTransformFlagsForNode(node: Node, subtreeFlags: TransformFlags): TransformFlags {
// Mark transformations needed for each node
let transformFlags = TransformFlags.None;
let excludeFlags = TransformFlags.None;
switch (node.kind) {
case SyntaxKind.PublicKeyword:
case SyntaxKind.PrivateKeyword:
case SyntaxKind.ProtectedKeyword:
case SyntaxKind.AbstractKeyword:
case SyntaxKind.DeclareKeyword:
case SyntaxKind.AsyncKeyword:
case SyntaxKind.ConstKeyword:
case SyntaxKind.AwaitExpression:
case SyntaxKind.EnumDeclaration:
case SyntaxKind.EnumMember:
case SyntaxKind.TypeAssertionExpression:
case SyntaxKind.AsExpression:
case SyntaxKind.ReadonlyKeyword:
// These nodes are TypeScript syntax.
transformFlags = TransformFlags.AssertTypeScript;
break;
case SyntaxKind.JsxElement:
case SyntaxKind.JsxSelfClosingElement:
case SyntaxKind.JsxOpeningElement:
case SyntaxKind.JsxText:
case SyntaxKind.JsxClosingElement:
case SyntaxKind.JsxAttribute:
case SyntaxKind.JsxSpreadAttribute:
case SyntaxKind.JsxExpression:
// These nodes are Jsx syntax.
transformFlags = TransformFlags.AssertJsx;
break;
case SyntaxKind.ExportKeyword:
// This node is both ES6 and TypeScript syntax.
transformFlags = TransformFlags.AssertES6 | TransformFlags.TypeScript;
break;
case SyntaxKind.DefaultKeyword:
case SyntaxKind.NoSubstitutionTemplateLiteral:
case SyntaxKind.TemplateHead:
case SyntaxKind.TemplateMiddle:
case SyntaxKind.TemplateTail:
case SyntaxKind.TemplateExpression:
case SyntaxKind.TaggedTemplateExpression:
case SyntaxKind.ShorthandPropertyAssignment:
case SyntaxKind.ForOfStatement:
case SyntaxKind.YieldExpression:
// These nodes are ES6 syntax.
transformFlags = TransformFlags.AssertES6;
break;
case SyntaxKind.AnyKeyword:
case SyntaxKind.NumberKeyword:
case SyntaxKind.StringKeyword:
case SyntaxKind.BooleanKeyword:
case SyntaxKind.SymbolKeyword:
case SyntaxKind.VoidKeyword:
case SyntaxKind.TypeParameter:
case SyntaxKind.PropertySignature:
case SyntaxKind.MethodSignature:
case SyntaxKind.CallSignature:
case SyntaxKind.ConstructSignature:
case SyntaxKind.IndexSignature:
case SyntaxKind.TypePredicate:
case SyntaxKind.TypeReference:
case SyntaxKind.FunctionType:
case SyntaxKind.ConstructorType:
case SyntaxKind.TypeQuery:
case SyntaxKind.TypeLiteral:
case SyntaxKind.ArrayType:
case SyntaxKind.TupleType:
case SyntaxKind.UnionType:
case SyntaxKind.IntersectionType:
case SyntaxKind.ParenthesizedType:
case SyntaxKind.InterfaceDeclaration:
case SyntaxKind.TypeAliasDeclaration:
case SyntaxKind.ThisType:
case SyntaxKind.StringLiteralType:
// Types and signatures are TypeScript syntax, and exclude all other facts.
subtreeFlags = TransformFlags.None;
excludeFlags = TransformFlags.TypeExcludes;
transformFlags = TransformFlags.AssertTypeScript;
break;
case SyntaxKind.ComputedPropertyName:
// Even though computed property names are ES6, we don't treat them as such.
// This is so that they can flow through PropertyName transforms unaffected.
// Instead, we mark the container as ES6, so that it can properly handle the transform.
transformFlags = TransformFlags.ContainsComputedPropertyName;
if (subtreeFlags & TransformFlags.ContainsLexicalThis) {
// A computed method name like `[this.getName()](x: string) { ... }` needs to
// distinguish itself from the normal case of a method body containing `this`:
// `this` inside a method doesn't need to be rewritten (the method provides `this`),
// whereas `this` inside a computed name *might* need to be rewritten if the class/object
// is inside an arrow function:
// `_this = this; () => class K { [_this.getName()]() { ... } }`
// To make this distinction, use ContainsLexicalThisInComputedPropertyName
// instead of ContainsLexicalThis for computed property names
transformFlags |= TransformFlags.ContainsLexicalThisInComputedPropertyName;
}
break;
case SyntaxKind.SpreadElementExpression:
// This node is ES6 syntax, but is handled by a containing node.
transformFlags = TransformFlags.ContainsSpreadElementExpression;
break;
case SyntaxKind.SuperKeyword:
// This node is ES6 syntax.
transformFlags = TransformFlags.AssertES6;
break;
case SyntaxKind.ThisKeyword:
// Mark this node and its ancestors as containing a lexical `this` keyword.
transformFlags = TransformFlags.ContainsLexicalThis;
break;
case SyntaxKind.ObjectBindingPattern:
case SyntaxKind.ArrayBindingPattern:
// These nodes are ES6 syntax.
transformFlags = TransformFlags.AssertES6;
break;
case SyntaxKind.Decorator:
// This node is TypeScript syntax, and marks its container as also being TypeScript syntax.
transformFlags = TransformFlags.AssertTypeScript | TransformFlags.ContainsDecorators;
break;
case SyntaxKind.ObjectLiteralExpression:
excludeFlags = TransformFlags.ObjectLiteralExcludes;
if (subtreeFlags & TransformFlags.ContainsComputedPropertyName) {
// If an ObjectLiteralExpression contains a ComputedPropertyName, then it
// is an ES6 node.
transformFlags = TransformFlags.AssertES6;
}
if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
// A computed property name containing `this` might need to be rewritten,
// so propagate the ContainsLexicalThis flag upward.
transformFlags |= TransformFlags.ContainsLexicalThis;
}
break;
case SyntaxKind.CallExpression:
return computeCallExpression(<CallExpression>node, subtreeFlags);
case SyntaxKind.ArrayLiteralExpression:
case SyntaxKind.NewExpression:
excludeFlags = TransformFlags.ArrayLiteralOrCallOrNewExcludes;
if (subtreeFlags & TransformFlags.ContainsSpreadElementExpression) {
// If the this node contains a SpreadElementExpression, then it is an ES6
// node.
transformFlags = TransformFlags.AssertES6;
}
break;
case SyntaxKind.ModuleDeclaration:
// An ambient declaration is TypeScript syntax.
if (hasModifier(node, ModifierFlags.Ambient)) {
subtreeFlags = TransformFlags.None;
}
// This node is TypeScript syntax, and excludes markers that should not escape the module scope.
excludeFlags = TransformFlags.ModuleExcludes;
transformFlags = TransformFlags.AssertTypeScript;
break;
case SyntaxKind.ParenthesizedExpression:
return computeParenthesizedExpression(<ParenthesizedExpression>node, subtreeFlags);
case SyntaxKind.BinaryExpression:
return computeBinaryExpression(<BinaryExpression>node, subtreeFlags);
case SyntaxKind.ExpressionStatement:
// If the expression of an expression statement is a destructuring assignment,
// then we treat the statement as ES6 so that we can indicate that we do not
// need to hold on to the right-hand side.
if ((<ExpressionStatement>node).expression.transformFlags & TransformFlags.DestructuringAssignment) {
transformFlags = TransformFlags.AssertES6;
}
break;
case SyntaxKind.Parameter:
return computeParameter(<ParameterDeclaration>node, subtreeFlags);
case SyntaxKind.ArrowFunction:
return computeArrowFunction(<ArrowFunction>node, subtreeFlags);
case SyntaxKind.FunctionExpression:
return computeFunctionExpression(<FunctionExpression>node, subtreeFlags);
case SyntaxKind.FunctionDeclaration:
return computeFunctionDeclaration(<FunctionDeclaration>node, subtreeFlags);
case SyntaxKind.VariableDeclaration:
return computeVariableDeclaration(<VariableDeclaration>node, subtreeFlags);
case SyntaxKind.VariableDeclarationList:
// If a VariableDeclarationList is `let` or `const`, then it is ES6 syntax.
if (node.flags & NodeFlags.BlockScoped) {
transformFlags = TransformFlags.AssertES6 | TransformFlags.ContainsBlockScopedBinding;
}
break;
case SyntaxKind.VariableStatement:
return computeVariableStatement(<VariableStatement>node, subtreeFlags);
case SyntaxKind.LabeledStatement:
return computeLabeledStatement(<LabeledStatement>node, subtreeFlags);
case SyntaxKind.DoStatement:
case SyntaxKind.WhileStatement:
case SyntaxKind.ForStatement:
case SyntaxKind.ForInStatement:
// A loop containing a block scoped binding *may* need to be transformed from ES6.
if (subtreeFlags & TransformFlags.ContainsBlockScopedBinding) {
transformFlags = TransformFlags.AssertES6;
}
break;
case SyntaxKind.ClassDeclaration:
return computeClassDeclaration(<ClassDeclaration>node, subtreeFlags);
case SyntaxKind.ClassExpression:
return computeClassExpression(<ClassExpression>node, subtreeFlags);
case SyntaxKind.HeritageClause:
if ((<HeritageClause>node).token === SyntaxKind.ExtendsKeyword) {
// An `extends` HeritageClause is ES6 syntax.
transformFlags = TransformFlags.AssertES6;
}
else {
// An `implements` HeritageClause is TypeScript syntax.
Debug.assert((<HeritageClause>node).token === SyntaxKind.ImplementsKeyword);
transformFlags = TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.ExpressionWithTypeArguments:
// An ExpressionWithTypeArguments is ES6 syntax, as it is used in the
// extends clause of a class.
transformFlags = TransformFlags.AssertES6;
// If an ExpressionWithTypeArguments contains type arguments, then it
// is TypeScript syntax.
if ((<ExpressionWithTypeArguments>node).typeArguments) {
transformFlags |= TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.Constructor:
// A Constructor is ES6 syntax.
excludeFlags = TransformFlags.ConstructorExcludes;
transformFlags = TransformFlags.AssertES6;
// An overload constructor is TypeScript syntax.
if (!(<ConstructorDeclaration>node).body) {
transformFlags |= TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.PropertyDeclaration:
// A PropertyDeclaration is TypeScript syntax.
transformFlags = TransformFlags.AssertTypeScript;
// If the PropertyDeclaration has an initializer, we need to inform its ancestor
// so that it handle the transformation.
if ((<PropertyDeclaration>node).initializer) {
transformFlags |= TransformFlags.ContainsPropertyInitializer;
}
break;
case SyntaxKind.MethodDeclaration:
// A MethodDeclaration is ES6 syntax.
excludeFlags = TransformFlags.MethodOrAccessorExcludes;
transformFlags = TransformFlags.AssertES6;
// A MethodDeclaration is TypeScript syntax if it is either async, abstract, overloaded,
// generic, or has both a computed property name and a decorator.
if ((<MethodDeclaration>node).body === undefined
|| (<MethodDeclaration>node).typeParameters !== undefined
|| hasModifier(node, ModifierFlags.Async | ModifierFlags.Abstract)
|| (subtreeFlags & TransformFlags.ContainsDecorators
&& subtreeFlags & TransformFlags.ContainsComputedPropertyName)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.GetAccessor:
case SyntaxKind.SetAccessor:
// A GetAccessor or SetAccessor is ES5 syntax.
excludeFlags = TransformFlags.MethodOrAccessorExcludes;
// A GetAccessor or SetAccessor is TypeScript syntax if it is either abstract,
// or has both a computed property name and a decorator.
if ((<AccessorDeclaration>node).body === undefined
|| hasModifier(node, ModifierFlags.Abstract)
|| (subtreeFlags & TransformFlags.ContainsDecorators
&& subtreeFlags & TransformFlags.ContainsComputedPropertyName)) {
transformFlags = TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.ImportEqualsDeclaration:
// An ImportEqualsDeclaration with a namespace reference is TypeScript.
if (!isExternalModuleImportEqualsDeclaration(node)) {
transformFlags = TransformFlags.AssertTypeScript;
}
break;
case SyntaxKind.PropertyAccessExpression:
// If a PropertyAccessExpression starts with a super keyword, then it is
// ES6 syntax, and requires a lexical `this` binding.
if ((<PropertyAccessExpression>node).expression.kind === SyntaxKind.SuperKeyword) {
transformFlags = TransformFlags.ContainsLexicalThis;
}
break;
case SyntaxKind.SourceFile:
if (subtreeFlags & TransformFlags.ContainsCapturedLexicalThis) {
transformFlags = TransformFlags.AssertES6;
}
break;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, excludeFlags);
}
function computeCallExpression(node: CallExpression, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
if (subtreeFlags & TransformFlags.ContainsSpreadElementExpression
|| isSuperCall(node)
|| isSuperPropertyCall(node)) {
// If the this node contains a SpreadElementExpression, or is a super call, then it is an ES6
// node.
transformFlags = TransformFlags.AssertES6;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.ArrayLiteralOrCallOrNewExcludes);
}
function computeBinaryExpression(node: BinaryExpression, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
if (isDestructuringAssignment(node)) {
// Destructuring assignments are ES6 syntax.
transformFlags = TransformFlags.AssertES6 | TransformFlags.DestructuringAssignment;
}
else if (isExponentiation(node.operatorToken)) {
// Exponentiation is ES7 syntax.
transformFlags = TransformFlags.AssertES7;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function isDestructuringAssignment(node: BinaryExpression) {
return node.operatorToken.kind === SyntaxKind.EqualsToken
&& isObjectOrArrayLiteral(node.left);
}
function isObjectOrArrayLiteral(node: Node) {
switch (node.kind) {
case SyntaxKind.ObjectLiteralExpression:
case SyntaxKind.ArrayLiteralExpression:
return true;
}
return false;
}
function isExponentiation(operatorToken: Node) {
switch (operatorToken.kind) {
case SyntaxKind.AsteriskAsteriskToken:
case SyntaxKind.AsteriskAsteriskEqualsToken:
return true;
}
return false;
}
function computeParameter(node: ParameterDeclaration, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
// If the parameter has a question token, then it is TypeScript syntax.
if (isDefined(node.questionToken)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
// If a parameter has an accessibility modifier, then it is TypeScript syntax.
if (hasModifier(node, ModifierFlags.AccessibilityModifier)) {
transformFlags |= TransformFlags.AssertTypeScript | TransformFlags.ContainsParameterPropertyAssignments;
}
// If a parameter has an initializer, a binding pattern or a dotDotDot token, then
// it is ES6 syntax and its container must emit default value assignments or parameter destructuring downlevel.
if (isDefined(node.initializer) || isDefined(node.dotDotDotToken) || isBindingPattern(node.name)) {
transformFlags |= TransformFlags.AssertES6 | TransformFlags.ContainsDefaultValueAssignments;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function computeParenthesizedExpression(node: ParenthesizedExpression, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
// If the node is synthesized, it means the emitter put the parentheses there,
// not the user. If we didn't want them, the emitter would not have put them
// there.
if (node.expression.kind === SyntaxKind.AsExpression
|| node.expression.kind === SyntaxKind.TypeAssertionExpression) {
transformFlags = TransformFlags.AssertTypeScript;
}
// If the expression of a ParenthesizedExpression is a destructuring assignment,
// then the ParenthesizedExpression is a destructuring assignment.
if (node.expression.transformFlags & TransformFlags.DestructuringAssignment) {
transformFlags |= TransformFlags.DestructuringAssignment;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function computeClassDeclaration(node: ClassDeclaration, subtreeFlags: TransformFlags) {
// An ambient declaration is TypeScript syntax.
if (hasModifier(node, ModifierFlags.Ambient)) {
return updateTransformFlags(node, TransformFlags.None, TransformFlags.TypeScript, TransformFlags.ClassExcludes);
}
// A ClassDeclaration is ES6 syntax.
let transformFlags = TransformFlags.AssertES6;
// A class with a parameter property assignment, property initializer, or decorator is
// TypeScript syntax.
// An exported declaration may be TypeScript syntax.
if (subtreeFlags
& (TransformFlags.ContainsParameterPropertyAssignments
| TransformFlags.ContainsPropertyInitializer
| TransformFlags.ContainsDecorators)
|| hasModifier(node, ModifierFlags.Export)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
// A computed property name containing `this` might need to be rewritten,
// so propagate the ContainsLexicalThis flag upward.
transformFlags |= TransformFlags.ContainsLexicalThis;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.ClassExcludes);
}
function computeClassExpression(node: ClassExpression, subtreeFlags: TransformFlags) {
// A ClassExpression is ES6 syntax.
let transformFlags = TransformFlags.AssertES6;
// A class with a parameter property assignment, property initializer, or decorator is
// TypeScript syntax.
if (subtreeFlags
& (TransformFlags.ContainsParameterPropertyAssignments
| TransformFlags.ContainsPropertyInitializer
| TransformFlags.ContainsDecorators)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
if (subtreeFlags & TransformFlags.ContainsLexicalThisInComputedPropertyName) {
// A computed property name containing `this` might need to be rewritten,
// so propagate the ContainsLexicalThis flag upward.
transformFlags |= TransformFlags.ContainsLexicalThis;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.ClassExcludes);
}
function computeFunctionDeclaration(node: FunctionDeclaration, subtreeFlags: TransformFlags) {
const modifiers = getModifierFlags(node);
// An ambient declaration is TypeScript syntax.
// A FunctionDeclaration without a body is an overload and is TypeScript syntax.
if (!node.body || modifiers & ModifierFlags.Ambient) {
return updateTransformFlags(node, TransformFlags.None, TransformFlags.AssertTypeScript, TransformFlags.FunctionExcludes);
}
let transformFlags = TransformFlags.None;
// If a FunctionDeclaration is exported, then it is either ES6 or TypeScript syntax.
if (modifiers & ModifierFlags.Export) {
transformFlags |= TransformFlags.AssertTypeScript | TransformFlags.AssertES6;
}
// If a FunctionDeclaration is async, then it is TypeScript syntax.
if (modifiers & ModifierFlags.Async) {
transformFlags |= TransformFlags.AssertTypeScript;
}
// If a FunctionDeclaration has an asterisk token, is exported, or its
// subtree has marked the container as needing to capture the lexical `this`,
// then this node is ES6 syntax.
if (subtreeFlags & (TransformFlags.ContainsCapturedLexicalThis | TransformFlags.ContainsDefaultValueAssignments)
|| node.asteriskToken) {
transformFlags |= TransformFlags.AssertES6;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.FunctionExcludes);
}
function computeFunctionExpression(node: FunctionExpression, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
// An async function expression is TypeScript syntax.
if (hasModifier(node, ModifierFlags.Async)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
// If a FunctionExpression contains an asterisk token, or its subtree has marked the container
// as needing to capture the lexical this, then this node is ES6 syntax.
if (subtreeFlags & (TransformFlags.ContainsCapturedLexicalThis | TransformFlags.ContainsDefaultValueAssignments)
|| node.asteriskToken) {
transformFlags |= TransformFlags.AssertES6;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.FunctionExcludes);
}
function computeArrowFunction(node: ArrowFunction, subtreeFlags: TransformFlags) {
// An ArrowFunction is ES6 syntax, and excludes markers that should not escape the scope of an ArrowFunction.
let transformFlags = TransformFlags.AssertES6;
// An async arrow function is TypeScript syntax.
if (hasModifier(node, ModifierFlags.Async)) {
transformFlags |= TransformFlags.AssertTypeScript;
}
// If an ArrowFunction contains a lexical this, its container must capture the lexical this.
if (subtreeFlags & TransformFlags.ContainsLexicalThis) {
transformFlags |= TransformFlags.ContainsCapturedLexicalThis;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.ArrowFunctionExcludes);
}
function computeVariableDeclaration(node: VariableDeclaration, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
// A VariableDeclaration with a binding pattern is ES6 syntax.
if (isBindingPattern((<VariableDeclaration>node).name)) {
transformFlags = TransformFlags.AssertES6;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function computeVariableStatement(node: VariableStatement, subtreeFlags: TransformFlags) {
const modifiers = getModifierFlags(node);
// An ambient declaration is TypeScript syntax.
if (modifiers & ModifierFlags.Ambient) {
return updateTransformFlags(node, TransformFlags.None, TransformFlags.AssertTypeScript, TransformFlags.None);
}
let transformFlags = TransformFlags.None;
// If a VariableStatement is exported, then it is either ES6 or TypeScript syntax.
if (modifiers & ModifierFlags.Export) {
transformFlags = TransformFlags.AssertES6 | TransformFlags.AssertTypeScript;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function computeLabeledStatement(node: LabeledStatement, subtreeFlags: TransformFlags) {
let transformFlags = TransformFlags.None;
// A labeled statement containing a block scoped binding *may* need to be transformed from ES6.
if (subtreeFlags & TransformFlags.ContainsBlockScopedBinding
&& isIterationStatement(this, /*lookInLabeledStatements*/ true)) {
transformFlags = TransformFlags.AssertES6;
}
return updateTransformFlags(node, subtreeFlags, transformFlags, TransformFlags.None);
}
function updateTransformFlags(node: Node, subtreeFlags: TransformFlags, transformFlags: TransformFlags, excludeFlags: TransformFlags) {
node.transformFlags = transformFlags | subtreeFlags | TransformFlags.HasComputedFlags;
node.excludeTransformFlags = excludeFlags | TransformFlags.NodeExcludes;
return node.transformFlags & ~node.excludeTransformFlags;
}
}