microsoft/TypeScript
1
0
Fork 0
mirror of https://github.com/microsoft/TypeScript.git synced 2026-05-15 04:43:37 -05:00
Code Issues Packages Projects Releases 212 Wiki Activity

Properly generate 'infer T' declarations in typeToTypeNode

Browse Source
This commit is contained in:
Anders Hejlsberg
2018-03-21 10:01:30 -07:00
parent 6a86534d81
commit fbd50487a5
1 changed files with 11 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
src/compiler/checker.ts
View File

@@ -2895,7 +2895,8 @@ namespace ts {
flags,
tracker: tracker && tracker.trackSymbol ? tracker : { trackSymbol: noop },
encounteredError: false,
symbolStack: undefined
symbolStack: undefined,
inferTypeParameters: undefined
};
}
@@ -2987,6 +2988,9 @@ namespace ts {
return typeReferenceToTypeNode(<TypeReference>type);
}
if (type.flags & TypeFlags.TypeParameter || objectFlags & ObjectFlags.ClassOrInterface) {
if (type.flags & TypeFlags.TypeParameter && contains(context.inferTypeParameters, type)) {
return createInferTypeNode(createTypeParameterDeclaration(getNameOfSymbolAsWritten(type.symbol)));
}
const name = type.symbol ? symbolToName(type.symbol, context, SymbolFlags.Type, /*expectsIdentifier*/ false) : createIdentifier("?");
// Ignore constraint/default when creating a usage (as opposed to declaration) of a type parameter.
return createTypeReferenceNode(name, /*typeArguments*/ undefined);
@@ -3027,7 +3031,10 @@ namespace ts {
}
if (type.flags & TypeFlags.Conditional) {
const checkTypeNode = typeToTypeNodeHelper((<ConditionalType>type).checkType, context);
const saveInferTypeParameters = context.inferTypeParameters;
context.inferTypeParameters = (<ConditionalType>type).root.inferTypeParameters;
const extendsTypeNode = typeToTypeNodeHelper((<ConditionalType>type).extendsType, context);
context.inferTypeParameters = saveInferTypeParameters;
const trueTypeNode = typeToTypeNodeHelper(getTrueTypeFromConditionalType(<ConditionalType>type), context);
const falseTypeNode = typeToTypeNodeHelper(getFalseTypeFromConditionalType(<ConditionalType>type), context);
return createConditionalTypeNode(checkTypeNode, extendsTypeNode, trueTypeNode, falseTypeNode);
@@ -3692,6 +3699,7 @@ namespace ts {
// State
encounteredError: boolean;
symbolStack: Symbol[] | undefined;
inferTypeParameters: TypeParameter[] | undefined;
}
function isDefaultBindingContext(location: Node) {
@@ -20597,7 +20605,8 @@ namespace ts {
}
function checkInferType(node: InferTypeNode) {
if (!findAncestor(node, n => n.parent && n.parent.kind === SyntaxKind.ConditionalType && (<ConditionalTypeNode>n.parent).extendsType === n)) {
const ancestor = findAncestor(node, n => n.parent && n.parent.kind === SyntaxKind.ConditionalType);
if (!ancestor || (<ConditionalTypeNode>ancestor.parent).extendsType !== ancestor) {
grammarErrorOnNode(node, Diagnostics.infer_declarations_are_only_permitted_in_the_extends_clause_of_a_conditional_type);
}
checkSourceElement(node.typeParameter);