microsoft/TypeScript
1
0
Fork 0
mirror of https://github.com/microsoft/TypeScript.git synced 2026-05-23 17:30:04 -05:00
Code Issues Packages Projects Releases 212 Wiki Activity

Reject return type inferences to the autoType or autoArrayType (#27169)

Browse Source 
* Reject return type inferences to the autoType or autoArrayType

* Accept new error positions
This commit is contained in:
Wesley Wigham
2018-10-22 16:44:32 -07:00
committed by GitHub
parent 0c36266706
commit 6e5e09cef8
6 changed files with 249 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
src/compiler/checker.ts
View File

@@ -13665,7 +13665,7 @@ namespace ts {
// not contain anyFunctionType when we come back to this argument for its second round
// of inference. Also, we exclude inferences for silentNeverType (which is used as a wildcard
// when constructing types from type parameters that had no inference candidates).
if (source.flags & TypeFlags.ContainsAnyFunctionType || source === silentNeverType) {
if (source.flags & TypeFlags.ContainsAnyFunctionType || source === silentNeverType || (priority & InferencePriority.ReturnType && (source === autoType || source === autoArrayType))) {
return;
}
const inference = getInferenceInfoForType(target);
@@ -14904,7 +14904,7 @@ namespace ts {
// we give type 'any[]' to 'x' instead of using the type determined by control flow analysis such that operations
// on empty arrays are possible without implicit any errors and new element types can be inferred without
// type mismatch errors.
const resultType = getObjectFlags(evolvedType) & ObjectFlags.EvolvingArray && isEvolvingArrayOperationTarget(reference) ? anyArrayType : finalizeEvolvingArrayType(evolvedType);
const resultType = getObjectFlags(evolvedType) & ObjectFlags.EvolvingArray && isEvolvingArrayOperationTarget(reference) ? autoArrayType : finalizeEvolvingArrayType(evolvedType);
if (reference.parent && reference.parent.kind === SyntaxKind.NonNullExpression && getTypeWithFacts(resultType, TypeFacts.NEUndefinedOrNull).flags & TypeFlags.Never) {
return declaredType;
}
@@ -15895,7 +15895,7 @@ namespace ts {
// A variable is considered uninitialized when it is possible to analyze the entire control flow graph
// from declaration to use, and when the variable's declared type doesn't include undefined but the
// control flow based type does include undefined.
if (type === autoType || type === autoArrayType) {
if (!isEvolvingArrayOperationTarget(node) && (type === autoType || type === autoArrayType)) {
if (flowType === autoType || flowType === autoArrayType) {
if (noImplicitAny) {
error(getNameOfDeclaration(declaration), Diagnostics.Variable_0_implicitly_has_type_1_in_some_locations_where_its_type_cannot_be_determined, symbolToString(symbol), typeToString(flowType));