microsoft/TypeScript
1
0
Fork 0
mirror of https://github.com/microsoft/TypeScript.git synced 2026-02-15 03:23:08 -06:00
Code Issues Packages Projects Releases 212 Wiki Activity

Obtain constraint from destructured property when applicable

Browse Source
This commit is contained in:
Anders Hejlsberg 2018-03-23 09:42:43 -07:00
parent 02ee11c357
commit deb87bb8ad
1 changed files with 3 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
src/compiler/checker.ts
View File

@ -4082,8 +4082,7 @@ namespace ts {
if (strictNullChecks && declaration.flags & NodeFlags.Ambient && isParameterDeclaration(declaration)) {
parentType = getNonNullableType(parentType);
}
const propType = getTypeOfPropertyOfType(parentType, text);
const declaredType = propType && getConstraintForLocation(propType, declaration.name);
const declaredType = getConstraintForLocation(getTypeOfPropertyOfType(parentType, text), declaration.name);
type = declaredType && getFlowTypeOfReference(declaration, declaredType) ||
isNumericLiteralName(text) && getIndexTypeOfType(parentType, IndexKind.Number) ||
getIndexTypeOfType(parentType, IndexKind.String);
@ -12382,7 +12381,7 @@ namespace ts {
function getTypeOfDestructuredProperty(type: Type, name: PropertyName) {
const text = getTextOfPropertyName(name);
return getTypeOfPropertyOfType(type, text) ||
return getConstraintForLocation(getTypeOfPropertyOfType(type, text), name) ||
isNumericLiteralName(text) && getIndexTypeOfType(type, IndexKind.Number) ||
getIndexTypeOfType(type, IndexKind.String) ||
unknownType;
@ -13498,7 +13497,7 @@ namespace ts {
// and the type of the node includes type variables with constraints that are nullable, we fetch the
// apparent type of the node *before* performing control flow analysis such that narrowings apply to
// the constraint type.
if (isConstraintPosition(node) && forEachType(type, typeHasNullableConstraint)) {
if (type && isConstraintPosition(node) && forEachType(type, typeHasNullableConstraint)) {
return mapType(getWidenedType(type), getBaseConstraintOrType);
}
return type;