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Fix comparable relation for keyof T

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Treat keyof T as string | number for purposes of indexing
Allow indexed access types with for-in and in operator
This commit is contained in:
Anders Hejlsberg 2016-11-19 09:03:23 -08:00
parent e81da9cd8a
commit dcd225a892
1 changed files with 12 additions and 8 deletions
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20
src/compiler/checker.ts
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@ -6037,11 +6037,12 @@ namespace ts {
const id = objectType.id + "," + indexType.id;
return indexedAccessTypes[id] || (indexedAccessTypes[id] = createIndexedAccessType(objectType, indexType));
}
const apparentType = getApparentType(objectType);
if (indexType.flags & TypeFlags.Union && !(indexType.flags & TypeFlags.Primitive)) {
const apparentObjectType = getApparentType(objectType);
const apparentIndexType = indexType.flags & TypeFlags.Index ? stringOrNumberType : indexType;
if (apparentIndexType.flags & TypeFlags.Union && !(apparentIndexType.flags & TypeFlags.Primitive)) {
const propTypes: Type[] = [];
for (const t of (<UnionType>indexType).types) {
const propType = getPropertyTypeForIndexType(apparentType, t, accessNode, /*cacheSymbol*/ false);
for (const t of (<UnionType>apparentIndexType).types) {
const propType = getPropertyTypeForIndexType(apparentObjectType, t, accessNode, /*cacheSymbol*/ false);
if (propType === unknownType) {
return unknownType;
}
@ -6049,7 +6050,7 @@ namespace ts {
}
return getUnionType(propTypes);
}
return getPropertyTypeForIndexType(apparentType, indexType, accessNode, /*cacheSymbol*/ true);
return getPropertyTypeForIndexType(apparentObjectType, apparentIndexType, accessNode, /*cacheSymbol*/ true);
}
function getTypeFromIndexedAccessTypeNode(node: IndexedAccessTypeNode) {
@ -7123,7 +7124,10 @@ namespace ts {
if (source.flags & TypeFlags.Index) {
// A keyof T is related to a union type containing both string and number
if (maybeTypeOfKind(target, TypeFlags.String) && maybeTypeOfKind(target, TypeFlags.Number)) {
const related = relation === comparableRelation ?
maybeTypeOfKind(target, TypeFlags.String | TypeFlags.Number) :
maybeTypeOfKind(target, TypeFlags.String) && maybeTypeOfKind(target, TypeFlags.Number);
if (related) {
return Ternary.True;
}
}
@ -14254,7 +14258,7 @@ namespace ts {
if (!isTypeAnyOrAllConstituentTypesHaveKind(leftType, TypeFlags.StringLike | TypeFlags.NumberLike | TypeFlags.ESSymbol)) {
error(left, Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
}
if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter)) {
if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter | TypeFlags.IndexedAccess)) {
error(right, Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
}
return booleanType;
@ -17148,7 +17152,7 @@ namespace ts {
const rightType = checkNonNullExpression(node.expression);
// unknownType is returned i.e. if node.expression is identifier whose name cannot be resolved
// in this case error about missing name is already reported - do not report extra one
if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter)) {
if (!isTypeAnyOrAllConstituentTypesHaveKind(rightType, TypeFlags.Object | TypeFlags.TypeParameter | TypeFlags.IndexedAccess)) {
error(node.expression, Diagnostics.The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter);
}