microsoft/TypeScript
1
0
Fork 0
mirror of https://github.com/microsoft/TypeScript.git synced 2026-02-15 20:25:23 -06:00
Code Issues Packages Projects Releases 212 Wiki Activity

Consider null, undefined, and void to be unit types in type guards

Browse Source
This commit is contained in:
Anders Hejlsberg 2016-06-28 18:04:44 -07:00
parent e14fe5b830
commit 70e2c43d28
1 changed files with 18 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
src/compiler/checker.ts
View File

@ -6865,19 +6865,16 @@ namespace ts {
type.flags & TypeFlags.Enum && type.symbol.flags & SymbolFlags.EnumMember ? true : false;
}
function isLiteralUnionType(type: Type): boolean {
return type.flags & TypeFlags.Literal ? true :
type.flags & TypeFlags.Enum ? (type.symbol.flags & SymbolFlags.EnumMember) !== 0 :
type.flags & TypeFlags.Union ? forEach((<UnionType>type).types, isLiteralUnionType) :
false;
function isUnitUnionType(type: Type): boolean {
return type.flags & TypeFlags.Union ? forEach((<UnionType>type).types, isUnitType) : isUnitType(type);
}
function getBaseTypeOfLiteralType(type: Type): Type {
function getBaseTypeOfUnitType(type: Type): Type {
return type.flags & TypeFlags.StringLiteral ? stringType :
type.flags & TypeFlags.NumberLiteral ? numberType :
type.flags & TypeFlags.BooleanLiteral ? booleanType :
type.flags & TypeFlags.Enum && type.symbol.flags & SymbolFlags.EnumMember ? getDeclaredTypeOfSymbol(getParentOfSymbol(type.symbol)) :
type.flags & TypeFlags.Union ? getUnionType(map((<UnionType>type).types, getBaseTypeOfLiteralType)) :
type.flags & TypeFlags.Union ? getUnionType(map((<UnionType>type).types, getBaseTypeOfUnitType)) :
type;
}
@ -8123,7 +8120,7 @@ namespace ts {
}
function narrowTypeBySwitchOnDiscriminant(type: Type, switchStatement: SwitchStatement, clauseStart: number, clauseEnd: number) {
if (!isLiteralUnionType(type)) {
if (!isUnitUnionType(type)) {
return type;
}
const switchTypes = getSwitchClauseTypes(switchStatement);
@ -11970,7 +11967,7 @@ namespace ts {
return false;
}
const type = checkExpression(node.expression);
if (!isLiteralUnionType(type)) {
if (!isUnitUnionType(type)) {
return false;
}
const switchTypes = getSwitchClauseTypes(node);
@ -12690,11 +12687,11 @@ namespace ts {
case SyntaxKind.ExclamationEqualsToken:
case SyntaxKind.EqualsEqualsEqualsToken:
case SyntaxKind.ExclamationEqualsEqualsToken:
const leftIsLiteral = isLiteralUnionType(leftType);
const rightIsLiteral = isLiteralUnionType(rightType);
if (!leftIsLiteral || !rightIsLiteral) {
leftType = leftIsLiteral ? getBaseTypeOfLiteralType(leftType) : leftType;
rightType = rightIsLiteral ? getBaseTypeOfLiteralType(rightType) : rightType;
const leftIsUnit = isUnitUnionType(leftType);
const rightIsUnit = isUnitUnionType(rightType);
if (!leftIsUnit || !rightIsUnit) {
leftType = leftIsUnit ? getBaseTypeOfUnitType(leftType) : leftType;
rightType = rightIsUnit ? getBaseTypeOfUnitType(rightType) : rightType;
}
if (!isTypeEqualityComparableTo(leftType, rightType) && !isTypeEqualityComparableTo(rightType, leftType)) {
reportOperatorError();
@ -12836,6 +12833,13 @@ namespace ts {
return getUnionType([type1, type2]);
}
function isLiteralUnionType(type: Type): boolean {
return type.flags & TypeFlags.Literal ? true :
type.flags & TypeFlags.Enum ? (type.symbol.flags & SymbolFlags.EnumMember) !== 0 :
type.flags & TypeFlags.Union ? forEach((<UnionType>type).types, isLiteralUnionType) :
false;
}
function isLiteralTypeContext(node: Expression) {
return isLiteralTypeLocation(node) || isLiteralUnionType(getContextualType(node) || unknownType);
}