More simplification + consistent use of getConstraintOfTypeParameter

ahejlsberg · ahejlsberg · commit 1fd1de962561 · 2018-07-24T15:27:39.000-07:00
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -249,7 +249,7 @@ namespace ts {
                 getTypeOfSymbol,
                 getResolvedSymbol,
                 getIndexTypeOfStructuredType,
-                getConstraintFromTypeParameter,
+                getConstraintOfTypeParameter,
                 getFirstIdentifier,
             ),
             getAmbientModules,
@@ -6951,21 +6951,12 @@ namespace ts {
             return undefined;
         }
 
-        function getBaseConstraintOfInstantiableNonPrimitiveUnionOrIntersection(type: Type) {
+        function getBaseConstraintOfType(type: Type): Type | undefined {
             if (type.flags & (TypeFlags.InstantiableNonPrimitive | TypeFlags.UnionOrIntersection)) {
                 const constraint = getResolvedBaseConstraint(<InstantiableType | UnionOrIntersectionType>type);
-                if (constraint !== noConstraintType && constraint !== circularConstraintType) {
-                    return constraint;
-                }
-            }
-        }
-
-        function getBaseConstraintOfType(type: Type): Type | undefined {
-            const constraint = getBaseConstraintOfInstantiableNonPrimitiveUnionOrIntersection(type);
-            if (!constraint && type.flags & TypeFlags.Index) {
-                return keyofConstraintType;
+                return constraint !== noConstraintType && constraint !== circularConstraintType ? constraint : undefined;
             }
-            return constraint;
+            return type.flags & TypeFlags.Index ? keyofConstraintType : undefined;
         }
 
         /**
diff --git a/src/compiler/symbolWalker.ts b/src/compiler/symbolWalker.ts
@@ -9,7 +9,7 @@ namespace ts {
         getTypeOfSymbol: (sym: Symbol) => Type,
         getResolvedSymbol: (node: Node) => Symbol,
         getIndexTypeOfStructuredType: (type: Type, kind: IndexKind) => Type | undefined,
-        getConstraintFromTypeParameter: (typeParameter: TypeParameter) => Type | undefined,
+        getConstraintOfTypeParameter: (typeParameter: TypeParameter) => Type | undefined,
         getFirstIdentifier: (node: EntityNameOrEntityNameExpression) => Identifier) {
 
         return getSymbolWalker;
@@ -93,7 +93,7 @@ namespace ts {
             }
 
             function visitTypeParameter(type: TypeParameter): void {
-                visitType(getConstraintFromTypeParameter(type));
+                visitType(getConstraintOfTypeParameter(type));
             }
 
             function visitUnionOrIntersectionType(type: UnionOrIntersectionType): void {

Original file line number	Diff line number	Diff line change
`@@ -9,7 +9,7 @@ namespace ts {`
`9`	`9`	`getTypeOfSymbol: (sym: Symbol) => Type,`
`10`	`10`	`getResolvedSymbol: (node: Node) => Symbol,`
`11`	`11`	`getIndexTypeOfStructuredType: (type: Type, kind: IndexKind) => Type \| undefined,`
`12`		`- getConstraintFromTypeParameter: (typeParameter: TypeParameter) => Type \| undefined,`
	`12`	`+ getConstraintOfTypeParameter: (typeParameter: TypeParameter) => Type \| undefined,`
`13`	`13`	`getFirstIdentifier: (node: EntityNameOrEntityNameExpression) => Identifier) {`
`14`	`14`
`15`	`15`	`return getSymbolWalker;`
`@@ -93,7 +93,7 @@ namespace ts {`
`93`	`93`	`}`
`94`	`94`
`95`	`95`	`function visitTypeParameter(type: TypeParameter): void {`
`96`		`- visitType(getConstraintFromTypeParameter(type));`
	`96`	`+ visitType(getConstraintOfTypeParameter(type));`
`97`	`97`	`}`
`98`	`98`
`99`	`99`	`function visitUnionOrIntersectionType(type: UnionOrIntersectionType): void {`