Minor refactor in goToTypeDefinition (microsoft#25951)

Andy · web-flow · commit f12e9a83890a · 2018-07-25T17:10:06.000-07:00
diff --git a/src/services/goToDefinition.ts b/src/services/goToDefinition.ts
@@ -136,15 +136,8 @@ namespace ts.GoToDefinition {
 
         const symbol = typeChecker.getSymbolAtLocation(node);
         const type = symbol && typeChecker.getTypeOfSymbolAtLocation(symbol, node);
-        if (!type) {
-            return undefined;
-        }
-
-        if (type.isUnion() && !(type.flags & TypeFlags.Enum)) {
-            return flatMap(type.types, t => t.symbol && getDefinitionFromSymbol(typeChecker, t.symbol, node));
-        }
-
-        return type.symbol && getDefinitionFromSymbol(typeChecker, type.symbol, node);
+        return type && flatMap(type.isUnion() && !(type.flags & TypeFlags.Enum) ? type.types : [type], t =>
+            t.symbol && getDefinitionFromSymbol(typeChecker, t.symbol, node));
     }
 
     export function getDefinitionAndBoundSpan(program: Program, sourceFile: SourceFile, position: number): DefinitionInfoAndBoundSpan | undefined {
@@ -230,7 +223,7 @@ namespace ts.GoToDefinition {
         }
 
         function getCallSignatureDefinition(): DefinitionInfo[] | undefined {
-            return isCallExpressionTarget(node) || isNewExpressionTarget(node) || isNameOfFunctionDeclaration(node)
+            return isCallOrNewExpressionTarget(node) || isNameOfFunctionDeclaration(node)
                 ? getSignatureDefinition(symbol.declarations, /*selectConstructors*/ false)
                 : undefined;
         }
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
@@ -194,16 +194,20 @@ namespace ts {
     }
 
     export function isCallExpressionTarget(node: Node): boolean {
-        return isCallOrNewExpressionTarget(node, SyntaxKind.CallExpression);
+        return isCallOrNewExpressionTargetWorker(node, isCallExpression);
     }
 
     export function isNewExpressionTarget(node: Node): boolean {
-        return isCallOrNewExpressionTarget(node, SyntaxKind.NewExpression);
+        return isCallOrNewExpressionTargetWorker(node, isNewExpression);
     }
 
-    function isCallOrNewExpressionTarget(node: Node, kind: SyntaxKind): boolean {
+    export function isCallOrNewExpressionTarget(node: Node): boolean {
+        return isCallOrNewExpressionTargetWorker(node, isCallOrNewExpression);
+    }
+
+    function isCallOrNewExpressionTargetWorker<T extends CallExpression | NewExpression>(node: Node, pred: (node: Node) => node is T): boolean {
         const target = climbPastPropertyAccess(node);
-        return !!target && !!target.parent && target.parent.kind === kind && (<CallExpression>target.parent).expression === target;
+        return !!target && !!target.parent && pred(target.parent) && target.parent.expression === target;
     }
 
     export function climbPastPropertyAccess(node: Node) {

Original file line number	Diff line number	Diff line change
`@@ -194,16 +194,20 @@ namespace ts {`
`194`	`194`	`}`
`195`	`195`
`196`	`196`	`export function isCallExpressionTarget(node: Node): boolean {`
`197`		`- return isCallOrNewExpressionTarget(node, SyntaxKind.CallExpression);`
	`197`	`+ return isCallOrNewExpressionTargetWorker(node, isCallExpression);`
`198`	`198`	`}`
`199`	`199`
`200`	`200`	`export function isNewExpressionTarget(node: Node): boolean {`
`201`		`- return isCallOrNewExpressionTarget(node, SyntaxKind.NewExpression);`
	`201`	`+ return isCallOrNewExpressionTargetWorker(node, isNewExpression);`
`202`	`202`	`}`
`203`	`203`
`204`		`- function isCallOrNewExpressionTarget(node: Node, kind: SyntaxKind): boolean {`
	`204`	`+ export function isCallOrNewExpressionTarget(node: Node): boolean {`
	`205`	`+ return isCallOrNewExpressionTargetWorker(node, isCallOrNewExpression);`
	`206`	`+ }`
	`207`	`+`
	`208`	`+ function isCallOrNewExpressionTargetWorker<T extends CallExpression \| NewExpression>(node: Node, pred: (node: Node) => node is T): boolean {`
`205`	`209`	`const target = climbPastPropertyAccess(node);`
`206`		`- return !!target && !!target.parent && target.parent.kind === kind && (<CallExpression>target.parent).expression === target;`
	`210`	`+ return !!target && !!target.parent && pred(target.parent) && target.parent.expression === target;`
`207`	`211`	`}`
`208`	`212`
`209`	`213`	`export function climbPastPropertyAccess(node: Node) {`