Merge pull request microsoft#17079 from Microsoft/noTypeArgsSum

DanielRosenwasser · web-flow · commit 38f6db52ac30 · 2017-07-12T00:09:58.000-07:00
Declare 'sum' so that it doesn't require type arguments.
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -83,9 +83,9 @@ namespace ts {
         // extra cost of calling `getParseTreeNode` when calling these functions from inside the
         // checker.
         const checker: TypeChecker = {
-            getNodeCount: () => sum<"nodeCount">(host.getSourceFiles(), "nodeCount"),
-            getIdentifierCount: () => sum<"identifierCount">(host.getSourceFiles(), "identifierCount"),
-            getSymbolCount: () => sum<"symbolCount">(host.getSourceFiles(), "symbolCount") + symbolCount,
+            getNodeCount: () => sum(host.getSourceFiles(), "nodeCount"),
+            getIdentifierCount: () => sum(host.getSourceFiles(), "identifierCount"),
+            getSymbolCount: () => sum(host.getSourceFiles(), "symbolCount") + symbolCount,
             getTypeCount: () => typeCount,
             isUndefinedSymbol: symbol => symbol === undefinedSymbol,
             isArgumentsSymbol: symbol => symbol === argumentsSymbol,
diff --git a/src/compiler/core.ts b/src/compiler/core.ts
@@ -710,10 +710,11 @@ namespace ts {
         return result;
     }
 
-    export function sum<K extends string>(array: { [x in K]: number }[], prop: K): number {
+    export function sum<T extends Record<K, number>, K extends string>(array: T[], prop: K): number {
         let result = 0;
         for (const v of array) {
-            result += v[prop];
+            // Note: we need the following type assertion because of GH #17069
+            result += v[prop] as number;
         }
         return result;
     }

Original file line number	Diff line number	Diff line change
`@@ -710,10 +710,11 @@ namespace ts {`
`710`	`710`	`return result;`
`711`	`711`	`}`
`712`	`712`
`713`		`- export function sum<K extends string>(array: { [x in K]: number }[], prop: K): number {`
	`713`	`+ export function sum<T extends Record<K, number>, K extends string>(array: T[], prop: K): number {`
`714`	`714`	`let result = 0;`
`715`	`715`	`for (const v of array) {`
`716`		`- result += v[prop];`
	`716`	`+ // Note: we need the following type assertion because of GH #17069`
	`717`	`+ result += v[prop] as number;`
`717`	`718`	`}`
`718`	`719`	`return result;`
`719`	`720`	`}`