Clean up helpers

src/compiler/core.ts

@@ -66,7 +66,6 @@ namespace ts {
 
     /** Methods on native maps but not on shim maps. Only used in this file. */
     interface ES6Map<T> extends Map<T> {
-        readonly size: number;
         entries(): Iterator<[string, T]>;
     }
 
@@ -130,6 +129,14 @@ namespace ts {
                 return !this.some(() => true);
             }
 
+            get size(): number {
+                let size = 0;
+                for (const _ in this.data) {
+                    size++;
+                }
+                return size;
+            }
+
             forEachInMap<U>(callback: (value: T, key: string) => U | undefined): U | undefined {
                 for (const key in this.data) {
                     const result = callback(this.data[key], key);
@@ -988,20 +995,6 @@ namespace ts {
         return true;
     }
 
-    /** True if the maps have the same keys and values. */
-    export function mapsAreEqual<T>(left: Map<T>, right: Map<T>, valuesAreEqual?: (left: T, right: T) => boolean): boolean {
-        if (left === right) return true;
-        if (!left || !right) return false;
-        const someInLeftHasNoMatch = someInMap(left, (leftValue, leftKey) => {
-            if (!right.has(leftKey)) return true;
-            const rightValue = right.get(leftKey);
-            return !(valuesAreEqual ? valuesAreEqual(leftValue, rightValue) : leftValue === rightValue);
-        });
-        if (someInLeftHasNoMatch) return false;
-        const someInRightHasNoMatch = someKeyInMap(right, rightKey => !left.has(rightKey));
-        return !someInRightHasNoMatch;
-    }
-
     /**
      * Creates a map from the elements of an array.
      *

src/compiler/types.ts

@@ -20,6 +20,7 @@ namespace ts {
         clear(): void;
         /** `key` may *not* be a string if it was set with a number and we are not using the shim. */
         forEach(action: (value: T, key: string) => void): void;
+        readonly size: number;
     }
 
     // branded string type used to store absolute, normalized and canonicalized paths

src/harness/unittests/reuseProgramStructure.ts

@@ -193,6 +193,20 @@ namespace ts {
         }
     }
 
+    /** True if the maps have the same keys and values. */
+    function mapsAreEqual<T>(left: Map<T>, right: Map<T>, valuesAreEqual?: (left: T, right: T) => boolean): boolean {
+        if (left === right) return true;
+        if (!left || !right) return false;
+        const someInLeftHasNoMatch = someInMap(left, (leftValue, leftKey) => {
+            if (!right.has(leftKey)) return true;
+            const rightValue = right.get(leftKey);
+            return !(valuesAreEqual ? valuesAreEqual(leftValue, rightValue) : leftValue === rightValue);
+        });
+        if (someInLeftHasNoMatch) return false;
+        const someInRightHasNoMatch = someKeyInMap(right, rightKey => !left.has(rightKey));
+        return !someInRightHasNoMatch;
+    }
+
     function checkResolvedModulesCache(program: Program, fileName: string, expectedContent: Map<ResolvedModule>): void {
         checkCache("resolved modules", program, fileName, expectedContent, f => f.resolvedModules, checkResolvedModule);
     }

src/harness/unittests/tsserverProjectSystem.ts

@@ -243,18 +243,12 @@ namespace ts.projectSystem {
     }
 
     export function checkMapKeys(caption: string, map: Map<any>, expectedKeys: string[]) {
-        assert.equal(mapSize(map), expectedKeys.length, `${caption}: incorrect size of map`);
+        assert.equal(map.size, expectedKeys.length, `${caption}: incorrect size of map`);
         for (const name of expectedKeys) {
             assert.isTrue(map.has(name), `${caption} is expected to contain ${name}, actual keys: ${keysOfMap(map)}`);
         }
     }
 
-    function mapSize<T>(map: Map<T>): number {
-        let size = 0;
-        map.forEach(() => { size++; });
-        return size;
-    }
-
     export function checkFileNames(caption: string, actualFileNames: string[], expectedFileNames: string[]) {
         assert.equal(actualFileNames.length, expectedFileNames.length, `${caption}: incorrect actual number of files, expected ${JSON.stringify(expectedFileNames)}, got ${actualFileNames}`);
         for (const f of expectedFileNames) {
@@ -313,7 +307,7 @@ namespace ts.projectSystem {
         }
 
         count() {
-            return mapSize(this.map);
+            return this.map.size;
         }
 
         invoke() {