feat(lang): support const expressions in TS/JS and Dart

pkozlowski-opensource · pkozlowski-opensource · commit 4665726f48bc · 2015-05-11T12:11:24.000+02:00
Closes angular#1796
diff --git a/modules/angular2/src/facade/lang.ts b/modules/angular2/src/facade/lang.ts
@@ -40,6 +40,11 @@ if (assertionsEnabled_) {
 }
 export {int};
 
+// This function is needed only to properly support Dart's const expressions
+// see https://github.com/angular/ts2dart/pull/151 for more info
+export function CONST_EXPR<T>(expr: T): T {
+  return expr;
+};
 export function CONST() {
   return (target) => target;
 };
diff --git a/modules/angular2/test/facade/lang_spec.js b/modules/angular2/test/facade/lang_spec.js
@@ -1,7 +1,7 @@
 import {describe, it, expect, beforeEach, ddescribe, iit, xit, el} from 'angular2/test_lib';
 
 import {ListWrapper} from 'angular2/src/facade/collection';
-import {isPresent, RegExpWrapper, RegExpMatcherWrapper} from 'angular2/src/facade/lang';
+import {isPresent, RegExpWrapper, RegExpMatcherWrapper, CONST_EXPR} from 'angular2/src/facade/lang';
 
 export function main() {
   describe('RegExp', () => {
@@ -21,4 +21,12 @@ export function main() {
       expect(indexes).toEqual([1, 4, 8, 9]);
     })
  });
+
+  describe('const', () => {
+    it('should support const expressions both in TS and Dart', () => {
+      const numbers = CONST_EXPR([1, 2, 3]);
+      expect(numbers).toEqual([1, 2, 3]);
+    })
+ });
+
 }
