fix($injector): workaround for MS Edge class detection

Fix for MS Edge class detection

Closes: #13697

Author: lgalfaso

src/auto/injector.js

@@ -826,8 +826,10 @@ function createInjector(modulesToLoad, strictDi) {
       if (msie <= 11) {
         return false;
       }
+      // Workaround for MS Edge.
+      // Check https://connect.microsoft.com/IE/Feedback/Details/2211653
       return typeof func === 'function'
-        && /^class\s/.test(Function.prototype.toString.call(func));
+        && /^(?:class\s|constructor\()/.test(Function.prototype.toString.call(func));
     }
 
     function invoke(fn, self, locals, serviceName) {

test/auto/injectorSpec.js

@@ -1,5 +1,7 @@
 'use strict';
 
+/* globals support: false */
+
 describe('injector', function() {
   var providers;
   var injector;
@@ -247,42 +249,47 @@ describe('injector', function() {
     });
 
 
-    // Only Chrome and Firefox support this syntax.
-    if (/chrome|firefox/i.test(navigator.userAgent)) {
-      describe('es6', function() {
-        /*jshint -W061 */
+    describe('es6', function() {
+      /*jshint -W061 */
+      if (support.ES6Function) {
         // The functions are generated using `eval` as just having the ES6 syntax can break some browsers.
         it('should be possible to annotate functions that are declared using ES6 syntax', function() {
           expect(annotate(eval('({ fn(x) { return; } })').fn)).toEqual(['x']);
         });
+      }
 
 
+      if (support.fatArrow) {
         it('should create $inject for arrow functions', function() {
           expect(annotate(eval('(a, b) => a'))).toEqual(['a', 'b']);
         });
+      }
 
 
+      if (support.fatArrow) {
         it('should create $inject for arrow functions with no parenthesis', function() {
           expect(annotate(eval('a => a'))).toEqual(['a']);
         });
+      }
 
 
+      if (support.fatArrow) {
         it('should take args before first arrow', function() {
           expect(annotate(eval('a => b => b'))).toEqual(['a']);
         });
+      }
 
+      if (support.classes) {
         it('should be possible to instantiate ES6 classes', function() {
-          // Only Chrome (not even the FF we use) supports ES6 classes.
-          if (!/chrome/i.test(navigator.userAgent)) return;
           providers('a', function() { return 'a-value'; });
           var clazz = eval('(class { constructor(a) { this.a = a; } aVal() { return this.a; } })');
           var instance = injector.instantiate(clazz);
           expect(instance).toEqual({a: 'a-value'});
           expect(instance.aVal()).toEqual('a-value');
         });
-        /*jshint +W061 */
-      });
-    }
+      }
+      /*jshint +W061 */
+    });
 
 
     it('should publish annotate API', function() {

test/helpers/testabilityPatch.js

@@ -11,6 +11,28 @@ if (window._jQuery) _jQuery.event.special.change = undefined;
 
 if (window.bindJQuery) bindJQuery();
 
+var supportTests = {
+  classes: '(class {})',
+  fatArrow: 'a => a',
+  ES6Function: '({ fn(x) { return; } })'
+};
+
+var support = {};
+
+for (var prop in supportTests) {
+  if (supportTests.hasOwnProperty(prop)) {
+    /*jshint -W061 */
+    try {
+      eval(supportTests[prop]);
+      support[prop] = true;
+    } catch (e) {
+      support[prop] = false;
+    }
+    /*jshint +W061 */
+  }
+}
+
+
 beforeEach(function() {
 
   // all this stuff is not needed for module tests, where jqlite and publishExternalAPI and jqLite are not global vars