[BUGFIX] Ensure ArrayMixin#invoke returns an Ember.A.

packages/ember-runtime/lib/mixins/array.js

@@ -951,7 +951,11 @@ const ArrayMixin = Mixin.create(Enumerable, {
     @public
   */
   invoke(methodName, ...args) {
-    return this.map(item => tryInvoke(item, methodName, args));
+    let ret = A();
+
+    this.forEach(item => ret.push(tryInvoke(item, methodName, args)));
+
+    return ret;
   },
 
   /**

packages/ember-runtime/tests/array/invoke-test.js

@@ -1,4 +1,4 @@
-import EmberObject from '../../lib/system/object';
+import { Object as EmberObject, NativeArray } from '../../index';
 import { AbstractTestCase } from 'internal-test-helpers';
 import { runArrayTests } from '../helpers/array';
 
@@ -28,6 +28,33 @@ class InvokeTests extends AbstractTestCase {
     obj.invoke('foo', 2);
     this.assert.equal(cnt, 6, 'should have invoked 3 times, passing param');
   }
+
+  '@test invoke should return an array containing the results of each invoked method'(assert) {
+    let obj = this.newObject([
+      {
+        foo() {
+          return 'one';
+        },
+      },
+      {}, // intentionally not including `foo` method
+      {
+        foo() {
+          return 'two';
+        },
+      },
+    ]);
+
+    let result = obj.invoke('foo');
+    assert.deepEqual(result, ['one', undefined, 'two']);
+  }
+
+  '@test invoke should return an extended array (aka Ember.A)'(assert) {
+    let obj = this.newObject([{ foo() {} }, { foo() {} }]);
+
+    let result = obj.invoke('foo');
+
+    assert.ok(NativeArray.detect(result), 'NativeArray has been applied');
+  }
 }
 
 runArrayTests('invoke', InvokeTests);