Merge pull request #16526 from rwjblue/avoid-erroring-for-name-key

[BUGFIX beta] Ensure setting a `NAME_KEY` does not error.

packages/ember-metal/lib/mixin.js

@@ -2,7 +2,7 @@
 @module @ember/object
 */
 import { EMBER_METAL_ES5_GETTERS } from 'ember/features';
-import { assign, guidFor, ROOT, wrap, makeArray } from 'ember-utils';
+import { assign, guidFor, ROOT, wrap, makeArray, NAME_KEY } from 'ember-utils';
 import { assert } from 'ember-debug';
 import { DEBUG } from 'ember-env-flags';
 import { ENV } from 'ember-environment';
@@ -449,6 +449,7 @@ export default class Mixin {
     this._without = undefined;
 
     if (DEBUG) {
+      this[NAME_KEY] = undefined;
       /*
         In debug builds, we seal mixins to help avoid performance pitfalls.
 
@@ -609,6 +610,7 @@ if (ENV._ENABLE_BINDING_SUPPORT) {
 Mixin.prototype.toString = classToString;
 
 if (DEBUG) {
+  Mixin.prototype[NAME_KEY] = undefined;
   Object.seal(Mixin.prototype);
 }
 

packages/ember-metal/tests/mixin/introspection_test.js

@@ -2,7 +2,7 @@
 // as well as methods vs props.  We are just keeping these for testing; the
 // current impl doesn't care about the differences as much...
 
-import { guidFor } from 'ember-utils';
+import { guidFor, NAME_KEY } from 'ember-utils';
 import { mixin, Mixin } from '../..';
 import { moduleFor, AbstractTestCase } from 'internal-test-helpers';
 
@@ -58,5 +58,18 @@ moduleFor(
         'should return included mixins'
       );
     }
+
+    ['@test setting a NAME_KEY on a mixin does not error'](assert) {
+      assert.expect(0);
+
+      let instance = Mixin.create();
+      instance[NAME_KEY] = 'My special name!';
+    }
+
+    ['@test setting a NAME_KEY on a mixin instance does not error'](assert) {
+      assert.expect(0);
+
+      Mixin.create({ [NAME_KEY]: 'My special name' });
+    }
   }
 );