Auto merge of #15002 - emberjs:empty-object, r=stefanpenner

[Fixes #15001] Remove internal EmptyObject usage

- [x] confirm all are correctly removed
- [x] confirm tests pass
- [ ] do some tests

----

If this ends up good, we should likely consider deprecating `Ember.EmptyObject`.

---

cc @bmeurer

packages/container/lib/registry.js

@@ -1,4 +1,4 @@
-import { dictionary, EmptyObject, assign, intern } from 'ember-utils';
+import { dictionary, assign, intern } from 'ember-utils';
 import { assert, deprecate } from 'ember-metal';
 import Container from './container';
 
@@ -35,7 +35,7 @@ export default function Registry(options) {
   this._factoryTypeInjections = dictionary(null);
   this._factoryInjections     = dictionary(null);
 
-  this._localLookupCache      = new EmptyObject();
+  this._localLookupCache      = Object.create(null);
   this._normalizeCache        = dictionary(null);
   this._resolveCache          = dictionary(null);
   this._failCache             = dictionary(null);
@@ -205,7 +205,7 @@ Registry.prototype = {
 
     let normalizedName = this.normalize(fullName);
 
-    this._localLookupCache = new EmptyObject();
+    this._localLookupCache = Object.create(null);
 
     delete this.registrations[normalizedName];
     delete this._resolveCache[normalizedName];
@@ -811,7 +811,7 @@ function expandLocalLookup(registry, normalizedName, normalizedSource) {
   let normalizedNameCache = cache[normalizedName];
 
   if (!normalizedNameCache) {
-    normalizedNameCache = cache[normalizedName] = new EmptyObject();
+    normalizedNameCache = cache[normalizedName] = Object.create(null);
   }
 
   let cached = normalizedNameCache[normalizedSource];

packages/ember-application/lib/system/engine.js

@@ -2,7 +2,7 @@
 @module ember
 @submodule ember-application
 */
-import { canInvoke, EmptyObject } from 'ember-utils';
+import { canInvoke } from 'ember-utils';
 import {
   Namespace,
   RegistryProxyMixin,
@@ -168,8 +168,8 @@ const Engine = Namespace.extend(RegistryProxyMixin, {
 });
 
 Engine.reopenClass({
-  initializers: new EmptyObject(),
-  instanceInitializers: new EmptyObject(),
+  initializers: Object.create(null),
+  instanceInitializers: Object.create(null),
 
   /**
     The goal of initializers should be to register dependencies and injections.

packages/ember-glimmer/lib/components/text_field.js

@@ -2,15 +2,14 @@
 @module ember
 @submodule ember-views
 */
-import { EmptyObject } from 'ember-utils';
 import { computed } from 'ember-metal';
 import { environment } from 'ember-environment';
 import Component from '../component';
 import layout from '../templates/empty';
 import { TextSupport } from 'ember-views';
 
 let inputTypeTestElement;
-const inputTypes = new EmptyObject();
+const inputTypes = Object.create(null);
 function canSetTypeOfInput(type) {
   if (type in inputTypes) {
     return inputTypes[type];

packages/ember-glimmer/lib/utils/iterable.js

@@ -1,4 +1,4 @@
-import { guidFor, EmptyObject } from 'ember-utils';
+import { guidFor } from 'ember-utils';
 import { get, tagForProperty, tagFor, isProxy } from 'ember-metal';
 import {
   objectAt,
@@ -84,7 +84,7 @@ class ArrayIterator {
     this.length = array.length;
     this.keyFor = keyFor;
     this.position = 0;
-    this.seen = new EmptyObject();
+    this.seen = Object.create(null);
   }
 
   isEmpty() {
@@ -112,7 +112,7 @@ class EmberArrayIterator {
     this.length = get(array, 'length');
     this.keyFor = keyFor;
     this.position = 0;
-    this.seen = new EmptyObject();
+    this.seen = Object.create(null);
   }
 
   isEmpty() {
@@ -140,7 +140,7 @@ class ObjectKeysIterator {
     this.values = values;
     this.keyFor = keyFor;
     this.position = 0;
-    this.seen = new EmptyObject();
+    this.seen = Object.create(null);
   }
 
   isEmpty() {

packages/ember-glimmer/lib/utils/process-args.js

@@ -1,7 +1,6 @@
 import {
   assign,
-  symbol,
-  EmptyObject
+  symbol
 } from 'ember-utils';
 import {
   CONSTANT_TAG
@@ -88,8 +87,8 @@ export class ComponentArgs {
     let { namedArgs } = this;
     let keys = namedArgs.keys;
     let attrs = namedArgs.value();
-    let props = new EmptyObject();
-    let args = new EmptyObject();
+    let props = Object.create(null);
+    let args = Object.create(null);
 
     props[ARGS] = args;
 

packages/ember-glimmer/lib/utils/references.js

@@ -1,7 +1,6 @@
 import {
   HAS_NATIVE_WEAKMAP,
-  symbol,
-  EmptyObject
+  symbol
 } from 'ember-utils';
 import {
   get,
@@ -72,7 +71,7 @@ export class CachedReference extends EmberPathReference {
 export class RootReference extends ConstReference {
   constructor(value) {
     super(value);
-    this.children = new EmptyObject();
+    this.children = Object.create(null);
   }
 
   get(propertyKey) {

packages/ember-glimmer/lib/views/outlet.js

@@ -2,7 +2,7 @@
 @module ember
 @submodule ember-glimmer
 */
-import { assign, EmptyObject } from 'ember-utils';
+import { assign } from 'ember-utils';
 import { DirtyableTag } from '@glimmer/reference';
 import { environment } from 'ember-environment';
 import { OWNER } from 'ember-utils';
@@ -56,7 +56,7 @@ class OrphanedOutletStateReference extends OutletStateReference {
       return null;
     }
 
-    let state = new EmptyObject();
+    let state = Object.create(null);
     state[matched.render.outlet] = matched;
     matched.wasUsed = true;
     return { outlets: state };

packages/ember-glimmer/tests/unit/layout-cache-test.js

@@ -1,4 +1,3 @@
-import { EmptyObject } from 'ember-utils';
 import { RenderingTest, moduleFor } from '../utils/test-case';
 import { CompiledBlock } from '@glimmer/runtime';
 import { OWNER } from 'ember-utils';
@@ -19,7 +18,7 @@ class Counter {
 
   reset() {
     this.total  = 0;
-    this.counts = new EmptyObject();
+    this.counts = Object.create(null);
   }
 }
 

packages/ember-metal/lib/cache.js

@@ -1,4 +1,3 @@
-import { EmptyObject } from 'ember-utils';
 import { UNDEFINED } from './meta';
 
 export default class Cache {
@@ -57,7 +56,7 @@ export default class Cache {
 
 class DefaultStore {
   constructor() {
-    this.data = new EmptyObject();
+    this.data = Object.create(null);
   }
 
   get(key) {
@@ -69,6 +68,6 @@ class DefaultStore {
   }
 
   clear() {
-    this.data = new EmptyObject();
+    this.data = Object.create(null);
   }
 }

packages/ember-metal/lib/chains.js

@@ -1,4 +1,3 @@
-import { EmptyObject } from 'ember-utils';
 import { get } from './property_get';
 import { meta as metaFor, peekMeta } from './meta';
 import { watchKey, unwatchKey } from './watch_key';
@@ -23,7 +22,7 @@ class ChainWatchers {
     // chain nodes that reference a key in this obj by key
     // we only create ChainWatchers when we are going to add them
     // so create this upfront
-    this.chains = new EmptyObject();
+    this.chains = Object.create(null);
   }
 
   add(key, node) {
@@ -231,7 +230,7 @@ class ChainNode {
     let chains = this._chains;
     let node;
     if (chains === undefined) {
-      chains = this._chains = new EmptyObject();
+      chains = this._chains = Object.create(null);
     } else {
       node = chains[key];
     }

packages/ember-metal/lib/map.js

@@ -20,7 +20,7 @@
   Map is mocked out to look like an Ember object, so you can do
   `Ember.Map.create()` for symmetry with other Ember classes.
 */
-import { EmptyObject, guidFor } from 'ember-utils';
+import { guidFor } from 'ember-utils';
 
 function missingFunction(fn) {
   throw new TypeError(`${Object.prototype.toString.call(fn)} is not a function`);
@@ -31,10 +31,10 @@ function missingNew(name) {
 }
 
 function copyNull(obj) {
-  let output = new EmptyObject();
+  let output = Object.create(null);
 
   for (let prop in obj) {
-    // hasOwnPropery is not needed because obj is new EmptyObject();
+    // hasOwnPropery is not needed because obj is Object.create(null);
     output[prop] = obj[prop];
   }
 
@@ -90,7 +90,7 @@ OrderedSet.prototype = {
     @private
   */
   clear() {
-    this.presenceSet = new EmptyObject();
+    this.presenceSet = Object.create(null);
     this.list = [];
     this.size = 0;
   },
@@ -242,7 +242,7 @@ function Map() {
   if (this instanceof Map) {
     this._keys = OrderedSet.create();
     this._keys._silenceRemoveDeprecation = true;
-    this._values = new EmptyObject();
+    this._values = Object.create(null);
     this.size = 0;
   } else {
     missingNew('Map');
@@ -394,7 +394,7 @@ Map.prototype = {
   */
   clear() {
     this._keys.clear();
-    this._values = new EmptyObject();
+    this._values = Object.create(null);
     this.size = 0;
   },
 

packages/ember-metal/lib/meta.js

@@ -1,6 +1,5 @@
 import {
   HAS_NATIVE_WEAKMAP,
-  EmptyObject,
   lookupDescriptor,
   symbol
 } from 'ember-utils';
@@ -202,7 +201,7 @@ export class Meta {
   }
 
   _getOrCreateOwnMap(key) {
-    return this[key] || (this[key] = new EmptyObject());
+    return this[key] || (this[key] = Object.create(null));
   }
 
   _getInherited(key) {
@@ -238,7 +237,7 @@ export class Meta {
     let outerMap = this._getOrCreateOwnMap('_deps');
     let innerMap = outerMap[subkey];
     if (!innerMap) {
-      innerMap = outerMap[subkey] = new EmptyObject();
+      innerMap = outerMap[subkey] = Object.create(null);
     }
     innerMap[itemkey] = value;
   }
@@ -282,7 +281,7 @@ export class Meta {
     while (pointer !== undefined) {
       let map = pointer[key];
       if (map) {
-        seen = seen || new EmptyObject();
+        seen = seen || Object.create(null);
         let innerMap = map[subkey];
         if (innerMap) {
           for (let innerKey in innerMap) {
@@ -372,7 +371,7 @@ function inheritedMap(name, Meta) {
 
   Meta.prototype[`forEach${capitalized}`] = function(fn) {
     let pointer = this;
-    let seen = new EmptyObject();
+    let seen = Object.create(null);
     while (pointer !== undefined) {
       let map = pointer[key];
       if (map) {

packages/ember-routing/lib/system/cache.js

@@ -1,4 +1,3 @@
-import { EmptyObject } from 'ember-utils';
 import { Object as EmberObject } from 'ember-runtime';
 
 /**
@@ -10,7 +9,7 @@ import { Object as EmberObject } from 'ember-runtime';
 */
 export default EmberObject.extend({
   init() {
-    this.cache = new EmptyObject();
+    this.cache = Object.create(null);
   },
 
   has(bucketKey) {
@@ -21,7 +20,7 @@ export default EmberObject.extend({
     let bucket = this.cache[bucketKey];
 
     if (!bucket) {
-      bucket = this.cache[bucketKey] = new EmptyObject();
+      bucket = this.cache[bucketKey] = Object.create(null);
     }
 
     bucket[key] = value;

packages/ember-routing/lib/system/router.js

@@ -1,5 +1,4 @@
 import {
-  EmptyObject,
   assign,
   guidFor,
   dictionary,
@@ -144,11 +143,11 @@ const EmberRouter = EmberObject.extend(Evented, {
     this.currentRouteName = null;
     this.currentPath = null;
 
-    this._qpCache = new EmptyObject();
+    this._qpCache = Object.create(null);
     this._resetQueuedQueryParameterChanges();
     this._handledErrors = dictionary(null);
-    this._engineInstances = new EmptyObject();
-    this._engineInfoByRoute = new EmptyObject();
+    this._engineInstances = Object.create(null);
+    this._engineInfoByRoute = Object.create(null)
   },
 
   /*
@@ -571,7 +570,7 @@ const EmberRouter = EmberObject.extend(Evented, {
   },
 
   _getHandlerFunction() {
-    let seen = new EmptyObject();
+    let seen = Object.create(null);
     let owner = getOwner(this);
 
     return name => {
@@ -1024,7 +1023,7 @@ const EmberRouter = EmberObject.extend(Evented, {
     let engineInstances = this._engineInstances;
 
     if (!engineInstances[name]) {
-      engineInstances[name] = new EmptyObject();
+      engineInstances[name] = Object.create(null);
     }
 
     let engineInstance = engineInstances[name][instanceId];
@@ -1483,7 +1482,7 @@ function appendLiveRoute(liveRoutes, defaultParentState, renderOptions) {
   let target;
   let myState = {
     render: renderOptions,
-    outlets: new EmptyObject(),
+    outlets: Object.create(null),
     wasUsed: false
   };
   if (renderOptions.into) {
@@ -1528,7 +1527,7 @@ function appendOrphan(liveRoutes, into, myState) {
       render: {
         name: '__ember_orphans__'
       },
-      outlets: new EmptyObject()
+      outlets: Object.create(null)
     };
   }
   liveRoutes.outlets.__ember_orphans__.outlets[into] = myState;