[BUGFIX beta] Use native Map if present.

.eslintrc.js

@@ -10,7 +10,8 @@ module.exports = {
     'browser': true,
   },
   globals: {
-    'heimdall': true
+    'heimdall': true,
+    'Map': false,
   },
   rules: {
     'no-unused-vars': ['error', {

addon/-private/index.js

@@ -48,6 +48,9 @@ export { default as ManyArray } from './system/many-array';
 export { default as RecordArrayManager } from './system/record-array-manager';
 export { default as Relationship } from './system/relationships/state/relationship';
 
+export { default as Map } from './system/map';
+export { default as MapWithDefault } from './system/map-with-default';
+
 // Should be a different Repo ?
 export { default as DebugAdapter } from './system/debug/debug-adapter';
 

addon/-private/system/map-with-default.js

@@ -0,0 +1,21 @@
+import Map from './map';
+
+export default class MapWithDefault extends Map {
+  constructor(options) {
+    super();
+
+    this.defaultValue = options.defaultValue;
+  }
+
+  get(key) {
+    let hasValue = this.has(key);
+
+    if (hasValue) {
+      return super.get(key);
+    } else {
+      let defaultValue = this.defaultValue(key);
+      this.set(key, defaultValue);
+      return defaultValue;
+    }
+  }
+}

addon/-private/system/map.js

@@ -0,0 +1,102 @@
+import { deprecate } from '@ember/debug';
+
+/*
+  ## Why does this exist?!?
+
+  `Ember.Map` was a private API provided by Ember (for quite some time).
+  Unfortunately, ember-data made `Ember.Map` part of its public API surface via
+  documentation blocks.
+
+  `Ember.Map` will be deprecated and removed from Ember "soon"
+  (https://github.com/emberjs/rfcs/pull/237) and we would like to confirm that
+  Ember Data will work without deprecation before and after that happens.
+
+  `Ember.Map` differs from native `Map` in a few ways:
+
+  * `Ember.Map` has custom `copy` and `isEmpty` methods which are not present in native `Map`
+  * `Ember.Map` adds a static `create` method (which simply instantiates itself with `new Ember.Map()`)
+  * `Ember.Map` does not accept constructor arguments
+  * `Ember.Map` does not have:
+    * `@@species`
+    * `@@iterator`
+    * `entries`
+    * `values`
+
+  This implementation adds a deprecated backwards compatibility for:
+
+  * `copy`
+  * `isEmpty`
+
+  ## Why is this written this way?!?
+
+  This is needed because `Map` requires instantiation with `new` and by default
+  Babel transpilation will do `superConstructor.apply(this, arguments)` which
+  throws an error with native `Map`.
+
+  The desired code (if we lived in an "only native class" world) would be:
+
+  ```js
+  export default class MapWithDeprecations extends Map {
+    constructor(options) {
+      super();
+      this.defaultValue = options.defaultValue;
+    }
+
+    get(key) {
+      let hasValue = this.has(key);
+
+      if (hasValue) {
+        return super.get(key);
+      } else {
+        let defaultValue = this.defaultValue(key);
+        this.set(key, defaultValue);
+        return defaultValue;
+      }
+    }
+  }
+  ```
+*/
+export default class MapWithDeprecations {
+  constructor(options) {
+    this._map = new Map();
+  }
+
+  copy() {
+    deprecate(
+      'Calling `.copy()` on a map generated by ember-data is deprecated, please migrate to using native Map functionality only.',
+       false,
+      { id: 'ember-data.map.copy', until: '3.5.0' }
+    );
+
+    // can't just pass `this._map` here because IE11 doesn't accept
+    // constructor args with its `Map`
+    let newMap = new MapWithDeprecations();
+    this._map.forEach(function(value, key) {
+      newMap.set(key, value)
+    });
+
+    return newMap;
+  }
+
+  isEmpty() {
+    deprecate(
+      'Calling `.isEmpty()` on a map generated by ember-data is deprecated, please migrate to using native Map functionality only.',
+       false,
+      { id: 'ember-data.map.isEmpty', until: '3.5.0' }
+    );
+
+    return this.size === 0;
+  }
+
+  // proxy all normal Map methods to the underlying Map
+  get size() { return this._map.size; }
+  clear() { return this._map.clear(...arguments) }
+  delete() { return this._map.delete(...arguments) }
+  entries() { return this._map.entries(...arguments) }
+  forEach() { return this._map.forEach(...arguments) }
+  get() { return this._map.get(...arguments) }
+  has() { return this._map.has(...arguments) }
+  keys() { return this._map.keys(...arguments) }
+  set() { return this._map.set(...arguments) }
+  values() { return this._map.values(...arguments) }
+}

addon/-private/system/model/errors.js

@@ -4,7 +4,7 @@ import ArrayProxy from '@ember/array/proxy';
 import { set, get, computed } from '@ember/object';
 import { isEmpty } from '@ember/utils';
 import { makeArray, A } from '@ember/array';
-import MapWithDefault from '@ember/map/with-default';
+import MapWithDefault from '../map-with-default';
 import { deprecate, warn } from '@ember/debug';
 
 /**
@@ -121,11 +121,11 @@ export default ArrayProxy.extend(Evented, {
 
   /**
     @property errorsByAttributeName
-    @type {Ember.MapWithDefault}
+    @type {MapWithDefault}
     @private
   */
   errorsByAttributeName: computed(function() {
-    return MapWithDefault.create({
+    return new MapWithDefault({
       defaultValue() {
         return A();
       }

addon/-private/system/model/model.js

@@ -7,7 +7,7 @@ import EmberObject, {
   get,
   observer
 } from '@ember/object';
-import Map from '@ember/map';
+import Map from '../map';
 import { DEBUG } from '@glimmer/env';
 import { assert, warn } from '@ember/debug';
 import { PromiseObject } from "../promise-proxies";
@@ -1399,7 +1399,7 @@ Model.reopenClass({
 
    @property relationships
    @static
-   @type Ember.Map
+   @type Map
    @readOnly
    */
 
@@ -1522,7 +1522,7 @@ Model.reopenClass({
 
    @property relationshipsByName
    @static
-   @type Ember.Map
+   @type Map
    @readOnly
    */
   relationshipsByName: relationshipsByNameDescriptor,
@@ -1565,11 +1565,11 @@ Model.reopenClass({
 
    @property fields
    @static
-   @type Ember.Map
+   @type Map
    @readOnly
    */
   fields: computed(function() {
-    let map = Map.create();
+    let map = new Map();
 
     this.eachComputedProperty((name, meta) => {
       if (meta.isRelationship) {
@@ -1674,11 +1674,11 @@ Model.reopenClass({
 
    @property attributes
    @static
-   @type {Ember.Map}
+   @type {Map}
    @readOnly
    */
   attributes: computed(function() {
-    let map = Map.create();
+    let map = new Map();
 
     this.eachComputedProperty((name, meta) => {
       if (meta.isAttribute) {
@@ -1727,11 +1727,11 @@ Model.reopenClass({
 
    @property transformedAttributes
    @static
-   @type {Ember.Map}
+   @type {Map}
    @readOnly
    */
   transformedAttributes: computed(function() {
-    let map = Map.create();
+    let map = new Map();
 
     this.eachAttribute((key, meta) => {
       if (meta.type) {

addon/-private/system/relationships/ext.js

@@ -1,7 +1,7 @@
 import { A } from '@ember/array';
 import { computed } from '@ember/object';
-import MapWithDefault from '@ember/map/with-default';
-import Map from '@ember/map';
+import MapWithDefault from '../map-with-default';
+import Map from '../map';
 import { assert } from '@ember/debug';
 import {
   typeForRelationshipMeta,
@@ -56,7 +56,7 @@ export const relatedTypesDescriptor = computed(function() {
 }).readOnly();
 
 export const relationshipsByNameDescriptor = computed(function() {
-  let map = Map.create();
+  let map = new Map();
 
   this.eachComputedProperty((name, meta) => {
     if (meta.isRelationship) {

addon/-private/system/store.js

@@ -6,7 +6,7 @@ import { A } from '@ember/array';
 
 import { copy } from '@ember/object/internals';
 import EmberError from '@ember/error';
-import MapWithDefault from '@ember/map/with-default';
+import MapWithDefault from './map-with-default';
 import { run as emberRun } from '@ember/runloop';
 import { set, get, computed } from '@ember/object';
 import RSVP from 'rsvp';
@@ -230,7 +230,7 @@ Store = Service.extend({
     this._updatedInternalModels = [];
 
     // used to keep track of all the find requests that need to be coalesced
-    this._pendingFetch = MapWithDefault.create({ defaultValue() { return []; } });
+    this._pendingFetch = new MapWithDefault({ defaultValue() { return []; } });
 
     this._adapterCache = Object.create(null);
     this._serializerCache = Object.create(null);

addon/adapters/rest.js

@@ -6,7 +6,6 @@
 import $ from 'jquery';
 
 import { Promise as EmberPromise } from 'rsvp';
-import MapWithDefault from '@ember/map/with-default';
 import { get } from '@ember/object';
 import { run } from '@ember/runloop';
 import Adapter from "../adapter";
@@ -22,7 +21,8 @@ import {
   ConflictError,
   ServerError,
   TimeoutError,
-  AbortError
+  AbortError,
+  MapWithDefault
 } from '../-private';
 import { instrument } from 'ember-data/-debug';
 import { warn, deprecate } from '@ember/debug';
@@ -901,7 +901,7 @@ const RESTAdapter = Adapter.extend(BuildURLMixin, {
                       loaded separately by `findMany`.
   */
   groupRecordsForFindMany(store, snapshots) {
-    let groups = MapWithDefault.create({ defaultValue() { return []; } });
+    let groups = new MapWithDefault({ defaultValue() { return []; } });
     let adapter = this;
     let maxURLLength = this.maxURLLength;