[CLEANUP] Remove deprecated assign polyfill

- Remove the polyfill itself.
- Remove the entire `@ember/polyfills` package, which is now empty.
- Remove the `Ember.platform` API, which has loooong been unused.

ember-cli-build.js

@@ -221,7 +221,6 @@ function templateCompilerBundle(emberPackages, transpileTree) {
           '@ember/debug/**',
           '@ember/deprecated-features/**',
           '@ember/error/**',
-          '@ember/polyfills/**',
           'ember/version.js',
           'ember-babel.js',
           'ember-template-compiler/**',

packages/ember/index.ts

@@ -92,7 +92,6 @@ import Observable from '@ember/object/observable';
 import { addObserver, removeObserver } from '@ember/object/observers';
 import ObjectProxy from '@ember/object/proxy';
 import PromiseProxyMixin from '@ember/object/promise-proxy-mixin';
-import { assign } from '@ember/polyfills';
 import AutoLocation from '@ember/routing/auto-location';
 import HashLocation from '@ember/routing/hash-location';
 import HistoryLocation from '@ember/routing/history-location';
@@ -359,9 +358,6 @@ const PartialEmber = {
   // ****@ember/object/proxy****
   ObjectProxy,
 
-  // ****@ember/polyfills****
-  assign,
-
   // ****@ember/routing/-internals****
   RouterDSL,
   controllerFor,
@@ -463,12 +459,6 @@ const PartialEmber = {
   // ****@ember/controller, @ember/service****
   inject,
 
-  // Non-imported
-  platform: {
-    defineProperty: true,
-    hasPropertyAccessors: true,
-  },
-
   __loader: {
     require,
     define,

packages/ember/tests/reexports_test.js

@@ -260,10 +260,6 @@ let allExports = [
   // @ember/object/proxy
   ['ObjectProxy', '@ember/object/proxy', 'default'],
 
-  // @ember/polyfills
-  ['assign', '@ember/polyfills', 'assign'],
-  ['platform.hasPropertyAccessors', '@ember/polyfills', 'hasPropertyAccessors'],
-
   // @ember/routing/auto-location
   ['AutoLocation', '@ember/routing/auto-location', 'default'],
 

tests/docs/expected.js

@@ -99,13 +99,11 @@ module.exports = {
     'cache',
     'cached',
     'cacheFor',
-    'camelize',
     'canCatalogEntriesByType',
     'cancel',
     'cancelRouterSetup',
     'canInvoke',
     'capabilities',
-    'capitalize',
     'captureRenderTree',
     'catalogEntriesByType',
     'catch',
@@ -151,7 +149,6 @@ module.exports = {
     'debugCreationStack',
     'debugger',
     'debugPreviousTransition',
-    'decamelize',
     'decrementProperty',
     'defer',
     'deferReadiness',
@@ -519,7 +516,6 @@ module.exports = {
     'typeOf',
     'typeWatchers',
     'unbound',
-    'underscore',
     'union',
     'uniq',
     'uniqBy',
@@ -537,7 +533,6 @@ module.exports = {
     'userAgent',
     'validationCache',
     'visit',
-    'w',
     'wait',
     'waitForDOMReady',
     'warn',

type-tests/ember/ember-module-tests.ts

@@ -21,11 +21,6 @@ Ember.addObserver({ a: 'foo' }, 'a', {}, () => {});
 // assert
 Ember.assert('2+2 should always be 4', 2 + 2 === 4);
 // assign
-const o1 = Ember.assign({ a: 1 }, { b: 2 });
-expectTypeOf(o1.a).toBeNumber();
-expectTypeOf(o1.b).toBeNumber();
-// @ts-expect-error
-o1.c;
 // Ember.bind // @ts-expect-error
 // cacheFor
 expectTypeOf(Ember.cacheFor({ a: 123 }, 'a')).toEqualTypeOf<number | undefined>();

type-tests/ember/utils.ts

@@ -44,14 +44,6 @@ function testIsNone() {
   Ember.isNone('', '');
 }
 
-function testAssign() {
-  expectTypeOf(Ember.assign({ first: 'Tom' }, { middle: 'M' }, { last: 'Dale' })).toEqualTypeOf<{
-    first: string;
-    middle: string;
-    last: string;
-  }>();
-}
-
 function testOnError() {
   Ember.onerror = (error) => {
     fetch('/report-error', {
@@ -120,21 +112,3 @@ declare const fileList: FileList;
   expectTypeOf(Ember.typeOf(new Date() as RegExp | Date)).toEqualTypeOf<'regexp' | 'date'>();
   expectTypeOf(Ember.typeOf({ randomObject: true })).toEqualTypeOf<'object'>();
 })();
-
-(() => {
-  /* assign */
-  Ember.assign({}, { a: 'b' });
-  expectTypeOf(Ember.assign({}, { a: 'b' }).a).toBeString();
-  expectTypeOf(Ember.assign({ a: 6 }, { a: 'b' }).a).toBeString();
-  expectTypeOf(Ember.assign({ a: 6 }, {}).a).toBeNumber();
-  // @ts-expect-error
-  Ember.assign({ b: 6 }, {}).a;
-  expectTypeOf(Ember.assign({}, { b: 6 }, {}).b).toBeNumber();
-  expectTypeOf(Ember.assign({ a: 'hello' }, { b: 6 }, {}).a).toBeString();
-  expectTypeOf(Ember.assign({ a: 'hello' }, { b: 6 }, { a: true }).a).toBeBoolean();
-  // @ts-expect-error
-  Ember.assign({ a: 'hello' }, '', { a: true }).a;
-  expectTypeOf(
-    Ember.assign({ d: ['gobias industries'] }, { a: 'hello' }, { b: 6 }, { a: true }).d
-  ).toEqualTypeOf<string[]>();
-})();

types/preview/ember/index.d.ts

@@ -8,7 +8,6 @@ declare module 'ember' {
   import type * as EmberTemplateNs from '@ember/template';
   import * as EmberTemplateHandlebarsNs from '@ember/template/-private/handlebars';
   import type * as EmberServiceNs from '@ember/service';
-  import type * as EmberPolyfillsNs from '@ember/polyfills';
   import type * as EmberUtilsNs from '@ember/utils';
   import type * as EmberRunloopNs from '@ember/runloop';
   import * as EmberObjectNs from '@ember/object';
@@ -293,11 +292,6 @@ declare module 'ember' {
     interface Run extends RunFn, EmberRunloop {}
     const run: Run;
 
-    const platform: {
-      defineProperty: boolean;
-      hasPropertyAccessors: boolean;
-    };
-
     /**
      * `getEngineParent` retrieves an engine instance's parent instance.
      */
@@ -339,12 +333,6 @@ declare module 'ember' {
      */
     const isEqual: typeof EmberUtilsNs.isEqual;
     const typeOf: typeof EmberUtilsNs.typeOf;
-    /**
-     * Copy properties from a source object to a target object.
-     * @deprecated until v5.0. You should replace any calls to `Ember.assign`
-     *   with `Object.assign` or use the object spread operator.
-     */
-    const assign: typeof EmberPolyfillsNs.assign;
     const guidFor: typeof EmberObjectInternalsNs.guidFor;
 
     /**

types/preview/index.d.ts

@@ -89,9 +89,6 @@ import './@ember/object/observers';
 import './@ember/object/promise-proxy-mixin';
 import './@ember/object/proxy';
 
-import './@ember/polyfills';
-import './@ember/polyfills/types';
-
 import './@ember/routing';
 import './@ember/routing/-private/router-dsl';
 import './@ember/routing/auto-location';

types/publish.mjs

@@ -254,8 +254,6 @@ const PREVIEW_MODULES = [
   '@ember/object/observers.d.ts',
   '@ember/object/promise-proxy-mixin.d.ts',
   '@ember/object/proxy.d.ts',
-  '@ember/polyfills/index.d.ts',
-  '@ember/polyfills/lib/assign.d.ts',
   '@ember/renderer/index.d.ts',
   '@ember/routing/-internals.d.ts',
   '@ember/routing/auto-location.d.ts',