Deprecations Added in Ember 4.x

What follows is a list of deprecations introduced to Ember during the 4.x cycle.

For more information on deprecations in Ember, see the main deprecations page.

Deprecations Added in 4.0.0

§ Ember.assign

until: 5.0.0
id: ember-polyfills.deprecate-assign

Use of Ember.assign is deprecated. You should replace any calls to Ember.assign with Object.assign or use the object spread operator.


import { assign } from '@ember/polyfills';

var a = { first: 'Yehuda' };
var b = { last: 'Katz' };
assign(a, b); // a == { first: 'Yehuda', last: 'Katz' }, b == { last: 'Katz' }


var a = { first: 'Yehuda' };
var b = { last: 'Katz' };
Object.assign(a, b); // a == { first: 'Yehuda', last: 'Katz' }, b == { last: 'Katz' }

Deprecations Added in 4.1.0

§ AutoLocation Class

until: 5.0.0
id: deprecate-auto-location


Several years ago only some browsers supported the (then) new History Location API. Others could only serialize the router location into an url hash my/path#/ember/route.

To handle this dynamically, Ember built an AutoLocation that would feature-detect and use either 'hash' or 'history' as the underlying mechanism.

These days, virtually all browsers support the history API, so this is what 'auto' will resolve to in almost every case. Since 'auto' has served its purpose, it's being removed.

Required Changes

Set locationType in config/environment.js to 'history'. This is it, your app should work just like it used to.

Unless you know for sure that you need to keep feature detection in place (few need that), or that you'd like to use the 'hash' location strategy (rarely used in browsers, but can be useful for mobile apps delivered via a webview).

Advanced Stuff

If you implemented your own Location class and used the detect method, this one is now deprecated. If you need feature detection you can run your detection code in app.js, before setting the location type.

// app/router.js
export default class Router extends EmberRouter {
  location = (historyFeatureDetection() ? 'history' : 'hash');
  // …

For more background, read the RFC.