Feb 29, 2016 – By Matthew Beale

Ember.js 2.4, a minor version release of Ember with backwards compatible changes, is released today. After an additional six-week maturation cycle as a stable release version, 2.4 will be declared Ember's first Long-Term Support (LTS) release. For more about the LTS process and what you should expect, see last week's post Announcing Ember's First LTS Release.

Ember.js 2.5 beta, the branch of Ember that will be released as stable in roughly six weeks, is also being released today.

Changes in Ember.js 2.4

No new features are added in Ember core in 2.4. Instead this release is primarily comprised of bugfixes making it an excellent LTS candidate. In general the core team and community have remained active around other highly visible parts of the Ember stack (Ember CLI, Ember Data, FastBoot, Glimmer, etc).

In six weeks, the current release build of 2.4 will become Ember's first LTS release. Builds on the LTS channel will receive critical bugfixes covering the subsequent six release cycles (~36 weeks), and security patches for the subsequent ten release cycles (~60 weeks). If your organization intends to remain on the LTS channel, we strongly suggest you attempt updating your application to 2.4 and open any issues in the next six weeks.

For more details on changes landing in 2.4, review the Ember.js 2.4.1 CHANGELOG.

Ember.js 2.5 beta

Ember 2.5 introduces several minor public API additions.

Ember.assign

Ember.assign is a polyfill for the ES2015 Object.assign feature. assign copies the values of all enumerable own properties from one or more source objects to a target object. For example:

let a = {first: 'John'};
let b = {last: 'Lennon'};
let c = {band: 'The Beatles'};

Ember.assign(a, b, c);

// a === {first: 'John', last: 'Lennon', band: 'The Beatles'}
// b === {last: 'Lennon'}
// c === {band: 'The Beatles'}

For more specifics on assign, see the MDN documentation.

Local Lookup Compatibility

As part of the "pods" directory layout, we intend to introduce a feature called "local lookup". This feature will allow for the creation of components available only in a single template, instead of being globally scoped as they must be today. lookup and resolve in Ember 2.5 will accept an optional source property on their options argument. This API change will local lookup to be implemented outside of Ember via the ember-cli/ember-resolver library.

Native Event Test Helpers

Ember's acceptance test helpers, such as click() have previously used jQuery event triggers. In 2.5 this behavior has been altered to trigger native events via dispatchEvent. This change is expected to be completely backwards compatible, and enable the triggering of non-jQuery event listeners in acceptance tests.

For more details on changes landing in 2.5, review the Ember.js 2.5.0-beta.1 CHANGELOG.

Update: Ember 2.4.1 Released

Shortly after Ember 2.4.0 was released, we have identified a regression that caused incorrect deprecation warnings to be emitted. Specifically, we intended to emit deprecation warnings when either (or both) of the legacy addons are installed. Instead, the check was inverted, causing the deprecation warnings to be emitted only if the addons are not installed.

Ember 2.4.1 has been released to address this error.

It should be noted that the production builds for 2.4.0 are not affected by this regression, since deprecation warnings are only present in development builds.