ember-concurrency 2.0 is primarily an "engine" replacement. Internally, its been substantially rewritten and decoupled from Ember at it's core. This will enable a much more maintainable codebase, as well as setting the stage for potential extraction of core primatives for us in the broader JavaScript ecosystem.

The application developer-facing changes are fairly minimal, and there are few potentially breaking semantic changes to the operation of the addon.

Please review the 2.0 Upgrade Guide for a thorough description of the changes for app and addon users alike.

New Features

• Use @tracked underneath on Ember 3.16+ (#354)

  Note: Within applications with both tracked & computed properties, if using a native getter to access task state, and wishing to use it alongside a computed property, @dependantKeyCompat will need to be used on the getter as expected with any other tracked-prop using getter.

• Implement decorators from ember-concurrency-decorators. The "nice" decorators from ember-concurrency-decorators are now built-in to ember-concurrency, without requiring an additional addon or seperate import. All decorators are available for import directly from the top-level ember-concurrency package.

  Addon maintainers: Please see notes in UPGRADING-2.x.md if you're using decorators currently, and wish to support both ember-concurrency 1.x and 2.x at runtime.

Enhancements

• Migrate task lifetimes to @ember/destroyable underneath, rather than patching willDestroy (#377).

  Potentially breaking: this drops support for Node 8 and Ember < 3.8 LTS

• [docs] Rewrite documentation to use native classes and decorators, and update tutorial to show rewriting of async function code, rather than Promise code, as is more common today.

• Make Task#cancelAll and TaskInstance#cancel awaitable (#396). See topic in UPGRADING-2.x.md for more info.

Removals

• Remove ability to directly use tasks with {{action}} helper stuff (deprecated in 1.3.0) (#374)

• Remove get and set compatibility methods from Task, TaskGroup, and TaskInstance.

• Drop unused broccoli-file-creator and ember-maybe-import-regenerator dependencies.

  Note on ember-maybe-import-regenerator: This was originally added back when generator support in browsers was far lower and Babel 5 and 6 were used. The addon does nothing for Babel 7, which is used for ember-concurrency these days. Tweaking config/targets.js or adding the regenerator Babel plugin to your babel config can be done instead if the regenerator runtime is needed to transpile generators for older browsers.