Decouple test from the default resolver for initializers_test

[karthiicksiva]

#15058

[karthiicksiva]

I understand that, we are pausing & resuming the test runner here. But why? Would like to know the reason behind this.

@mixonic

[mixonic]

app.boot().then(() => { is not inside a runloop, so the thennable callback will be called in an autorun making it async. I think you could avoid the async-ness if you wrapped the promise a runloop, it would then flush in the actions queue. Nice catch:

try {
  this.runTask(() => {
    app.boot().then(app => {
      assert.ok(false, 'The boot promise should not resolve when there is a boot error');
    }, error => {
      assert.ok(error instanceof Error, 'The boot promise should reject with an error');
      assert.equal(error.message, 'boot failure');
    });
  });
} catch (error) {
  // ...

[mixonic]

Many of the changed I'd like to see are already laid out in #15362, but I'll reiterate a few:

• assert is passed as the first argument to tests, should be used for assertions instead of the globals.
• this.runTask is preferred over run
• run shouldn't be needed around initializer calls

Excellent beginning though, thank you for the continued iteration!!

[mixonic]

Using applicationOptions is preferred here. Replace createApplication through teardown with:

 get applicationOptions() {
    return assign(super.applicationOptions, {
      rootElement: '#one'
    });
  }

  createSecondApplication(options, MyApplication=Application) {
    let myOptions = assign(this.applicationOptions, {
      rootElement: '#two'
    }, options);
    let secondApp = this.secondApp = MyApplication.create(myOptions);
    return secondApp;
  }

  teardown() {
    super.teardown();

    if (this.secondApp) {
      this.runTask(() => this.secondApp.destroy());
    }
  }

More details at https://github.com/emberjs/ember.js/pull/15362/files#r122541946

[karthiicksiva]

This PR is ready to go. // @mixonic

[mixonic]

This looks great to me, thanks @Karthiick 👍 I kicked the sauce build, it had what I presume was a spurious failure.