Destructuring of Ember.testing will not work.

[rwjblue]

Ember.testing is a getter/setter in Ember, and destructuring like this will only read its value at the time the module is evaluated. In this case, Ember.testing will most likely be false when the module is evaluated, then change to true during the test. This behavior somewhat recently changed in emberjs/ember-test-helpers#227 (which is included in ember-cli-qunit@4.1.0 / ember-qunit@3.0.0).

I believe the fix here would be to remove the destructuring, and use Ember.testing directly inline.

ember-l10n/addon/services/l10n.js

Lines 4 to 17 in 256eb16

	const {
	computed,
	Service,
	inject,
	RSVP: { Promise },
	get,
	merge,
	copy,
	typeOf: getTypeOf,
	Evented,
	isNone,
	Logger,
	testing
	} = Ember;

ember-l10n/addon/services/l10n.js

Lines 536 to 538 in 256eb16

	if (testing) {
	return;
	}

[arm1n]

Thanks a lot for this hint, we're currently working on version 1.0.0 using latest Ember with new modules API and hope to have import { isTesting, setTesting } from '@ember/test' available as soon as possible (ember-cli/ember-rfc176-data#12), then this issue should be gone anyways.

[mydea]

This is not used anymore, so I'm closing this!