You attempted to access the isNamespace property (of service:features)

[Leooo]

Seeing this error in tests on Ember >= 3.4 when using withFeature helper:

You attempted to access the isNamespace property (of service:features)

Fixed it by extending the features service in the app with:

///app/services/features.js
import FeaturesService from 'ember-feature-flags/services/features';
import config from '../config/environment';

export default FeaturesService.extend({
  config,
  init() { //see https://github.com/kategengler/ember-feature-flags/blob/06b33fd5d6e78538c8611cdf134e93adc3a04e71/app/services/features.js
    this._super(...arguments);
    if (config.featureFlags) {
      this.setup(config.featureFlags);
    }
  },
  unknownProperty(key) {
    if (key === 'isNamespace') {
      return null; //see https://github.com/emberjs/ember.js/issues/16521#issuecomment-382465594 (need `null` or `undefined`)
    }
    return this._super(...arguments);
  }

[kategengler]

Hi! Are you still using "old" style acceptance tests? These would have moduleForAcceptance etc?

If not, you should use the enableFeature test helper https://github.com/kategengler/ember-feature-flags#enablefeature

[Leooo]

yes indeed, it's on Ember 3.4 with old-style acceptance tests - want to keep the upgrade of Ember and of test module suites separate on this one.

That was also my guess that it would disappear with new test syntax, still worth mentioning it in here in case someone else bumps into that. Noted that https://github.com/kategengler/ember-feature-flags#enablefeature will be the way to go in the future thanks.

Happy to close if nothing to be done on this one, let me know.