Test error "Cannot read property 'hasRegistration' of undefined"

[kaermorchen]

How to detect:

ember new test-app
cd test-app\
ember s

We have green tests

ember g helper foo-bar

We have an error - "Uncaught TypeError: Cannot read property 'hasRegistration' of undefined"

// test-app/tests/integration/helpers/foo-bar-test.js

import { module, test } from 'qunit';
import { setupRenderingTest } from 'ember-qunit';
import { render } from '@ember/test-helpers';
import hbs from 'htmlbars-inline-precompile';

module('Integration | Helper | foo-bar', function(hooks) {
  setupRenderingTest(hooks);

  // Replace this with your real tests.
  test('it renders', async function(assert) {
    this.set('inputValue', '1234');

    await render(hbs`{{foo-bar inputValue}}`);

    assert.equal(this.element.textContent.trim(), '1234');
  });
});

Output from ember version --verbose && npm --version:

ember-cli: 3.1.2
http_parser: 2.7.0
node: 8.9.1
v8: 6.1.534.47
uv: 1.15.0
zlib: 1.2.11
ares: 1.10.1-DEV
modules: 57
nghttp2: 1.25.0
openssl: 1.0.2m
icu: 59.1
unicode: 9.0
cldr: 31.0.1
tz: 2017b
os: win32 x64
5.6.0

[yarigpopov]

I have the same issue

[yarigpopov]

In my case it was something with devTools and Ember Inspector. After reopenning devtools everything went back to normal

[sivakumar-kailasam]

Reported in emberjs/ember-inspector#818

[Turbo87]

closing in favor of emberjs/ember-inspector#818