Ember-Component: Failing test when throwing Errors in init() despite using workaround

[jnfingerle]

Hi,

I'm upgrading a large app to Octane. A number of our Ember.Components throw exceptions in init(). Our test have the workaround for render() not throwing: We have our own Ember.onerror for the test. This worked before. With current Ember this works at first, but in cases where the Component is the only thing in the template, this leads to another Error "TypeError: Cannot read property 'firstNode' of null".

For whatever reason I couldn't recreate this as a twiddle, but here's my code:

https://github.com/jnfingerle/ember-issue-component-test

test-component.js:

import Component from '@ember/component';

export default class TestComponent extends Component {
    init(){
        throw new Error('Error');
    }
} 

test-component-test.js:

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

module('Integration | Component | test-component', function(hooks) {
  setupRenderingTest(hooks);

  test('rejects doesn\'t catch exception', async function(assert) {
      assert.expect(1);
    assert.rejects(render(hbs`<TestComponent />`));
  });

  test('Workaround: errorHandler works at first, but gets called twice (2nd:  TypeError: Cannot read property \'firstNode\' of null)', async function(assert) {
      assert.expect(1);
    const originalErrorHandler = Ember.onerror;
    try {
        Ember.onerror = function(error){
            assert.ok(true, 'On Error:' + error);
        }
        await render(hbs`<TestComponent />`);
    } finally {
        Error.onerror = originalErrorHandler;
    }
  });

  test('with additional <div>s all works as expected', async function(assert) {
      assert.expect(1);
    const originalErrorHandler = Ember.onerror;
    try {
        Ember.onerror = function(error){
            assert.ok(true, 'On Error:' + error);
        }
        await render(hbs`<div><TestComponent /></div>`);
    } finally {
        Error.onerror = originalErrorHandler;
    }
  });
});

package.json

{
  "name": "component-test",
  "version": "0.0.0",
  "private": true,
  "description": "Small description for component-test goes here",
  "repository": "",
  "license": "MIT",
  "author": "",
  "directories": {
    "doc": "doc",
    "test": "tests"
  },
  "scripts": {
    "build": "ember build --environment=production",
    "lint": "npm-run-all --aggregate-output --continue-on-error --parallel lint:*",
    "lint:hbs": "ember-template-lint .",
    "lint:js": "eslint .",
    "start": "ember serve",
    "test": "npm-run-all lint:* test:*",
    "test:ember": "ember test"
  },
  "devDependencies": {
    "@ember/optional-features": "^1.3.0",
    "@glimmer/component": "^1.0.0",
    "@glimmer/tracking": "^1.0.0",
    "babel-eslint": "^10.1.0",
    "broccoli-asset-rev": "^3.0.0",
    "ember-auto-import": "^1.5.3",
    "ember-cli": "~3.17.0",
    "ember-cli-app-version": "^3.2.0",
    "ember-cli-babel": "^7.18.0",
    "ember-cli-dependency-checker": "^3.2.0",
    "ember-cli-htmlbars": "^4.2.3",
    "ember-cli-inject-live-reload": "^2.0.2",
    "ember-cli-sri": "^2.1.1",
    "ember-cli-uglify": "^3.0.0",
    "ember-data": "~3.17.0",
    "ember-export-application-global": "^2.0.1",
    "ember-fetch": "^7.0.1",
    "ember-load-initializers": "^2.1.1",
    "ember-maybe-import-regenerator": "^0.1.6",
    "ember-qunit": "^4.6.0",
    "ember-resolver": "^7.0.0",
    "ember-source": "~3.17.0",
    "ember-template-lint": "^2.4.0",
    "ember-welcome-page": "^4.0.0",
    "eslint": "^6.8.0",
    "eslint-plugin-ember": "^7.10.1",
    "eslint-plugin-node": "^11.0.0",
    "loader.js": "^4.7.0",
    "npm-run-all": "^4.1.5",
    "qunit-dom": "^1.1.0"
  },
  "engines": {
    "node": "10.* || >= 12"
  },
  "ember": {
    "edition": "octane"
  }
}

[pzuraq]

This will be fixed by #18878