Error: Please call "TestBed.compileComponents" before your test

Question

I'm getting this error:

Error: This test module uses the component MessagesComponent which is using a "templateUrl", but they were never compiled. Please call "TestBed.compileComponents" before your test.

When trying to run this simple test Angular 2 & Jasmine Test:

  let comp:    MessagesComponent;
let fixture: ComponentFixture<MessagesComponent>;

describe('MessagesComponent', () => {
    beforeEach(() => {


        TestBed.configureTestingModule({
            declarations: [ MessagesComponent ],
            providers:    [ {provide: DataService, useValue: {} } ]

        })
            .compileComponents(); // compile template and css

        fixture = TestBed.createComponent(MessagesComponent);
        comp = fixture.componentInstance;

    });

    it('example', () => {
        expect("true").toEqual("true");
    });
});

I think it might be due to something with my webpack test configuration:

'use strict';

const path = require('path');
const webpack = require('webpack');

module.exports = {
    devtool: 'inline-source-map',
    module: {
        loaders: [
            { loader: 'raw', test: /\.(css|html)$/ },
            { exclude: /node_modules/, loader: 'ts', test: /\.ts$/ }
        ]
    },
    resolve: {
        extensions: ['', '.js', '.ts'],
        modulesDirectories: ['node_modules'],
        root: path.resolve('.', 'src')
    },
    tslint: {
        emitErrors: true
    }
};

pe8ter · Accepted Answer · 2016-11-05T03:54:39.167

33

Template fetching is asynchronous when your templates are not inlined into your components, so you need to tell Jasmine that. Change

beforeEach(() => {
    TestBed.configureTestingModule({ ... })
        .compileComponents();
    fixture = TestBed.createComponent(MessagesComponent);
    comp = fixture.componentInstance;
});

to

beforeEach(async(() => {
    TestBed.configureTestingModule({ ... })
        .compileComponents()
        .then(() => {
            fixture = TestBed.createComponent(MessagesComponent);
            comp = fixture.componentInstance;
        });
}));

edited Nov 05 '16 at 03:54

answered Nov 04 '16 at 22:52

pe8ter

1,263
12
10

should I change the it(...) method in any way? – CommonSenseCode Nov 04 '16 at 22:59
Only if the `it()` does anything asynchronously, for example, if it fetches data from a service. It's totally okay if the the `beforeEach()` needs to be asynchronous but the `it()` does not. – pe8ter Nov 04 '16 at 23:09
weird I asked because I keep gettin the same error message as posted in my original question but at least now it says 1 of 1 failed – CommonSenseCode Nov 04 '16 at 23:17
1

Oh, I missed something: `...compileComponents().then(() => { ... })` and create your component inside that function. You're creating the component before the template is loaded and compiled. – pe8ter Nov 04 '16 at 23:55
3

please post the code complete how it should be I really don't understand – CommonSenseCode Nov 04 '16 at 23:57
On mobile. Will modify my answer tonight. – pe8ter Nov 05 '16 at 00:03
1

please don't forget about this :) – CommonSenseCode Nov 05 '16 at 14:36

score 5 · Answer 2 · answered Sep 18 '17 at 20:07

Since you are already using webpack, theoretically you should not have to call the compileComponents() function according to the official doc here, because webpack inlines templates and css as part of the automated build process that precedes running the test.

One possible reason that your template/css are not inlined is the IDE(VisualStudio/WebStorm/IntelliJ) auto compiles your ts to js and the webpack loaders which target for js/ts files are trying to get applied on the already compiled js files instead of the source ts files.

Error: Please call "TestBed.compileComponents" before your test

2 Answers2

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