If '' is an Angular component, then verify that it is part of this module

Question

I am new in Angular2. I have tried to create a component but showing an error.

This is the app.component.ts file.

import { Component } f         


        

Answer 1

In my case I was writing unit tests for a component that uses sub-components, and I was writing tests to make sure those subcomponents were in the template:

it('should include the interview selection subview', () => {
    expect(fixture.debugElement.query(By.css('app-interview')))
    .toBeTruthy()  
  }); 

I didn't get an error, but a warning:

WARN: ''app-interview' is not a known element:

1. If 'app-interview' is an Angular component, then verify that it is part of this module. WARN: ''app-interview' is not a known element:
2. If 'app-interview' is an Angular component, then verify that it is part of this module.
3. If 'app-interview' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.'

Also, the subcomponent did not show inside the browser during testing.

I used ng g c newcomponent to generate all the components, so they were already declared in the appmodule, but not the test module that for the component I was spec'ing.

beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ EditorComponent,
        InterviewComponent]
    })
    .compileComponents();
  }));