Angular 2 Testing: Get Value from ngModel

问题

I'm trying to write a test that asserts on Angular's ngModel attribute. At this point, I can easily test the label. However, I am not able to select the value from ngModel

Question What is the best way to get the value from ngModel?

HTML:

<div name="customerName">
    <label>Customer Name: </label>
    <div>
        <input type="text" class="form-control" [ngModel]="customer.name" asInline disabled />
    </div>
</div>

Test

it('bindings', () => {
    fixture = TestBed.createComponent(CustomerComponent);
    fixture.detectChanges();

    // this works
    expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] label').textContent).toEqual('Customer Name: '); 
    // this assert fails
    expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] div input').value).toEqual('Bobby Tables'); 
});

回答1:

Use async together with whenStable

it('should recognize a timepicker', async(() => {
  fixture = TestBed.createComponent(ExampleComponent);
  fixture.detectChanges();

  fixture.whenStable().then(() => {
    expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] label').textContent).toEqual('Customer Name: ');

    expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] div input').value).toEqual('Bobby Tables');
  });   
}));

Plunker Example

or fakeAsync with tick:

it('should recognize a timepicker', fakeAsync(() => {
  fixture = TestBed.createComponent(ExampleComponent);
  fixture.detectChanges();
  tick();

  expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] label').textContent).toEqual('Customer Name: ');

  expect(fixture.debugElement.nativeElement.querySelector('[name=customerName] div input').value).toEqual('Bobby Tables');
}));

Plunker Example

And don't forget to import FormsModule:

TestBed.configureTestingModule({
    imports: [FormsModule],
    ...

来源：https://stackoverflow.com/questions/42983135/angular-2-testing-get-value-from-ngmodel