如何在Angular2中实际触发点击事件并检查结果

Question

I want to actually check, that the selected attribute has been rendered with a true instead of an undefined.

My working (manually tested) Component functionality:

export class PlayerSelectorComponent implements OnInit {

    players: any = []

    ...

    toggleSelectPlayer( player: any ) {
        if (player.selected) {
            player.selected = false
        }
        else {
            player.selected = true
        }
    }

}

Here is the template:

 <ul class="list-group">
     <player-row *ngFor="let player of players"
                 [player]="player"
                 [selected]="player.selected"
                 (click) = "toggleSelectPlayer(player)">
     </player-row>
 </ul>

Here is the test code:

it( 'should render a player as selected after a user clicks on the player row', fakeAsync( () => {
    let player = fixture.debugElement.query( By.css( '.player-row' ) )
    expect( player.attributes.selected ).toBe( undefined )
    player.triggerEventHandler( 'click', null )
    tick()
    fixture.detectChanges()
    player = fixture.debugElement.query( By.css( '.player-row' ) )
    expect( player.attributes.selected ).toBeTruthy() // Expected undefined to be truthy
} ) )

In the last line of the code, you can see, that my tests do not detect that the player.attributes.selected is actually changed after the click. It remains to be undefined..

Answer 1

The problem is you're querying css, but not actually manipulating css in anything you posted. You want to test the component variable to be true .

After you fixture.detectChanges() you're going to want to expect( component.player.selected ).toBeTruthy() . This is assuming you have a TestBed for testing.

If you're looking to actually check the "activated" status (not selected) on your bootstrap form-group, then you'll need to apply your [ngClass]="{'selected':player.selected}" in your *ngFor loop.