angular-docs-cn/packages/core/test/component_fixture_spec.ts

/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */

import {Component, Injectable, Input} from '@angular/core';
import {async, ComponentFixtureAutoDetect, ComponentFixtureNoNgZone, TestBed, withModule} from '@angular/core/testing';
import {dispatchEvent} from '@angular/platform-browser/testing/src/browser_util';
import {expect} from '@angular/platform-browser/testing/src/matchers';

@Component({selector: 'simple-comp', template: `<span>Original {{simpleBinding}}</span>`})
@Injectable()
class SimpleComp {
  simpleBinding: string;
  constructor() {
    this.simpleBinding = 'Simple';
  }
}

@Component({
  selector: 'my-if-comp',
  template: `MyIf(<span *ngIf="showMore">More</span>)`,
})
@Injectable()
class MyIfComp {
  showMore: boolean = false;
}

@Component({selector: 'autodetect-comp', template: `<span (click)='click()'>{{text}}</span>`})
class AutoDetectComp {
  text: string = '1';

  click() {
    this.text += '1';
  }
}

@Component({selector: 'async-comp', template: `<span (click)='click()'>{{text}}</span>`})
class AsyncComp {
  text: string = '1';

  click() {
    Promise.resolve(null).then((_) => {
      this.text += '1';
    });
  }
}

@Component({selector: 'async-child-comp', template: '<span>{{localText}}</span>'})
class AsyncChildComp {
  localText: string = '';

  @Input()
  set text(value: string) {
    Promise.resolve(null).then((_) => {
      this.localText = value;
    });
  }
}

@Component({
  selector: 'async-change-comp',
  template: `<async-child-comp (click)='click()' [text]="text"></async-child-comp>`
})
class AsyncChangeComp {
  text: string = '1';

  click() {
    this.text += '1';
  }
}

@Component({selector: 'async-timeout-comp', template: `<span (click)='click()'>{{text}}</span>`})
class AsyncTimeoutComp {
  text: string = '1';

  click() {
    setTimeout(() => {
      this.text += '1';
    }, 10);
  }
}

@Component(
    {selector: 'nested-async-timeout-comp', template: `<span (click)='click()'>{{text}}</span>`})
class NestedAsyncTimeoutComp {
  text: string = '1';

  click() {
    setTimeout(() => {
      setTimeout(() => {
        this.text += '1';
      }, 10);
    }, 10);
  }
}

{
  describe('ComponentFixture', () => {
    beforeEach(async(() => {
      TestBed.configureTestingModule({
        declarations: [
          AutoDetectComp, AsyncComp, AsyncTimeoutComp, NestedAsyncTimeoutComp, AsyncChangeComp,
          MyIfComp, SimpleComp, AsyncChildComp
        ]
      });
    }));

    it('should auto detect changes if autoDetectChanges is called', () => {
      const componentFixture = TestBed.createComponent(AutoDetectComp);
      expect(componentFixture.ngZone).not.toBeNull();
      componentFixture.autoDetectChanges();
      expect(componentFixture.nativeElement).toHaveText('1');

      const element = componentFixture.debugElement.children[0];
      dispatchEvent(element.nativeElement, 'click');

      expect(componentFixture.isStable()).toBe(true);
      expect(componentFixture.nativeElement).toHaveText('11');
    });

    it('should auto detect changes if ComponentFixtureAutoDetect is provided as true',
       withModule({providers: [{provide: ComponentFixtureAutoDetect, useValue: true}]}, () => {
         const componentFixture = TestBed.createComponent(AutoDetectComp);
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');

         expect(componentFixture.nativeElement).toHaveText('11');
       }));

    it('should signal through whenStable when the fixture is stable (autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(AsyncComp);
         componentFixture.autoDetectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become stable
         // before checking for new value.
         expect(componentFixture.isStable()).toBe(false);
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should signal through isStable when the fixture is stable (no autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(AsyncComp);

         componentFixture.detectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become stable
         // before checking.
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should wait for macroTask(setTimeout) while checking for whenStable ' +
           '(autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(AsyncTimeoutComp);
         componentFixture.autoDetectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become
         // stable before checking for new value.
         expect(componentFixture.isStable()).toBe(false);
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should wait for macroTask(setTimeout) while checking for whenStable ' +
           '(no autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(AsyncTimeoutComp);
         componentFixture.detectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become
         // stable before checking for new value.
         expect(componentFixture.isStable()).toBe(false);
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should wait for nested macroTasks(setTimeout) while checking for whenStable ' +
           '(autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(NestedAsyncTimeoutComp);

         componentFixture.autoDetectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become
         // stable before checking for new value.
         expect(componentFixture.isStable()).toBe(false);
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should wait for nested macroTasks(setTimeout) while checking for whenStable ' +
           '(no autoDetectChanges)',
       async(() => {
         const componentFixture = TestBed.createComponent(NestedAsyncTimeoutComp);
         componentFixture.detectChanges();
         expect(componentFixture.nativeElement).toHaveText('1');

         const element = componentFixture.debugElement.children[0];
         dispatchEvent(element.nativeElement, 'click');
         expect(componentFixture.nativeElement).toHaveText('1');

         // Component is updated asynchronously. Wait for the fixture to become
         // stable before checking for new value.
         expect(componentFixture.isStable()).toBe(false);
         componentFixture.whenStable().then((waited) => {
           expect(waited).toBe(true);
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('11');
         });
       }));

    it('should stabilize after async task in change detection (autoDetectChanges)', async(() => {
         const componentFixture = TestBed.createComponent(AsyncChangeComp);

         componentFixture.autoDetectChanges();
         componentFixture.whenStable().then((_) => {
           expect(componentFixture.nativeElement).toHaveText('1');

           const element = componentFixture.debugElement.children[0];
           dispatchEvent(element.nativeElement, 'click');

           componentFixture.whenStable().then((_) => {
             expect(componentFixture.nativeElement).toHaveText('11');
           });
         });
       }));

    it('should stabilize after async task in change detection(no autoDetectChanges)', async(() => {
         const componentFixture = TestBed.createComponent(AsyncChangeComp);
         componentFixture.detectChanges();
         componentFixture.whenStable().then((_) => {
           // Run detectChanges again so that stabilized value is reflected in the
           // DOM.
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('1');

           const element = componentFixture.debugElement.children[0];
           dispatchEvent(element.nativeElement, 'click');
           componentFixture.detectChanges();

           componentFixture.whenStable().then((_) => {
             // Run detectChanges again so that stabilized value is reflected in
             // the DOM.
             componentFixture.detectChanges();
             expect(componentFixture.nativeElement).toHaveText('11');
           });
         });
       }));

    describe('No NgZone', () => {
      beforeEach(() => {
        TestBed.configureTestingModule(
            {providers: [{provide: ComponentFixtureNoNgZone, useValue: true}]});
      });

      it('calling autoDetectChanges raises an error', () => {
        const componentFixture = TestBed.createComponent(SimpleComp);
        expect(() => {
          componentFixture.autoDetectChanges();
        }).toThrowError(/Cannot call autoDetectChanges when ComponentFixtureNoNgZone is set/);
      });

      it('should instantiate a component with valid DOM', async(() => {
           const componentFixture = TestBed.createComponent(SimpleComp);

           expect(componentFixture.ngZone).toBeNull();
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('Original Simple');
         }));

      it('should allow changing members of the component', async(() => {
           const componentFixture = TestBed.createComponent(MyIfComp);

           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('MyIf()');

           componentFixture.componentInstance.showMore = true;
           componentFixture.detectChanges();
           expect(componentFixture.nativeElement).toHaveText('MyIf(More)');
         }));
    });
  });
}