angular-docs-cn/packages/core/test/acceptance/styling_spec.ts

/**
 * @license
 * Copyright Google Inc. 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, ComponentFactoryResolver, ComponentRef, Directive, ElementRef, HostBinding, Input, NgModule, ViewChild, ViewContainerRef} from '@angular/core';
import {TestBed} from '@angular/core/testing';
import {expect} from '@angular/platform-browser/testing/src/matchers';
import {ivyEnabled, onlyInIvy} from '@angular/private/testing';

describe('acceptance integration tests', () => {
  onlyInIvy('map-based [style] and [class] bindings are not supported in VE')
      .it('should render host bindings on the root component', () => {
        @Component({template: '...'})
        class MyApp {
          @HostBinding('style') myStylesExp = {};
          @HostBinding('class') myClassesExp = {};
        }

        TestBed.configureTestingModule({declarations: [MyApp]});
        const fixture = TestBed.createComponent(MyApp);
        const element = fixture.nativeElement;
        fixture.detectChanges();

        const component = fixture.componentInstance;
        component.myStylesExp = {width: '100px'};
        component.myClassesExp = 'foo';
        fixture.detectChanges();

        expect(element.style['width']).toEqual('100px');
        expect(element.classList.contains('foo')).toBeTruthy();

        component.myStylesExp = {width: '200px'};
        component.myClassesExp = 'bar';
        fixture.detectChanges();

        expect(element.style['width']).toEqual('200px');
        expect(element.classList.contains('foo')).toBeFalsy();
        expect(element.classList.contains('bar')).toBeTruthy();
      });

  it('should render host class and style on the root component', () => {
    @Component({template: '...', host: {class: 'foo', style: 'color: red'}})
    class MyApp {
    }

    TestBed.configureTestingModule({declarations: [MyApp]});
    const fixture = TestBed.createComponent(MyApp);
    const element = fixture.nativeElement;
    fixture.detectChanges();

    expect(element.style['color']).toEqual('red');
    expect(element.classList.contains('foo')).toBeTruthy();
  });

  it('should combine the inherited static styles of a parent and child component', () => {
    @Component({template: '...', host: {'style': 'width:100px; height:100px;'}})
    class ParentCmp {
    }

    @Component({template: '...', host: {'style': 'width:200px; color:red'}})
    class ChildCmp extends ParentCmp {
    }

    TestBed.configureTestingModule({declarations: [ChildCmp]});
    const fixture = TestBed.createComponent(ChildCmp);
    fixture.detectChanges();

    const element = fixture.nativeElement;
    if (ivyEnabled) {
      expect(element.style['height']).toEqual('100px');
    }
    expect(element.style['width']).toEqual('200px');
    expect(element.style['color']).toEqual('red');
  });

  it('should combine the inherited static classes of a parent and child component', () => {
    @Component({template: '...', host: {'class': 'foo bar'}})
    class ParentCmp {
    }

    @Component({template: '...', host: {'class': 'foo baz'}})
    class ChildCmp extends ParentCmp {
    }

    TestBed.configureTestingModule({declarations: [ChildCmp]});
    const fixture = TestBed.createComponent(ChildCmp);
    fixture.detectChanges();

    const element = fixture.nativeElement;
    if (ivyEnabled) {
      expect(element.classList.contains('bar')).toBeTruthy();
    }
    expect(element.classList.contains('foo')).toBeTruthy();
    expect(element.classList.contains('baz')).toBeTruthy();
  });

  it('should not cause problems if detectChanges is called when a property updates', () => {
    /**
     * Angular Material CDK Tree contains a code path whereby:
     *
     * 1. During the execution of a template function in which **more than one** property is
     * updated in a row.
     * 2. A property that **is not the last property** is updated in the **original template**:
     *   - That sets up a new observable and subscribes to it
     *   - The new observable it sets up can emit synchronously.
     *   - When it emits, it calls `detectChanges` on a `ViewRef` that it has a handle to
     *   - That executes a **different template**, that has host bindings
     *     - this executes `setHostBindings`
     *     - Inside of `setHostBindings` we are currently updating the selected index **global
     *       state** via `setActiveHostElement`.
     * 3. We attempt to update the next property in the **original template**.
     *  - But the selected index has been altered, and we get errors.
     */

    @Component({
      selector: 'child',
      template: `...`,
    })
    class ChildCmp {
    }

    @Component({
      selector: 'parent',
      template: `
        <div>
          <div #template></div>
          <p>{{prop}}</p>
          <p>{{prop2}}</p>
        </div>
      `,
      host: {
        '[style.color]': 'color',
      },
    })
    class ParentCmp {
      private _prop = '';

      @ViewChild('template', {read: ViewContainerRef})
      vcr: ViewContainerRef = null !;

      private child: ComponentRef<ChildCmp> = null !;

      @Input()
      set prop(value: string) {
        // Material CdkTree has at least one scenario where setting a property causes a data source
        // to update, which causes a synchronous call to detectChanges().
        this._prop = value;
        if (this.child) {
          this.child.changeDetectorRef.detectChanges();
        }
      }

      get prop() { return this._prop; }

      @Input()
      prop2 = 0;

      ngAfterViewInit() {
        const factory = this.componentFactoryResolver.resolveComponentFactory(ChildCmp);
        this.child = this.vcr.createComponent(factory);
      }

      constructor(private componentFactoryResolver: ComponentFactoryResolver) {}
    }

    @Component({
      template: `<parent [prop]="prop" [prop2]="prop2"></parent>`,
    })
    class App {
      prop = 'a';
      prop2 = 1;
    }

    @NgModule({
      entryComponents: [ChildCmp],
      declarations: [ChildCmp],
    })
    class ChildCmpModule {
    }

    TestBed.configureTestingModule({declarations: [App, ParentCmp], imports: [ChildCmpModule]});
    const fixture = TestBed.createComponent(App);
    fixture.detectChanges();

    fixture.componentInstance.prop = 'b';
    fixture.componentInstance.prop2 = 2;
    fixture.detectChanges();
  });

  it('should render inline style and class attribute values on the element before a directive is instantiated',
     () => {
       @Component({
         template: `
        <div directive-expecting-styling style="width:200px" class="abc xyz"></div>
      `
       })
       class Cmp {
       }

       @Directive({selector: '[directive-expecting-styling]'})
       class DirectiveExpectingStyling {
         constructor(elm: ElementRef) {
           const native = elm.nativeElement;
           native.setAttribute('data-captured-width', native.style.width);
           native.setAttribute('data-captured-classes', native.className);
         }
       }

       TestBed.configureTestingModule({declarations: [Cmp, DirectiveExpectingStyling]});
       const fixture = TestBed.createComponent(Cmp);
       fixture.detectChanges();

       const element = fixture.nativeElement.querySelector('div');
       expect(element.style.width).toEqual('200px');
       expect(element.getAttribute('data-captured-width')).toEqual('200px');
       expect(element.className.trim()).toEqual('abc xyz');
       expect(element.getAttribute('data-captured-classes')).toEqual('abc xyz');
     });

  it('should only render the same initial styling values once before a directive runs', () => {
    @Component({
      template: `
        <div directive-expecting-styling style="width:200px" class="abc"></div>
      `
    })
    class Cmp {
    }

    @Directive({selector: '[directive-expecting-styling]'})
    class DirectiveExpectingStyling {
      constructor(elm: ElementRef) {
        const native = elm.nativeElement;
        native.style.width = '300px';
        native.classList.remove('abc');
      }
    }

    TestBed.configureTestingModule({declarations: [Cmp, DirectiveExpectingStyling]});
    const fixture = TestBed.createComponent(Cmp);
    fixture.detectChanges();

    const element = fixture.nativeElement.querySelector('div');
    expect(element.style.width).toEqual('300px');
    expect(element.classList.contains('abc')).toBeFalsy();
  });

  it('should render styling for parent and sub-classed components in order', () => {
    @Component({
      template: `
        <child-and-parent-cmp></child-and-parent-cmp>
      `
    })
    class MyApp {
    }

    @Component({template: '...'})
    class ParentCmp {
      @HostBinding('style.width') width1 = '100px';
      @HostBinding('style.height') height1 = '100px';
      @HostBinding('style.opacity') opacity1 = '0.5';
    }

    @Component({selector: 'child-and-parent-cmp', template: '...'})
    class ChildCmp extends ParentCmp {
      @HostBinding('style.width') width2 = '200px';
      @HostBinding('style.height') height2 = '200px';
    }

    TestBed.configureTestingModule({declarations: [MyApp, ParentCmp, ChildCmp]});
    const fixture = TestBed.createComponent(MyApp);
    const element = fixture.nativeElement;
    fixture.detectChanges();

    const childElement = element.querySelector('child-and-parent-cmp');
    expect(childElement.style.width).toEqual('200px');
    expect(childElement.style.height).toEqual('200px');
    expect(childElement.style.opacity).toEqual('0.5');
  });

  onlyInIvy('[style.prop] and [class.name] prioritization is a new feature')
      .it('should prioritize styling present in the order of directive hostBinding evaluation, but consider sub-classed directive styling to be the most important',
          () => {
            const log: string[] = [];

            @Component({template: '<div child-dir sibling-dir></div>'})
            class MyApp {
            }

            @Directive({selector: '[parent-dir]'})
            class ParentDir {
              @HostBinding('style.width')
              get width1() { return '100px'; }

              @HostBinding('style.height')
              get height1() { return '100px'; }

              @HostBinding('style.color')
              get color1() { return 'red'; }
            }

            @Directive({selector: '[child-dir]'})
            class ChildDir extends ParentDir {
              @HostBinding('style.width')
              get width2() { return '200px'; }

              @HostBinding('style.height')
              get height2() { return '200px'; }
            }

            @Directive({selector: '[sibling-dir]'})
            class SiblingDir {
              @HostBinding('style.width')
              get width3() { return '300px'; }

              @HostBinding('style.height')
              get height3() { return '300px'; }

              @HostBinding('style.opacity')
              get opacity3() { return '0.5'; }

              @HostBinding('style.color')
              get color1() { return 'blue'; }
            }

            TestBed.configureTestingModule(
                {declarations: [MyApp, ParentDir, ChildDir, SiblingDir]});
            const fixture = TestBed.createComponent(MyApp);
            const element = fixture.nativeElement;
            fixture.detectChanges();

            const childElement = element.querySelector('div');

            // width/height values were set in all directives, but the sub-class directive
            // (ChildDir)
            // had priority over the parent directive (ParentDir) which is why its value won. It
            // also
            // won over Dir because the SiblingDir directive was evaluated later on.
            expect(childElement.style.width).toEqual('200px');
            expect(childElement.style.height).toEqual('200px');

            // ParentDir styled the color first before Dir
            expect(childElement.style.color).toEqual('red');

            // Dir was the only directive to style opacity
            expect(childElement.style.opacity).toEqual('0.5');
          });

  it('should ensure that static classes are assigned to ng-container elements and picked up for content projection',
     () => {
       @Component({
         template: `
            <project>
              outer
              <ng-container class="inner">
                inner
              </ng-container>
            </project>
          `
       })
       class MyApp {
       }

       @Component({
         selector: 'project',
         template: `
            <div class="outer-area">
              <ng-content></ng-content>
            </div>
            <div class="inner-area">
              <ng-content select=".inner"></ng-content>
            </div>
          `
       })
       class ProjectCmp {
       }

       TestBed.configureTestingModule({declarations: [MyApp, ProjectCmp]});
       const fixture = TestBed.createComponent(MyApp);
       const element = fixture.nativeElement;
       fixture.detectChanges();

       const inner = element.querySelector('.inner-area');
       expect(inner.textContent.trim()).toEqual('inner');
       const outer = element.querySelector('.outer-area');
       expect(outer.textContent.trim()).toEqual('outer');
     });

  it('should allow class-bindings to be placed on ng-container elements', () => {
    @Component({
      template: `
        <ng-container [class.foo]="true" dir-that-adds-other-classes>...</ng-container>
      `
    })
    class MyApp {
    }

    @Directive({selector: '[dir-that-adds-other-classes]'})
    class DirThatAddsOtherClasses {
      @HostBinding('class.other-class') bool = true;
    }

    TestBed.configureTestingModule({declarations: [MyApp, DirThatAddsOtherClasses]});
    expect(() => {
      const fixture = TestBed.createComponent(MyApp);
      fixture.detectChanges();
    }).not.toThrow();
  });
});