angular-docs-cn/modules/@angular/common/test/directives/ng_switch_spec.ts

191 lines
6.3 KiB
TypeScript

/**
* @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 {CommonModule} from '@angular/common';
import {Attribute, Component, Directive} from '@angular/core';
import {ComponentFixture, TestBed} from '@angular/core/testing';
import {expect} from '@angular/platform-browser/testing/matchers';
export function main() {
describe('NgSwitch', () => {
let fixture: ComponentFixture<any>;
function getComponent(): TestComponent { return fixture.componentInstance; }
function detectChangesAndExpectText(text: string): void {
fixture.detectChanges();
expect(fixture.nativeElement).toHaveText(text);
}
afterEach(() => { fixture = null; });
beforeEach(() => {
TestBed.configureTestingModule({
declarations: [TestComponent],
imports: [CommonModule],
});
});
describe('switch value changes', () => {
it('should switch amongst when values', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchCase="\'a\'">when a</li>' +
'<li *ngSwitchCase="\'b\'">when b</li>' +
'</ul>';
fixture = createTestComponent(template);
detectChangesAndExpectText('');
getComponent().switchValue = 'a';
detectChangesAndExpectText('when a');
getComponent().switchValue = 'b';
detectChangesAndExpectText('when b');
});
it('should switch amongst when values with fallback to default', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchCase="\'a\'">when a</li>' +
'<li *ngSwitchDefault>when default</li>' +
'</ul>';
fixture = createTestComponent(template);
detectChangesAndExpectText('when default');
getComponent().switchValue = 'a';
detectChangesAndExpectText('when a');
getComponent().switchValue = 'b';
detectChangesAndExpectText('when default');
getComponent().switchValue = 'c';
detectChangesAndExpectText('when default');
});
it('should support multiple whens with the same value', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchCase="\'a\'">when a1;</li>' +
'<li *ngSwitchCase="\'b\'">when b1;</li>' +
'<li *ngSwitchCase="\'a\'">when a2;</li>' +
'<li *ngSwitchCase="\'b\'">when b2;</li>' +
'<li *ngSwitchDefault>when default1;</li>' +
'<li *ngSwitchDefault>when default2;</li>' +
'</ul>';
fixture = createTestComponent(template);
detectChangesAndExpectText('when default1;when default2;');
getComponent().switchValue = 'a';
detectChangesAndExpectText('when a1;when a2;');
getComponent().switchValue = 'b';
detectChangesAndExpectText('when b1;when b2;');
});
});
describe('when values changes', () => {
it('should switch amongst when values', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchCase="when1">when 1;</li>' +
'<li *ngSwitchCase="when2">when 2;</li>' +
'<li *ngSwitchDefault>when default;</li>' +
'</ul>';
fixture = createTestComponent(template);
getComponent().when1 = 'a';
getComponent().when2 = 'b';
getComponent().switchValue = 'a';
detectChangesAndExpectText('when 1;');
getComponent().switchValue = 'b';
detectChangesAndExpectText('when 2;');
getComponent().switchValue = 'c';
detectChangesAndExpectText('when default;');
getComponent().when1 = 'c';
detectChangesAndExpectText('when 1;');
getComponent().when1 = 'd';
detectChangesAndExpectText('when default;');
});
});
describe('corner cases', () => {
it('should not create the default case if another case matches', () => {
const log: string[] = [];
@Directive({selector: '[test]'})
class TestDirective {
constructor(@Attribute('test') test: string) { log.push(test); }
}
const template = '<div [ngSwitch]="switchValue">' +
'<div *ngSwitchCase="\'a\'" test="aCase"></div>' +
'<div *ngSwitchDefault test="defaultCase"></div>' +
'</div>';
TestBed.configureTestingModule({declarations: [TestDirective]});
TestBed.overrideComponent(TestComponent, {set: {template: template}})
.createComponent(TestComponent);
const fixture = TestBed.createComponent(TestComponent);
fixture.componentInstance.switchValue = 'a';
fixture.detectChanges();
expect(log).toEqual(['aCase']);
});
it('should create the default case if there is no other case', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchDefault>when default1;</li>' +
'<li *ngSwitchDefault>when default2;</li>' +
'</ul>';
fixture = createTestComponent(template);
detectChangesAndExpectText('when default1;when default2;');
});
it('should allow defaults before cases', () => {
const template = '<ul [ngSwitch]="switchValue">' +
'<li *ngSwitchDefault>when default1;</li>' +
'<li *ngSwitchDefault>when default2;</li>' +
'<li *ngSwitchCase="\'a\'">when a1;</li>' +
'<li *ngSwitchCase="\'b\'">when b1;</li>' +
'<li *ngSwitchCase="\'a\'">when a2;</li>' +
'<li *ngSwitchCase="\'b\'">when b2;</li>' +
'</ul>';
fixture = createTestComponent(template);
detectChangesAndExpectText('when default1;when default2;');
getComponent().switchValue = 'a';
detectChangesAndExpectText('when a1;when a2;');
getComponent().switchValue = 'b';
detectChangesAndExpectText('when b1;when b2;');
});
});
});
}
@Component({selector: 'test-cmp', template: ''})
class TestComponent {
switchValue: any = null;
when1: any = null;
when2: any = null;
}
function createTestComponent(template: string): ComponentFixture<TestComponent> {
return TestBed.overrideComponent(TestComponent, {set: {template: template}})
.createComponent(TestComponent);
}