Question

我正在为Angular 4组件编写测试，这是一个登录表单。可以通过单击＆＃34;提交＆＃34;提交表单。按钮或在任何输入字段中按Enter键。此行为由Angular表单指令决定。

我可以编写一个测试用例来验证按钮点击提交表单，但是我无法通过按键事件触发提交行为。

模板：

<form (ngSubmit)="onLoginSubmit()" #loginForm="ngForm">
<div class="form-group">
    <label for="userid">User ID</label>
    <input type="text" class="form-control" name="userid" id="userid" required
        [(ngModel)]="model.userId" #userid="ngModel">
    <div [hidden]="userid.valid || userid.untouched" class="alert alert-danger">
        User ID is required
    </div>
</div>
<div class="form-group">
    <label for="password">Password</label>
    <input type="password" class="form-control" name="password" id="password" required
        [(ngModel)]="model.password" #password="ngModel">
    <div [hidden]="password.valid || password.untouched" class="alert alert-danger">
        Password is required
    </div>
</div>
<button type="submit" class="btn btn-success" [disabled]="loginForm.form.invalid">Submit</button>

规格：

import { ComponentFixture, TestBed } from '@angular/core/testing';
import { By } from '@angular/platform-browser';
import { DebugElement, Component, ViewChild } from '@angular/core';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { Observable } from 'rxjs/Observable';

import { LoginFormComponent } from './login-form.component';
import { ILoginService } from '../../service/ILoginService';
import { IAuthService } from '../../service/IAuthService';


describe('Login Form', () => {
    let comp: LoginFormComponent;
    let fixture: ComponentFixture<LoginFormComponent>;
    let userIdElement: DebugElement;
    let passwordElement: DebugElement;
    let submitElement: DebugElement;

    beforeEach(() => {
        TestBed.configureTestingModule({
            imports: [FormsModule, ReactiveFormsModule],
            declarations: [LoginFormComponent],
            providers: [
                { provide: 'IloginService', useClass: UserServiceMock },
                { provide: 'IAuthService', useClass: MockAuthService }]
        });
        fixture = TestBed.createComponent(LoginFormComponent);

        comp = fixture.componentInstance;

        userIdElement = fixture.debugElement.query(By.css('input[name=userid]'));
        passwordElement = fixture.debugElement.query(By.css('input[name=password]'));
        submitElement = fixture.debugElement.query(By.css('button'));
    });

    describe('Submit', () => {
        let authService: IAuthService;
        let authServiceSpy: jasmine.Spy;
        let loginService: ILoginService;
        let loginServiceSpy: jasmine.Spy;

        beforeEach(() => {
            comp.model.userId = 'mock user';
            comp.model.password = 'mock password';
            comp.loginUrl = 'mock url';

            authService = fixture.debugElement.injector.get('IAuthService');
            authServiceSpy = spyOn(authService, 'login').and.returnValue(null);

            loginService = fixture.debugElement.injector.get('IloginService');
            loginServiceSpy = spyOn(loginService, 'handleLoginResult');
        });

        it('should invoke the auth and login services when submit is clicked', () => {
            submitElement.nativeElement.click();
        });

        xit('should submit the form on enter key pressed in userId input', () => {
            userIdElement.nativeElement.dispatchEvent(new KeyboardEvent('keydown', { key: 'Enter' }))
        });

        xit('should submit the form on enter key pressed in password input', () => {
            passwordElement.nativeElement.dispatchEvent(new KeyboardEvent('keydown', { key: 'Enter' }))
        });

        afterEach(() => {
            fixture.detectChanges();
            fixture.whenStable().then(() => {
                expect(authService.login).toHaveBeenCalledWith('mock user', 'mock password', 'mock url');
                expect(loginService.handleLoginResult).toHaveBeenCalled();
            });
        });
    });
});

发送点击的测试＆＃39;来自按钮的事件通过，但是从输入元素调度keydown事件的测试（当前已禁用）失败。

我可以发送一个不同的事件来触发表单的ngSubmit处理程序来触发吗？

Answer 1

尝试使用angular.module("demo", []); angular .module("demo") .controller("demoController", ["$scope", function($scope) { $scope.users = shuffleArray([{ name: "John", age: 22, value: false, color: "green" }, { name: "Leo", age: 54, value: false, color: "blue" }, { name: "Matt", age: 35, value: false, color: "red" }]); function shuffleArray(array){ for (var i = array.length - 1; i > 0; i--) { var j = Math.floor(Math.random() * (i + 1)); var temp = array[i]; array[i] = array[j]; array[j] = temp; } return array; } $scope.changeValue = function(obj){ obj.value = !obj.value; }; }])代替＆＃39; keydown`

keypress

Answer 2

（迟到的答案，但我在这里没有看到被接受的答案）仅仅调度事件是不够的，您还必须将事件发送给组件。所以在你的例子中，你只有一个表单提交，所以你需要调用：

component.onLoginSubmit();

然而，为了分离逻辑，也许有一个为你做这项工作的主机监听器：

  @HostListener('keypress.enter', ['$event'])
  keypressEnter(event: KeyboardEvent) {
     // Maybe some further logic due to keys? Validation?
     this.onLoginSubmit();
  }

然后在你的测试中你还必须调用：

component.keypressEnter(new KeyboardEvent('keypress', { key: 'Enter' }));

最后一个 fixture.detectChanges() 将完成占空比。

单独调用 dispatch 事件是行不通的。

Answer 3

尝试获取表单元素并调用triggerEventHandler，以触发提交事件

let formElement: DebugElement;
formElement= fixture.debugElement.query(By.css('form'));
formElement.triggerEventHandler('ngSubmit', null);

在Angular单元测试中使用enter键提交表单

3 个答案: