Angular2 - 在測試中模擬RouteParams

Question

我在為Angular2組件的測試中為RouteParams依賴項注入模擬時遇到了一些麻煩。 我的一般想法是，我可能會錯過一些提供者。

測試失敗了：

Cannot resolve all parameters for 'RouteParams'(?). Make sure that all the parameters are decorated with Inject
or have valid type annotations and that 'RouteParams' is decorated with Injectable.

有誰知道問題可能是什么？

import {
  it,
  inject,
  injectAsync,
  describe,
  beforeEach,
  beforeEachProviders,
  TestComponentBuilder
} from 'angular2/testing';

import {Component, provide} from 'angular2/core';
import {BaseRequestOptions, Http} from 'angular2/http';
import {MockBackend} from 'angular2/http/testing';
import {RouteParams, ROUTER_PROVIDERS, ROUTER_PRIMARY_COMPONENT} from 'angular2/router';

// Load the implementations that should be tested
import {Home} from './home';
import {Title} from './providers/title';

describe('Home', () => {
  // provide our implementations or mocks to the dependency injector

  beforeEachProviders(() => [
    Title,
    Home,
    provide(RouteParams, { useValue: new RouteParams({ id: '1' }) }),
    BaseRequestOptions,
    MockBackend,
    provide(Http, {
        useFactory: function(backend, defaultOptions) {
            return new Http(backend, defaultOptions);
        },
        deps: [MockBackend, BaseRequestOptions]
    }),
    provide(RouteParams, {
        useFactory: function() {
            return new RouteParams({ 'id':'1' });
        }
    })
  ]);

  it('should have a title', inject([ Home ], (home) => {
    expect(home.title.value).toEqual('Angular 2');
  }));

  it('should have a http', inject([ Home ], (home) => {
    expect(!!home.http).toEqual(true);
  }));

  it('should log ngOnInit', inject([ Home ], (home) => {
    spyOn(console, 'log');
    spyOn(console, 'info');
    expect(console.log).not.toHaveBeenCalled();
    expect(console.info).not.toHaveBeenCalled();

    home.ngOnInit();
    expect(console.log).toHaveBeenCalled();
    expect(console.info).toHaveBeenCalledWith('1');
  }));

});

Answer 1

管理自己解決這個問題，你通過使用模擬RouteProvider

provide(RouteParams, { useValue: new RouteParams({ id: '1' }) })

import {
  it,
  inject,
  injectAsync,
  describe,
  beforeEach,
  beforeEachProviders,
  TestComponentBuilder
} from 'angular2/testing';

import {Component, provide} from 'angular2/core';
import {BaseRequestOptions, Http} from 'angular2/http';
import {MockBackend} from 'angular2/http/testing';
import {RouteParams, ROUTER_PROVIDERS, ROUTER_PRIMARY_COMPONENT} from 'angular2/router';

// Load the implementations that should be tested
import {Home} from './home';
import {Title} from './providers/title';

describe('Home', () => {
  // provide our implementations or mocks to the dependency injector

  beforeEachProviders(() => [
    Title,
    Home,
    provide(RouteParams, { useValue: new RouteParams({ id: '1' }) }),
    BaseRequestOptions,
    MockBackend,
    provide(Http, {
        useFactory: function(backend, defaultOptions) {
            return new Http(backend, defaultOptions);
        },
        deps: [MockBackend, BaseRequestOptions]
    })
  ]);

  it('should have a title', inject([ Home ], (home) => {
    expect(home.title.value).toEqual('Angular 2');
  }));

  it('should have a http', inject([ Home ], (home) => {
    expect(!!home.http).toEqual(true);
  }));

  it('should log ngOnInit', inject([ Home ], (home) => {
    spyOn(console, 'log');
    spyOn(console, 'info');
    expect(console.log).not.toHaveBeenCalled();
    expect(console.info).not.toHaveBeenCalled();

    home.ngOnInit();
    expect(console.log).toHaveBeenCalled();
    expect(console.info).toHaveBeenCalledWith('1');
  }));

});

Answer 2

對於那些在這里降落的人，即使他們正在使用Angular4

我只是繼續創造了一個模擬。 我想訣竅是模擬你需要的ActivatedRoute部分。 對我來說，這樣做了：

import {ActivatedRoute, ParamMap} from '@angular/router';

/**
 * Mocking the ActivatedRoute which is injected in the Component on creation.
 * This allows for easier testing as values can be set as needed.
 */
class MockActivatedRoute {
   paramMap = Observable.of(new Params());
}

/**
 * Bare bones implementation of ParamMap used in mock. Further tests can expand
 * on this implementation as needed.
 */
class Params implements ParamMap {
  keys: string[];

  private routes: {[key: string]: string|null} = {
    subject: 'foo',
    time: 'd-123-1',
    device: 'all',
    location: 'c-123'
  };

  constructor() {
    this.keys = Object.keys(this.routes);
  }

  has(name: string): boolean {
    throw new Error('Method not implemented.');
  }
  get(name: string): string|null {
    return this.routes[name];
  }
  getAll(name: string): string[] {
    throw new Error('Method not implemented.');
  }
}

然后在您的測試模塊中確保您通過真實的ActivatedRoute提供模擬服務：

providers: [
  {
    provide: ActivatedRoute,
    useValue: new MockActivatedRoute(),
  }
]

為了完成，我在組件I測試中使用它的方式：

ngOnInit() {
  this.route.paramMap
      .map((params: ParamMap) => params.get('subject') as string)
      .subscribe((subject: string) => this.subject = subject);
}