Just a heads up: I know Angular2 is still in alpha and undergoing frequent changes.
I am currently working with Angular2 and facing an issue with testing an injectable service that has a dependency on http. I want to test this service using a mock backend. The service functions correctly when the application starts, but I am struggling with writing the test and getting the mock backend to provide a response. Is there something obvious in the test setup or implementation that I might be overlooking?
service/core.ts:
import { Injectable } from 'angular2/angular2';
import { Http } from 'angular2/http';
@Injectable()
export class CoreService {
constructor(public http:Http) {}
getStatus() {
return this.http.get('/api/status')
.toRx()
.map(res => res.json());
}
}
service/core_spec.ts:
import {
AsyncTestCompleter,
TestComponentBuilder,
By,
beforeEach,
ddescribe,
describe,
el,
expect,
iit,
inject,
it,
xit
} from 'angular2/test';
import { MockBackend, MockConnection, BaseRequestOptions, Http, Response } from 'angular2/http';
import { Injector, bind } from 'angular2/angular2';
import { ObservableWrapper } from 'angular2/src/core/facade/async'
import { CoreService } from 'public/services/core'
export function main() {
describe('public/services/core', () => {
let backend: MockBackend;
let response: Response;
let coreService: CoreService;
let injector: Injector;
afterEach(() => backend.verifyNoPendingRequests());
it('should get status', inject([AsyncTestCompleter], (async) => {
injector = Injector.resolveAndCreate([
BaseRequestOptions,
MockBackend,
bind(Http).toFactory((backend, options) => {
return new Http(backend, options)
}, [MockBackend, BaseRequestOptions]),
bind(CoreService).toFactory((http) => {
return new CoreService(http);
}, [Http])
]);
backend = injector.get(MockBackend);
coreService = injector.get(CoreService);
response = new Response('foo');
ObservableWrapper.subscribe<MockConnection>(backend.connections, c => {
expect(c.request.url).toBe('/api/status');
c.mockRespond(response);
});
// attempt #1: fails because res argument is undefined
coreService.getStatus().subscribe(res => {
expect(res).toBe('');
async.done();
});
// attempt #2: fails because emitter.observer is not a function
ObservableWrapper.subscribe(coreService.getStatus(), res => {
expect(res).toBe('');
async.done();
});
}));
});
}
Related: https://github.com/angular/angular/issues/3502 https://github.com/angular/angular/issues/3530