Angular 2 Unit testing: Can't resolve all parameters for Router - unit-testing

Question

I use unit testing with karma with angular 2. I added Router in my service and but when I write test case for that it through me following error.
Error: Can't resolve all parameters for Router: (?, ?, ?, ?, ?, ?, ?, ?).
here is code
spec.ts
import 'rxjs/add/operator/map';
import { Http, BaseRequestOptions, Response, ResponseOptions,ConnectionBackend } from '#angular/http';
import { MockBackend, MockConnection } from '#angular/http/testing';
import { GlobalUtils } from './global.utils';
import { Router} from '#angular/router';
import { TestBed, inject } from '#angular/core/testing';
describe('Global Utils : Meta urls API', () => {
let emptyMetaUrl = {};
let metaUrl = {
LOGIN: '/operator/login',
META_API: '/meta-api'
};
beforeEach(()=>TestBed.configureTestingModule({
providers: [
Router,
GlobalUtils,
BaseRequestOptions,
MockBackend,
{
provide: Http,
useFactory: function (backend:ConnectionBackend, defaultOptions:BaseRequestOptions) {
return new Http(backend, defaultOptions);
},
deps: [MockBackend, BaseRequestOptions]
},
]
}));
let subject:GlobalUtils = null;
let backend:MockBackend = null;
let http:Http = null;
beforeEach(inject([GlobalUtils, MockBackend, Http], (_globalUtils:GlobalUtils, mockBackend:MockBackend,_http:Http) => {
subject = _globalUtils;
backend = mockBackend;
http = _http;
}));
it('Should have get Meta urls', (done) => {
backend.connections.subscribe((connection:MockConnection)=> {
let options = new ResponseOptions({
body: JSON.stringify(metaUrl)
});
connection.mockRespond(new Response(options));
});
http
.get(subject.metaUrl)
.subscribe((response) => {
subject.getMetaUrls(); // in this routing is use
expect(GlobalUtils.saveUrl).toEqual(metaUrl);
done();
});
});
});
I used Routing in this service to navigate path.
service.ts
import {Injectable} from '#angular/core';
import { Router} from '#angular/router';
import {Http, Headers,Response} from '#angular/http';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';
#Injectable()
export class GlobalUtils {
static saveUrl = { };
head:Headers = new Headers();
hostUrl:string = 'http://192.168.0.103:8000/';
metaUrl:string = 'urls-metadata/';
// constructor declare
constructor(public _http:Http,public _router:Router) {
this.head.append('Content-Type', 'application/json');
}
/*
* this function is used for Http GET Request
* */
urlGet(url:string) {
let headers = this.head;
return this._http.get(this.hostUrl + url, {headers: headers})
.map(res => res.json())
.map((res) => {
return res;
});
}
/*
* this function is used to GET all API url
* */
getMetaUrls():any{
let url = this.metaUrl;
this.urlGet(url).subscribe(
(result) => {
console.log('result = '+JSON.stringify(result));
if (result) {
GlobalUtils.saveUrl = result;
console.log('get Meta urls response = '+ result.status)
}
},
(error)=> {
this._router.navigate(['page-error']);
console.log('get Meta urls error = '+ error.status + " data =" +JSON.stringify(error))
},
()=>{console.log('get Meta url is successfully')}
);
}
}
when I run karma start this test case failed with this error.
✖ Should have get Meta urls
Chrome 52.0.2743 (Linux 0.0.0)
Error: Can't resolve all parameters for Router: (?, ?, ?, ?, ?, ?, ?, ?).
at CompileMetadataResolver.getDependenciesMetadata (webpack:///~/#angular/compiler/bundles/compiler.umd.js:14404:0 <- config/spec-bundle.js:53297:22)
at CompileMetadataResolver.getTypeMetadata (webpack:///~/#angular/compiler/bundles/compiler.umd.js:14301:0 <- config/spec-bundle.js:53194:29)
at webpack:///~/#angular/compiler/bundles/compiler.umd.js:14448:0 <- config/spec-bundle.js:53341:44
at Array.forEach (native)
at CompileMetadataResolver.getProvidersMetadata (webpack:///~/#angular/compiler/bundles/compiler.umd.js:14428:0 <- config/spec-bundle.js:53321:22)
at CompileMetadataResolver.getNgModuleMetadata (webpack:///~/#angular/compiler/bundles/compiler.umd.js:14181:0 <- config/spec-bundle.js:53074:61)
at RuntimeCompiler._compileComponents (webpack:///~/#angular/compiler/bundles/compiler.umd.js:16803:0 <- config/spec-bundle.js:55696:50)
at RuntimeCompiler._compileModuleAndAllComponents (webpack:///~/#angular/compiler/bundles/compiler.umd.js:16747:0 <- config/spec-bundle.js:55640:40)
at RuntimeCompiler.compileModuleAndAllComponentsSync (webpack:///~/#angular/compiler/bundles/compiler.umd.js:16735:0 <- config/spec-bundle.js:55628:24)
at TestingCompilerImpl.compileModuleAndAllComponentsSync (webpack:///~/#angular/compiler/bundles/compiler-testing.umd.js:758:0 <- config/spec-bundle.js:38833:36)

Answer 1

If you don't care to do any actual routing in the test, you can just create a mock for it
let mockRouter = {
navigate: jasmine.createSpy('navigate')
}
TestBed.configureTestingModule({
providers: [
{ provide: Router, useValue: mockRouter }
]
})
Then in your test maybe you just want to make sure that the navigate method is called. You can do
expect(mockRouter.navigate).toHaveBeenCalledWith(['/router']);
If you do want to test real navigation, then you should use the RouterTestingModule to add all the router providers and directives.
import { RouterTestingModule } from '#angular/router/testing';
TestBed.configureTestingModule({
imports: [
RouterTestingModule.withRoutes([{path: '', component: BlankCmp}, {path: 'simple', component: SimpleCmp}])
]
})