Angular2 mocking injectable service

Question

I use Angular 2 Karma-Jasmine. I have AService,

it("test", () => {
    let x:any = function1('value', aService);
    expect(x).toEqual("value1");
});

Now AService has getA() method, and function1 used getA() method. I want mock AService.getA method?.

Please tell me best ways for mocking AService ?

Are you using dependency injection in your test? please provide a bigger example. — Supamiu, Oct 04 '16 at 19:34
I havent example deat @Supamiu,I want learn best ways for mocking in angular2-jasmine-karma. My function1 is static,to whcih passed AServcie,there is no injection. — emanuel07, Oct 04 '16 at 19:38

score 1 · Accepted Answer · edited May 23 '17 at 12:09

1

If function's signature is to accept AService type

function1(value, service: AService) {}

then you need to make sure that the mock is compatible with AService. If AService only has one method getA, then you really only need to do

let mockA = {
  getA: () => {
    // mock implementation
  }
}

If AService has more methods than just the getA and you don't want to have to implement that, then you can "cast" the mock to type AService.

let mock = <AService>{ same as above }

Or if the function1 parameter is not typed as AService, then you can really pass anything it.

See Also:

edited May 23 '17 at 12:09

Community

answered Oct 05 '16 at 01:36

Paul Samsotha

My AService has other methods too. How to do in that case? Please edit answer for that case. – emanuel07 Oct 05 '16 at 04:47
Thank you,probably it is a best solution for mocking? – emanuel07 Oct 05 '16 at 05:48
I don't know about _best_ solution, but I do it all the time. – Paul Samsotha Oct 05 '16 at 05:58
Thank you,and last question-my getA() has return type,where it I must place in ? let mockA = { getA: () => { // mock implementation } } – emanuel07 Oct 05 '16 at 06:24
`getA: (): ReturnType => {}`. Though most of the time TypeScript can figure it out just by what you return in the method body. – Paul Samsotha Oct 05 '16 at 06:27

1 Answers1