[Feature request] Mocking for Call<Void> responses

Given the following example:

public interface Example {
	@GET
	public Call<MyObject> getThingy();
        @POST
        public Call<Void> postThingy();
}

to mock the response for the GET request, I do something like:

MyObject object = new MyObject();
Call<MyObject> response = Calls.response(object);
when(example.getThingy()).thenReturn(response);

But when I try to do the same for the second request

Constructor<Void> voidConstructor = Void.class.getDeclaredConstructor();
voidConstructor.setAccessible(true);
Void voidMock = voidConstructor.newInstance();
Call<Void> response = Calls.response(voidMock);
when(example.postThingy()).thenReturn(response);

NPE is thrown (I tried some other approaches to this, but every time NPE was thrown; this was the one most likely to work) at response.enqueue

        response.enqueue(new Callback<Void>() {
            @Override
            public void onResponse(Call<Void> call, Response<Void> response) {
               //Do something
            }

            @Override
            public void onFailure(Call<Void> call, Throwable t) {
                //Do something
            }
        });

Is it possible for Call<Void> response = Calls.response(voidMock); to return a response that will not throw a NPE? (or maybe there is another way to test the postThingy() method; I didn’t manage to find any, since there is scarce info on how to mock Call<> responses… took me a lot of time to find what I wrote above).

[jaredculp]

Thanks @NightlyNexus, looks like the compiler just needed a bit of help:

interface Client {
  Call<Void> request();
}

when(client.request()).thenReturn(Calls.response((Void) null));

[NightlyNexus]

@jaredculp make sure you’re linking to the correct method. https://github.com/square/retrofit/blob/5c2f505a974d84763b3c2279128351b8a73a3e2d/retrofit-mock/src/main/java/retrofit2/mock/Calls.java#L37 and not https://github.com/square/retrofit/blob/5c2f505a974d84763b3c2279128351b8a73a3e2d/retrofit-mock/src/main/java/retrofit2/mock/Calls.java#L41