RetrofitTest_getSingleUser.java

@Test
public void getSingleUserWithAsynchronousMethod() throws InterruptedException {
  User wingyplus = new User();
  CountDownLatch signal = new CountDownLatch(1);

  userService
    .getSingleUser("wingyplus")
    .enqueue(new Callback<User>() {
      @Override
      public void onResponse(Call<User> call, Response<User> response) {
        User user = response.body();

        wingyplus.setLogin(user.getLogin());
        wingyplus.setId(user.getId());
        wingyplus.setAvatarUrl(user.getAvatarUrl());
        wingyplus.setPublicGists(user.getPublicGists());
        wingyplus.setPublicRepos(user.getPublicRepos());

        signal.countDown();
      }

      @Override
      public void onFailure(Call<User> call, Throwable t) {

      }
    });

  signal.await();

  assertThat(wingyplus.getLogin(), is("wingyplus"));
  assertThat(wingyplus.getId(), is(484530));
  assertThat(wingyplus.getPublicRepos(), is(197));
  assertThat(wingyplus.getPublicGists(), is(216));
  assertThat(wingyplus.getAvatarUrl(), is("https://avatars.githubusercontent.com/u/484530?v=3"));
}