@Test public void retryableCallRequest() throws InterruptedException {

  RetryableCalls retryableCalls = new RetryableCalls();
  MockWebServer server = new MockWebServer();
  Retrofit retrofit = new Retrofit.Builder()
      .baseUrl(server.url("/"))
      .addCallAdapterFactory(retryableCalls.getFactory())
      .addConverterFactory(new ToStringConverterFactory())
      .build();
  Service service = retrofit.create(Service.class);
  RetryableCall<String> call = service.getString();
  assertThat(call.request()).isNotNull();
}