source: class RetryableCallsTest {
  
    @Test public void retryableCallRequest() throws InterruptedException {
  
target:     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();
    }
  
  }