@Test
public void shouldForward() throws InterruptedException {

  final ExecutorService mockSut = GrpcContextUtil.currentContextExecutorService(executorService);
  mockSut.shutdown();
  verify(executorService).shutdown();
  mockSut.shutdownNow();
  verify(executorService).shutdownNow();
  mockSut.isShutdown();
  verify(executorService).isShutdown();
  mockSut.isTerminated();
  verify(executorService).isTerminated();
  mockSut.awaitTermination(7, TimeUnit.HOURS);
  verify(executorService).awaitTermination(7, TimeUnit.HOURS);
}