@Test
  public void reasonPhraseIsOptional() throws IOException, InterruptedException {
    server.enqueue(new MockResponse().setStatus("HTTP/1.1 " + 200));

    TestInterface api =
        newBuilder().target(TestInterface.class, "http://localhost:" + server.getPort());

    Response response = api.post("foo");

    assertThat(response.status()).isEqualTo(200);
    assertThat(response.reason()).isNullOrEmpty();
  }
Some client implementation tests should override this test if the PATCH operation is
unsupported.
core/src/test/java/feign/client/AbstractClientTest.java