@Test
  void slashIsEncodedInPathParams() throws Exception {
    server.enqueue(new MockResponse().setBody("response data"));

    String url = "http://localhost:" + server.getPort();

    TestInterface api = Feign.builder().target(TestInterface.class, url);
    api.getQueues("/");

    assertThat(server.takeRequest()).hasPath("/api/queues/%2F");
  }
Shows exception handling isn't required to coerce 204 to null or empty
core/src/test/java/feign/FeignBuilderTest.java