private MockResponse buildMockResponseWithHeaderLocation(String redirectPath) {
    return new MockResponse()
        .setResponseCode(302)
        .addHeader("location", "http://localhost:" + server.getPort() + redirectPath);
  }
Tests client-specific behavior, such as ensuring Content-Length is sent when specified.
httpclient/src/test/java/feign/httpclient/ApacheHttpClientTest.java