title: Testing endpoint with MultiValueMap as param
body: <p>I've got an endpoint as:</p>
  
  <pre><code>@RequestMapping(value = "/topics/{topicId}")
  public class TopicGateway {
      @PostMapping
      public void generate(@RequestParam MultiValueMap params, HttpServletResponse response) {
          reportFacade.generate(params, response);
      }
  </code></pre>
  
  <p>I would've like to create integration test for this method.
  I use rest-assured, but example with default mockMvc usage would've help me too.</p>
  
  <p>What I did right now is just:</p>
  
  <pre><code>given()
      .pathParam("topicId", 1)
      // here I need to add those MultiValueMap.
      .get(BASE_PATH)
      .then()
      .statusCode(200);
  
  private MultiValueMap&lt;String, String&gt; params(){
      MultiValueMap&lt;String, String&gt; params = new LinkedMultiValueMap&lt;&gt;();
      params.add("param1", "Test");
      params.add("param2", "Another test");
      params.add("param3", "123");
      params.add("param4", "456");
      return params;
  }
  </code></pre>
  
  <p>I tried: .<code>formParameters(params())</code> , but seems not working. </p>