title: How to make test case cover the statements inside pipe(map... using jest
body: <p>I am using angular. </p>
  
  <p><code>Component code</code></p>
  
  <pre><code> httpClient.post(URL, requestBody)
     .pipe(map((result) =&gt; {
        serviceCall(result);
   }));
  </code></pre>
  
  <p>How to cover code inside pipe(map using Jest test case?</p>
  
  <p>I wrote the jest test case like below but it's not covering the statements inside pipe</p>
  
  <pre><code>  spyOn(httpClient, 'post').and
      .returnValue(new Observable( observer =&gt; {
      observer.next([]);
    }));
  </code></pre>