title: assertThat: how to invert containsString
body: <p>I have an assertion that checks if a string is present in the currently selected text:</p>
  
  <pre><code>import static org.junit.Assert.assertThat;
  import static org.hamcrest.Matchers.containsString;
  assertThat(latest.getText(), containsString(targetString));
  </code></pre>
  
  <p>But I can't find the right way to write an assertion that checks if a string is NOT contained in the text.</p>
  
  <p>I tried </p>
  
  <pre><code>assertThat(latest.getText(), not(containsString(targetString)));
  </code></pre>
  
  <p>but get an error </p>
  
  <pre><code>the method not(Matcher &lt;String&gt;) is undefined
  </code></pre>
  
  <p>What is the way to do this?</p>