title: PhpStorm: extract() identifying variables
body: <p>Does anyone know whether there is a setting in PhpStorm that can trigger identifying variables generated using <code>extract()</code> function?</p>
  
  <p>Example would be something like the following:</p>
  
  <pre><code>/**
   * @return array
   */
  protected function orderSet() : array
  {
      //...
  
      return [
          'colour' =&gt; $colour,
          'green' =&gt; $green,
          'orange' =&gt; $orange
      ];
  }
  
  
  /**
   * @test
   */
  public function returns_correct_attribute_names()
  {
      $params = $this-&gt;orderSet();
      extract($params);
  
      $this-&gt;assertEquals(
          'Colour',
          $colour-&gt;name
      );
  }
  </code></pre>
  
  <p>At the moment any variable that's been extracted in the test is highlighted (unrecognised), but perhaps there is a setting that can change this behaviour?</p>