title: PHPUnit error "undefined index : HTTP_HOST"
body: <p>I have declared a HTTP_HOST as shown below.</p>
  
  <pre><code>public function testReadUser() {
  
      $_SERVER['HTTP_HOST'] = "x.y";
      .
      .
      .
  }
  </code></pre>
  
  <p>Inspite of this, phpunit gives undefined index error. Why is it?</p>