/**
  * Tests calling a missing image operation plugin.
  */
 function testMissingOperation()
 {
     // Test that the image factory is set to use the GD toolkit.
     $this->assertEqual($this->imageFactory->getToolkitId(), 'gd', 'The image factory is set to use the \'gd\' image toolkit.');
     // An image file that will be tested.
     $file = 'image-test.png';
     // Load up a fresh image.
     $image = $this->imageFactory->get(drupal_get_path('module', 'simpletest') . '/files/' . $file);
     if (!$image->isValid()) {
         $this->fail(String::format('Could not load image %file.', array('%file' => $file)));
     }
     // Try perform a missing toolkit operation.
     $this->assertFalse($image->apply('missing_op', array()), 'Calling a missing image toolkit operation plugin fails.');
 }