protected function visitClass(Node\Stmt\Class_ $class)
    {
        $this->testClass = false;

        $parent = $class->extends;

        if (empty($parent)) {
            // No ancestry
            // Treat the class as a test case class if the name
            // of the parent class ends with "TestCase".

            if (substr($class->name, -8) == 'TestCase') {
                $this->testClass = true;
            }
        } else {
            // Ancestry
            // Treat the class as a test case class if the name
            // of the parent class equals to "PHPUnit_Framework_TestCase".

            if ((string) $parent === 'PHPUnit_Framework_TestCase') {
                $this->testClass = true;
            }
        }
    }