public function execute()
    {
        $cmd = $this->executable;

        if ($this->args !== null) {
            $cmd .= " {$this->args}";
        }
        if ($this->config !== null) {
            $cmd .= " -c '{$this->config}'";
        }
        if ($this->directory !== null) {
            $dirPath = $this->phpci->buildPath . DIRECTORY_SEPARATOR . $this->directory;
            $cmd .= " -d '{$dirPath}'";
        }
        chdir($this->phpci->buildPath);
        $output = '';
        $status = true;
        exec($cmd, $output);

        if (count(preg_grep("/Success \(/", $output)) == 0) {
            $status = false;
            $this->phpci->log($output);
        }
        if (count($output) == 0) {
            $status = false;
            $this->phpci->log(Lang::get('no_tests_performed'));
        }
        
        return $status;
    }