$file = 'none.php';
if(is_file($file) && is_readable($file)){
    $time = filemtime($file);
}

结果发现 @ 做 抑制错误,但是我们的自定义错误处理程序忽略了这个事实。自定义错误处理程序仍会为隐藏的错误调用。

因此,我们的自定义错误处理程序必须进行调整以允许这样做。

旧自定义错误处理程序的摘录:

 public static function shouldIgnoreThisError(array $error)
 {
    // Stupid PHP still raises a E_WARNING when deleting a non-existing file
    // or directory, even with the @ operator. Sigh!
    $regexs = array(
       '/unlink\(.*\.cache\)\: No such file or directory/i',
       '/mkdir\(\)\: File exists/',
       '/.cache\)\: failed to open stream/',
    );

    foreach ($regexs as $regex) {
        if (preg_match($regex, $error['text'])) {
            return true;
        }
    }

    return false;
 }

当我明白这一点后,同样的函数被重写了:

 public static function shouldIgnoreThisError(array $error)
 {
    /**
     * If you have set a custom error handler function with set_error_handler()
     * then it will still get called, but this custom error handler can (and
     * should) call error_reporting() which will return 0 when the call that
     * triggered the error was preceded by an @.
     *
     * http://php.net/manual/en/language.operators.errorcontrol.php
     */
    return !error_reporting();
 }