Errors.py 文件源码

def __init__(self, msg='', ex=None):
        """
        :param msg: error message
        :type msg: string
        :param ex: exception causing this error (optional)
        :type ex: exception
        """
        self.msg = msg
        assert not isinstance(msg, Exception)

        self.stack = []
        if ex:
            if not msg:
                self.msg = str(ex)
            if isinstance(ex, WafError):
                self.stack = ex.stack
            else:
                self.stack = traceback.extract_tb(sys.exc_info()[2])
        self.stack += traceback.extract_stack()[:-1]
        self.verbose_msg = ''.join(traceback.format_list(self.stack))