utils.py 文件源码

def __enter__(self):
        # let parent class archive filter state
        ret = super(reset_warnings, self).__enter__()

        # reset the filter to list everything
        if self._reset_filter:
            warnings.resetwarnings()
            warnings.simplefilter(self._reset_filter)

        # archive and clear the __warningregistry__ key for all modules
        # that match the 'reset' pattern.
        pattern = self._reset_registry
        if pattern:
            backup = self._orig_registry = {}
            for name, mod in list(sys.modules.items()):
                if mod is None or not pattern.match(name):
                    continue
                reg = getattr(mod, "__warningregistry__", None)
                if reg:
                    backup[name] = reg.copy()
                    reg.clear()
        return ret