filter_collection.py

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class FilterCollection:
    """
    Collection of filters to test messages against.
    """
    def __init__(self):
        self._filters = []

    def test_message(self, message, default=False):
        """
        Test if the message matches any filter.
        :param message: message to be tested against the filters, ''Message''
        :param default: return value when there is no active filter, ''bool''
        :returns: True if the message matches any filter, ''bool''
        """
        match = default
        for f in self._filters:
            if f.is_enabled() and f.has_filter():
                if f.test_message(message):
                    return True
                else:
                    match = False
        return match

    def append(self, filter):
        self._filters.append(filter)

    def count_enabled_filters(self):
        enabled = [f for f in self._filters if f.is_enabled()]
        return len(enabled)

    def __len__(self):
        return len(self._filters)

    def __delitem__(self, index):
        del self._filters[index]