# Copyright (C) 2011 Google Inc. All rights reserved.
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# in the documentation and/or other materials provided with the
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class WatchListRule:
    '''A rule with instructions to do when the rule is satisified.'''
    def __init__(self, complex_definition, instructions):
        self.definitions_to_match = complex_definition
        self._instructions = instructions

    def _match_test_definitions(self, test, matching_definitions):
        if test.startswith('!'):
            return test.split('!', 1)[1] not in matching_definitions
        return test in matching_definitions

    def match(self, matching_definitions):
        for test_definition in self.definitions_to_match.split('|'):
            if '&' in test_definition:
                match_all_subgroup = True
                for test_definition_suball in test_definition.split('&'):
                    if not self._match_test_definitions(test_definition_suball, matching_definitions):
                        match_all_subgroup = False
                if match_all_subgroup:
                    return True
            elif self._match_test_definitions(test_definition, matching_definitions):
                return True
        return False

    def instructions(self):
        return self._instructions

    def remove_instruction(self, instruction):
        self._instructions.remove(instruction)
