2000-08-14 22:13:23 -03:00
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class Delegator:
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def __init__(self, delegate=None):
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self.delegate = delegate
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2013-06-30 19:37:05 -03:00
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self.__cache = set()
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2016-05-15 23:06:49 -03:00
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# Cache is used to only remove added attributes
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# when changing the delegate.
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2000-08-14 22:13:23 -03:00
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def __getattr__(self, name):
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attr = getattr(self.delegate, name) # May raise AttributeError
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setattr(self, name, attr)
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2013-06-30 19:37:05 -03:00
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self.__cache.add(name)
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2000-08-14 22:13:23 -03:00
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return attr
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def resetcache(self):
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2016-05-15 23:06:49 -03:00
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"Removes added attributes while leaving original attributes."
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2019-06-03 01:39:32 -03:00
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# Function is really about resetting delegator dict
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2016-05-15 23:06:49 -03:00
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# to original state. Cache is just a means
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2007-08-23 02:25:55 -03:00
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for key in self.__cache:
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2000-08-14 22:13:23 -03:00
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try:
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delattr(self, key)
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except AttributeError:
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pass
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self.__cache.clear()
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def setdelegate(self, delegate):
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2016-05-15 23:06:49 -03:00
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"Reset attributes and change delegate."
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2000-08-14 22:13:23 -03:00
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self.resetcache()
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self.delegate = delegate
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2016-05-15 23:06:49 -03:00
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if __name__ == '__main__':
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from unittest import main
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main('idlelib.idle_test.test_delegator', verbosity=2)
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