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33 lines
1 KiB
Python
33 lines
1 KiB
Python
class Delegator:
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def __init__(self, delegate=None):
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self.delegate = delegate
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self.__cache = set()
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# Cache is used to only remove added attributes
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# when changing the delegate.
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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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self.__cache.add(name)
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return attr
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def resetcache(self):
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"Removes added attributes while leaving original attributes."
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# Function is really about resetting delegator dict
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# to original state. Cache is just a means
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for key in self.__cache:
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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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"Reset attributes and change delegate."
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self.resetcache()
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self.delegate = delegate
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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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