114 lines
2.3 KiB
Python
114 lines
2.3 KiB
Python
# test __delattr__ and __setattr__
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# feature test for __setattr__/__delattr__
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try:
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class Test():
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def __delattr__(self, attr): pass
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del Test().noexist
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except AttributeError:
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print('SKIP')
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raise SystemExit
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# this class just prints the calls to see if they were executed
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class A():
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def __getattr__(self, attr):
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print('get', attr)
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return 1
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def __setattr__(self, attr, val):
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print('set', attr, val)
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def __delattr__(self, attr):
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print('del', attr)
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a = A()
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# check basic behaviour
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print(getattr(a, 'foo'))
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setattr(a, 'bar', 2)
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delattr(a, 'baz')
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# check meta behaviour
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getattr(a, '__getattr__') # should not call A.__getattr__
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getattr(a, '__setattr__') # should not call A.__getattr__
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getattr(a, '__delattr__') # should not call A.__getattr__
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setattr(a, '__setattr__', 1) # should call A.__setattr__
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delattr(a, '__delattr__') # should call A.__delattr__
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# this class acts like a dictionary
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class B:
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def __init__(self, d):
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# store the dict in the class, not instance, so
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# we don't get infinite recursion in __getattr_
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B.d = d
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def __getattr__(self, attr):
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if attr in B.d:
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return B.d[attr]
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else:
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raise AttributeError(attr)
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def __setattr__(self, attr, value):
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B.d[attr] = value
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def __delattr__(self, attr):
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del B.d[attr]
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a = B({"a":1, "b":2})
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print(a.a, a.b)
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a.a = 3
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print(a.a, a.b)
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del a.a
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try:
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print(a.a)
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except AttributeError:
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print("AttributeError")
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# test object.__setattr__
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class C:
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def __init__(self):
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pass
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def __setattr__(self, attr, value):
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print(attr, "=", value)
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def __delattr__(self, attr):
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print("del", attr)
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c = C()
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c.a = 5
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try:
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print(c.a)
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except AttributeError:
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print("AttributeError")
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object.__setattr__(c, "a", 5)
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super(C, c).__setattr__("b", 6)
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print(c.a)
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print(c.b)
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try:
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# attribute name must be string
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object.__setattr__(c, 5, 5)
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except TypeError:
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print("TypeError")
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# test object.__delattr__
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del c.a
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print(c.a)
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object.__delattr__(c, "a")
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try:
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print(c.a)
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except AttributeError:
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print("AttributeError")
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super(C, c).__delattr__("b")
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try:
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print(c.b)
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except AttributeError:
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print("AttributeError")
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try:
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object.__delattr__(c, "c")
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except AttributeError:
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print("AttributeError")
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