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