def test_change_type():
class A(object): pass
class B(object): pass
x = ref(A())
assert isinstance(x, A)
assert not isinstance(x, B)
assert issubclass(type(x), A)
assert not issubclass(type(x), B)
x << B()
assert isinstance(x, B)
assert not isinstance(x, A)
assert issubclass(type(x), B)
assert not issubclass(type(x), A)
def test_simple():
x = ref(1)
assert x == 1
assert (x << 2) == 2
assert x == 2
assert x + 1 == 3
assert x.__add__.__doc__ == int.__add__.__doc__
with overloading(False):
assert (x << 0) == 2
assert x == 2
y = ref_type(int)()
incr = lambda: y.__lshift__(1 + y)
incr()
assert y == 1
assert isinstance(x, int)
assert issubclass(type(x), int)