1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
import sys
import weakref
import python_weakref
def check(message, lhs, rhs):
if lhs != rhs:
raise RuntimeError(message, lhs, rhs)
callbacks = []
def callback(ref):
callbacks.append(ref)
ts = python_weakref.TestStruct()
# plain weak reference
ts_ref = weakref.ref(ts)
check("deref'd weakref is not object", ts_ref() is ts, True)
check("wrong number of weak references", weakref.getweakrefcount(ts), 1)
ts_ref().x = 123
# delete the weakref
del ts_ref
check("wrong number of weak references", weakref.getweakrefcount(ts), 0)
# create it again
ts_ref = weakref.ref(ts)
check("wrong number of weak references", weakref.getweakrefcount(ts), 1)
# weak reference proxy with callback
ts_ref_cb = weakref.proxy(ts, callback)
check("wrong number of weak references", weakref.getweakrefcount(ts), 2)
if sys.version_info >= (3,0):
# weakref proxy fails "is" but passes "=="
check("deref'd weakref != object", ts_ref_cb, ts)
check("weakref proxy not usable", ts_ref_cb.x, 123)
# delete object
check("callback was called", callbacks, [])
del ts
check("callback wasn't called", callbacks, [ts_ref_cb])
check("deref'd weakref is not None", ts_ref() is None, True)
|
