| import gc | |
| import sys | |
| import doctest | |
| import unittest | |
| import collections | |
| import weakref | |
| import operator | |
| import contextlib | |
| import copy | |
| import threading | |
| import time | |
| import random | |
| import textwrap | |
| from test import support | |
| from test.support import script_helper, ALWAYS_EQ | |
| from test.support import gc_collect | |
| from test.support import import_helper | |
| from test.support import threading_helper | |
| from test.support import is_wasi, Py_DEBUG | |
| # Used in ReferencesTestCase.test_ref_created_during_del() . | |
| ref_from_del = None | |
| # Used by FinalizeTestCase as a global that may be replaced by None | |
| # when the interpreter shuts down. | |
| _global_var = 'foobar' | |
| class C: | |
| def method(self): | |
| pass | |
| class Callable: | |
| bar = None | |
| def __call__(self, x): | |
| self.bar = x | |
| def create_function(): | |
| def f(): pass | |
| return f | |
| def create_bound_method(): | |
| return C().method | |
| class Object: | |
| def __init__(self, arg): | |
| self.arg = arg | |
| def __repr__(self): | |
| return "<Object %r>" % self.arg | |
| def __eq__(self, other): | |
| if isinstance(other, Object): | |
| return self.arg == other.arg | |
| return NotImplemented | |
| def __lt__(self, other): | |
| if isinstance(other, Object): | |
| return self.arg < other.arg | |
| return NotImplemented | |
| def __hash__(self): | |
| return hash(self.arg) | |
| def some_method(self): | |
| return 4 | |
| def other_method(self): | |
| return 5 | |
| class RefCycle: | |
| def __init__(self): | |
| self.cycle = self | |
| class TestBase(unittest.TestCase): | |
| def setUp(self): | |
| self.cbcalled = 0 | |
| def callback(self, ref): | |
| self.cbcalled += 1 | |
| @contextlib.contextmanager | |
| def collect_in_thread(period=0.005): | |
| """ | |
| Ensure GC collections happen in a different thread, at a high frequency. | |
| """ | |
| please_stop = False | |
| def collect(): | |
| while not please_stop: | |
| time.sleep(period) | |
| gc.collect() | |
| with support.disable_gc(): | |
| t = threading.Thread(target=collect) | |
| t.start() | |
| try: | |
| yield | |
| finally: | |
| please_stop = True | |
| t.join() | |
| class ReferencesTestCase(TestBase): | |
| def test_basic_ref(self): | |
| self.check_basic_ref(C) | |
| self.check_basic_ref(create_function) | |
| self.check_basic_ref(create_bound_method) | |
| # Just make sure the tp_repr handler doesn't raise an exception. | |
| # Live reference: | |
| o = C() | |
| wr = weakref.ref(o) | |
| repr(wr) | |
| # Dead reference: | |
| del o | |
| repr(wr) | |
| @support.cpython_only | |
| def test_ref_repr(self): | |
| obj = C() | |
| ref = weakref.ref(obj) | |
| regex = ( | |
| rf"<weakref at 0x[0-9a-fA-F]+; " | |
| rf"to '{'' if __name__ == '__main__' else C.__module__ + '.'}{C.__qualname__}' " | |
| rf"at 0x[0-9a-fA-F]+>" | |
| ) | |
| self.assertRegex(repr(ref), regex) | |
| obj = None | |
| gc_collect() | |
| self.assertRegex(repr(ref), | |
| rf'<weakref at 0x[0-9a-fA-F]+; dead>') | |
| # test type with __name__ | |
| class WithName: | |
| @property | |
| def __name__(self): | |
| return "custom_name" | |
| obj2 = WithName() | |
| ref2 = weakref.ref(obj2) | |
| regex = ( | |
| rf"<weakref at 0x[0-9a-fA-F]+; " | |
| rf"to '{'' if __name__ == '__main__' else WithName.__module__ + '.'}" | |
| rf"{WithName.__qualname__}' " | |
| rf"at 0x[0-9a-fA-F]+ +\(custom_name\)>" | |
| ) | |
| self.assertRegex(repr(ref2), regex) | |
| def test_repr_failure_gh99184(self): | |
| class MyConfig(dict): | |
| def __getattr__(self, x): | |
| return self[x] | |
| obj = MyConfig(offset=5) | |
| obj_weakref = weakref.ref(obj) | |
| self.assertIn('MyConfig', repr(obj_weakref)) | |
| self.assertIn('MyConfig', str(obj_weakref)) | |
| def test_repr_name_lookup_error(self): | |
| # An error raised while looking up __name__ propagates. | |
| class BadName: | |
| @property | |
| def __name__(self): | |
| raise ZeroDivisionError | |
| obj = BadName() | |
| with self.assertRaises(ZeroDivisionError): | |
| repr(weakref.ref(obj)) | |
| def test_basic_callback(self): | |
| self.check_basic_callback(C) | |
| self.check_basic_callback(create_function) | |
| self.check_basic_callback(create_bound_method) | |
| def test_non_callable_callback(self): | |
| c = C() | |
| self.assertRaises(TypeError, weakref.ref, c, 42) | |
| self.assertRaises(TypeError, weakref.proxy, c, 42) | |
| @support.cpython_only | |
| def test_cfunction(self): | |
| _testcapi = import_helper.import_module("_testcapi") | |
| create_cfunction = _testcapi.create_cfunction | |
| f = create_cfunction() | |
| wr = weakref.ref(f) | |
| self.assertIs(wr(), f) | |
| del f | |
| self.assertIsNone(wr()) | |
| self.check_basic_ref(create_cfunction) | |
| self.check_basic_callback(create_cfunction) | |
| def test_multiple_callbacks(self): | |
| o = C() | |
| ref1 = weakref.ref(o, self.callback) | |
| ref2 = weakref.ref(o, self.callback) | |
| del o | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertIsNone(ref1(), "expected reference to be invalidated") | |
| self.assertIsNone(ref2(), "expected reference to be invalidated") | |
| self.assertEqual(self.cbcalled, 2, | |
| "callback not called the right number of times") | |
| def test_multiple_selfref_callbacks(self): | |
| # Make sure all references are invalidated before callbacks are called | |
| # | |
| # What's important here is that we're using the first | |
| # reference in the callback invoked on the second reference | |
| # (the most recently created ref is cleaned up first). This | |
| # tests that all references to the object are invalidated | |
| # before any of the callbacks are invoked, so that we only | |
| # have one invocation of _weakref.c:cleanup_helper() active | |
| # for a particular object at a time. | |
| # | |
| def callback(object, self=self): | |
| self.ref() | |
| c = C() | |
| self.ref = weakref.ref(c, callback) | |
| ref1 = weakref.ref(c, callback) | |
| del c | |
| def test_constructor_kwargs(self): | |
| c = C() | |
| self.assertRaises(TypeError, weakref.ref, c, callback=None) | |
| def test_proxy_ref(self): | |
| o = C() | |
| o.bar = 1 | |
| ref1 = weakref.proxy(o, self.callback) | |
| ref2 = weakref.proxy(o, self.callback) | |
| del o | |
| gc_collect() # For PyPy or other GCs. | |
| def check(proxy): | |
| proxy.bar | |
| self.assertRaises(ReferenceError, check, ref1) | |
| self.assertRaises(ReferenceError, check, ref2) | |
| ref3 = weakref.proxy(C()) | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertRaises(ReferenceError, bool, ref3) | |
| self.assertEqual(self.cbcalled, 2) | |
| @support.cpython_only | |
| def test_proxy_repr(self): | |
| obj = C() | |
| ref = weakref.proxy(obj, self.callback) | |
| regex = ( | |
| rf"<weakproxy at 0x[0-9a-fA-F]+; " | |
| rf"to '{'' if __name__ == '__main__' else C.__module__ + '.'}{C.__qualname__}' " | |
| rf"at 0x[0-9a-fA-F]+>" | |
| ) | |
| self.assertRegex(repr(ref), regex) | |
| obj = None | |
| gc_collect() | |
| self.assertRegex(repr(ref), | |
| rf'<weakproxy at 0x[0-9a-fA-F]+; dead>') | |
| def check_basic_ref(self, factory): | |
| o = factory() | |
| ref = weakref.ref(o) | |
| self.assertIsNotNone(ref(), | |
| "weak reference to live object should be live") | |
| o2 = ref() | |
| self.assertIs(o, o2, | |
| "<ref>() should return original object if live") | |
| def check_basic_callback(self, factory): | |
| self.cbcalled = 0 | |
| o = factory() | |
| ref = weakref.ref(o, self.callback) | |
| del o | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(self.cbcalled, 1, | |
| "callback did not properly set 'cbcalled'") | |
| self.assertIsNone(ref(), | |
| "ref2 should be dead after deleting object reference") | |
| def test_ref_reuse(self): | |
| o = C() | |
| ref1 = weakref.ref(o) | |
| # create a proxy to make sure that there's an intervening creation | |
| # between these two; it should make no difference | |
| proxy = weakref.proxy(o) | |
| ref2 = weakref.ref(o) | |
| self.assertIs(ref1, ref2, | |
| "reference object w/out callback should be re-used") | |
| o = C() | |
| proxy = weakref.proxy(o) | |
| ref1 = weakref.ref(o) | |
| ref2 = weakref.ref(o) | |
| self.assertIs(ref1, ref2, | |
| "reference object w/out callback should be re-used") | |
| self.assertEqual(weakref.getweakrefcount(o), 2, | |
| "wrong weak ref count for object") | |
| del proxy | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(weakref.getweakrefcount(o), 1, | |
| "wrong weak ref count for object after deleting proxy") | |
| def test_proxy_reuse(self): | |
| o = C() | |
| proxy1 = weakref.proxy(o) | |
| ref = weakref.ref(o) | |
| proxy2 = weakref.proxy(o) | |
| self.assertIs(proxy1, proxy2, | |
| "proxy object w/out callback should have been re-used") | |
| def test_basic_proxy(self): | |
| o = C() | |
| self.check_proxy(o, weakref.proxy(o)) | |
| L = collections.UserList() | |
| p = weakref.proxy(L) | |
| self.assertFalse(p, "proxy for empty UserList should be false") | |
| p.append(12) | |
| self.assertEqual(len(L), 1) | |
| self.assertTrue(p, "proxy for non-empty UserList should be true") | |
| p[:] = [2, 3] | |
| self.assertEqual(len(L), 2) | |
| self.assertEqual(len(p), 2) | |
| self.assertIn(3, p, "proxy didn't support __contains__() properly") | |
| p[1] = 5 | |
| self.assertEqual(L[1], 5) | |
| self.assertEqual(p[1], 5) | |
| L2 = collections.UserList(L) | |
| p2 = weakref.proxy(L2) | |
| self.assertEqual(p, p2) | |
| ## self.assertEqual(repr(L2), repr(p2)) | |
| L3 = collections.UserList(range(10)) | |
| p3 = weakref.proxy(L3) | |
| self.assertEqual(L3[:], p3[:]) | |
| self.assertEqual(L3[5:], p3[5:]) | |
| self.assertEqual(L3[:5], p3[:5]) | |
| self.assertEqual(L3[2:5], p3[2:5]) | |
| def test_proxy_unicode(self): | |
| # See bug 5037 | |
| class C(object): | |
| def __str__(self): | |
| return "string" | |
| def __bytes__(self): | |
| return b"bytes" | |
| instance = C() | |
| self.assertIn("__bytes__", dir(weakref.proxy(instance))) | |
| self.assertEqual(bytes(weakref.proxy(instance)), b"bytes") | |
| def test_proxy_index(self): | |
| class C: | |
| def __index__(self): | |
| return 10 | |
| o = C() | |
| p = weakref.proxy(o) | |
| self.assertEqual(operator.index(p), 10) | |
| def test_proxy_div(self): | |
| class C: | |
| def __floordiv__(self, other): | |
| return 42 | |
| def __ifloordiv__(self, other): | |
| return 21 | |
| o = C() | |
| p = weakref.proxy(o) | |
| self.assertEqual(p // 5, 42) | |
| p //= 5 | |
| self.assertEqual(p, 21) | |
| def test_proxy_matmul(self): | |
| class C: | |
| def __matmul__(self, other): | |
| return 1729 | |
| def __rmatmul__(self, other): | |
| return -163 | |
| def __imatmul__(self, other): | |
| return 561 | |
| o = C() | |
| p = weakref.proxy(o) | |
| self.assertEqual(p @ 5, 1729) | |
| self.assertEqual(5 @ p, -163) | |
| p @= 5 | |
| self.assertEqual(p, 561) | |
| # The PyWeakref_* C API is documented as allowing either NULL or | |
| # None as the value for the callback, where either means "no | |
| # callback". The "no callback" ref and proxy objects are supposed | |
| # to be shared so long as they exist by all callers so long as | |
| # they are active. In Python 2.3.3 and earlier, this guarantee | |
| # was not honored, and was broken in different ways for | |
| # PyWeakref_NewRef() and PyWeakref_NewProxy(). (Two tests.) | |
| def test_shared_ref_without_callback(self): | |
| self.check_shared_without_callback(weakref.ref) | |
| def test_shared_proxy_without_callback(self): | |
| self.check_shared_without_callback(weakref.proxy) | |
| def check_shared_without_callback(self, makeref): | |
| o = Object(1) | |
| p1 = makeref(o, None) | |
| p2 = makeref(o, None) | |
| self.assertIs(p1, p2, "both callbacks were None in the C API") | |
| del p1, p2 | |
| p1 = makeref(o) | |
| p2 = makeref(o, None) | |
| self.assertIs(p1, p2, "callbacks were NULL, None in the C API") | |
| del p1, p2 | |
| p1 = makeref(o) | |
| p2 = makeref(o) | |
| self.assertIs(p1, p2, "both callbacks were NULL in the C API") | |
| del p1, p2 | |
| p1 = makeref(o, None) | |
| p2 = makeref(o) | |
| self.assertIs(p1, p2, "callbacks were None, NULL in the C API") | |
| def test_callable_proxy(self): | |
| o = Callable() | |
| ref1 = weakref.proxy(o) | |
| self.check_proxy(o, ref1) | |
| self.assertIs(type(ref1), weakref.CallableProxyType, | |
| "proxy is not of callable type") | |
| ref1('twinkies!') | |
| self.assertEqual(o.bar, 'twinkies!', | |
| "call through proxy not passed through to original") | |
| ref1(x='Splat.') | |
| self.assertEqual(o.bar, 'Splat.', | |
| "call through proxy not passed through to original") | |
| # expect due to too few args | |
| self.assertRaises(TypeError, ref1) | |
| # expect due to too many args | |
| self.assertRaises(TypeError, ref1, 1, 2, 3) | |
| def check_proxy(self, o, proxy): | |
| o.foo = 1 | |
| self.assertEqual(proxy.foo, 1, | |
| "proxy does not reflect attribute addition") | |
| o.foo = 2 | |
| self.assertEqual(proxy.foo, 2, | |
| "proxy does not reflect attribute modification") | |
| del o.foo | |
| self.assertNotHasAttr(proxy, 'foo', | |
| "proxy does not reflect attribute removal") | |
| proxy.foo = 1 | |
| self.assertEqual(o.foo, 1, | |
| "object does not reflect attribute addition via proxy") | |
| proxy.foo = 2 | |
| self.assertEqual(o.foo, 2, | |
| "object does not reflect attribute modification via proxy") | |
| del proxy.foo | |
| self.assertNotHasAttr(o, 'foo', | |
| "object does not reflect attribute removal via proxy") | |
| def test_proxy_deletion(self): | |
| # Test clearing of SF bug #762891 | |
| class Foo: | |
| result = None | |
| def __delitem__(self, accessor): | |
| self.result = accessor | |
| g = Foo() | |
| f = weakref.proxy(g) | |
| del f[0] | |
| self.assertEqual(f.result, 0) | |
| def test_proxy_bool(self): | |
| # Test clearing of SF bug #1170766 | |
| class List(list): pass | |
| lyst = List() | |
| self.assertEqual(bool(weakref.proxy(lyst)), bool(lyst)) | |
| def test_proxy_iter(self): | |
| # Test fails with a debug build of the interpreter | |
| # (see bpo-38395). | |
| obj = None | |
| class MyObj: | |
| def __iter__(self): | |
| nonlocal obj | |
| del obj | |
| return NotImplemented | |
| obj = MyObj() | |
| p = weakref.proxy(obj) | |
| with self.assertRaises(TypeError): | |
| # "blech" in p calls MyObj.__iter__ through the proxy, | |
| # without keeping a reference to the real object, so it | |
| # can be killed in the middle of the call | |
| "blech" in p | |
| def test_proxy_next(self): | |
| arr = [4, 5, 6] | |
| def iterator_func(): | |
| yield from arr | |
| it = iterator_func() | |
| class IteratesWeakly: | |
| def __iter__(self): | |
| return weakref.proxy(it) | |
| weak_it = IteratesWeakly() | |
| # Calls proxy.__next__ | |
| self.assertEqual(list(weak_it), [4, 5, 6]) | |
| def test_proxy_bad_next(self): | |
| # bpo-44720: PyIter_Next() shouldn't be called if the reference | |
| # isn't an iterator. | |
| not_an_iterator = lambda: 0 | |
| class A: | |
| def __iter__(self): | |
| return weakref.proxy(not_an_iterator) | |
| a = A() | |
| msg = "Weakref proxy referenced a non-iterator" | |
| with self.assertRaisesRegex(TypeError, msg): | |
| list(a) | |
| def test_proxy_reversed(self): | |
| class MyObj: | |
| def __len__(self): | |
| return 3 | |
| def __reversed__(self): | |
| return iter('cba') | |
| obj = MyObj() | |
| self.assertEqual("".join(reversed(weakref.proxy(obj))), "cba") | |
| def test_proxy_hash(self): | |
| class MyObj: | |
| def __hash__(self): | |
| return 42 | |
| obj = MyObj() | |
| with self.assertRaises(TypeError): | |
| hash(weakref.proxy(obj)) | |
| class MyObj: | |
| __hash__ = None | |
| obj = MyObj() | |
| with self.assertRaises(TypeError): | |
| hash(weakref.proxy(obj)) | |
| def test_getweakrefcount(self): | |
| o = C() | |
| ref1 = weakref.ref(o) | |
| ref2 = weakref.ref(o, self.callback) | |
| self.assertEqual(weakref.getweakrefcount(o), 2, | |
| "got wrong number of weak reference objects") | |
| proxy1 = weakref.proxy(o) | |
| proxy2 = weakref.proxy(o, self.callback) | |
| self.assertEqual(weakref.getweakrefcount(o), 4, | |
| "got wrong number of weak reference objects") | |
| del ref1, ref2, proxy1, proxy2 | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(weakref.getweakrefcount(o), 0, | |
| "weak reference objects not unlinked from" | |
| " referent when discarded.") | |
| # assumes ints do not support weakrefs | |
| self.assertEqual(weakref.getweakrefcount(1), 0, | |
| "got wrong number of weak reference objects for int") | |
| def test_getweakrefs(self): | |
| o = C() | |
| ref1 = weakref.ref(o, self.callback) | |
| ref2 = weakref.ref(o, self.callback) | |
| del ref1 | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(weakref.getweakrefs(o), [ref2], | |
| "list of refs does not match") | |
| o = C() | |
| ref1 = weakref.ref(o, self.callback) | |
| ref2 = weakref.ref(o, self.callback) | |
| del ref2 | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(weakref.getweakrefs(o), [ref1], | |
| "list of refs does not match") | |
| del ref1 | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(weakref.getweakrefs(o), [], | |
| "list of refs not cleared") | |
| # assumes ints do not support weakrefs | |
| self.assertEqual(weakref.getweakrefs(1), [], | |
| "list of refs does not match for int") | |
| def test_newstyle_number_ops(self): | |
| class F(float): | |
| pass | |
| f = F(2.0) | |
| p = weakref.proxy(f) | |
| self.assertEqual(p + 1.0, 3.0) | |
| self.assertEqual(1.0 + p, 3.0) # this used to SEGV | |
| def test_callbacks_protected(self): | |
| # Callbacks protected from already-set exceptions? | |
| # Regression test for SF bug #478534. | |
| class BogusError(Exception): | |
| pass | |
| data = {} | |
| def remove(k): | |
| del data[k] | |
| def encapsulate(): | |
| f = lambda : () | |
| data[weakref.ref(f, remove)] = None | |
| raise BogusError | |
| try: | |
| encapsulate() | |
| except BogusError: | |
| pass | |
| else: | |
| self.fail("exception not properly restored") | |
| try: | |
| encapsulate() | |
| except BogusError: | |
| pass | |
| else: | |
| self.fail("exception not properly restored") | |
| def test_sf_bug_840829(self): | |
| # "weakref callbacks and gc corrupt memory" | |
| # subtype_dealloc erroneously exposed a new-style instance | |
| # already in the process of getting deallocated to gc, | |
| # causing double-deallocation if the instance had a weakref | |
| # callback that triggered gc. | |
| # If the bug exists, there probably won't be an obvious symptom | |
| # in a release build. In a debug build, a segfault will occur | |
| # when the second attempt to remove the instance from the "list | |
| # of all objects" occurs. | |
| import gc | |
| class C(object): | |
| pass | |
| c = C() | |
| wr = weakref.ref(c, lambda ignore: gc.collect()) | |
| del c | |
| # There endeth the first part. It gets worse. | |
| del wr | |
| c1 = C() | |
| c1.i = C() | |
| wr = weakref.ref(c1.i, lambda ignore: gc.collect()) | |
| c2 = C() | |
| c2.c1 = c1 | |
| del c1 # still alive because c2 points to it | |
| # Now when subtype_dealloc gets called on c2, it's not enough just | |
| # that c2 is immune from gc while the weakref callbacks associated | |
| # with c2 execute (there are none in this 2nd half of the test, btw). | |
| # subtype_dealloc goes on to call the base classes' deallocs too, | |
| # so any gc triggered by weakref callbacks associated with anything | |
| # torn down by a base class dealloc can also trigger double | |
| # deallocation of c2. | |
| del c2 | |
| def test_callback_in_cycle(self): | |
| import gc | |
| class J(object): | |
| pass | |
| class II(object): | |
| def acallback(self, ignore): | |
| self.J | |
| I = II() | |
| I.J = J | |
| I.wr = weakref.ref(J, I.acallback) | |
| # Now J and II are each in a self-cycle (as all new-style class | |
| # objects are, since their __mro__ points back to them). I holds | |
| # both a weak reference (I.wr) and a strong reference (I.J) to class | |
| # J. I is also in a cycle (I.wr points to a weakref that references | |
| # I.acallback). When we del these three, they all become trash, but | |
| # the cycles prevent any of them from getting cleaned up immediately. | |
| # Instead they have to wait for cyclic gc to deduce that they're | |
| # trash. | |
| # | |
| # gc used to call tp_clear on all of them, and the order in which | |
| # it does that is pretty accidental. The exact order in which we | |
| # built up these things manages to provoke gc into running tp_clear | |
| # in just the right order (I last). Calling tp_clear on II leaves | |
| # behind an insane class object (its __mro__ becomes NULL). Calling | |
| # tp_clear on J breaks its self-cycle, but J doesn't get deleted | |
| # just then because of the strong reference from I.J. Calling | |
| # tp_clear on I starts to clear I's __dict__, and just happens to | |
| # clear I.J first -- I.wr is still intact. That removes the last | |
| # reference to J, which triggers the weakref callback. The callback | |
| # tries to do "self.J", and instances of new-style classes look up | |
| # attributes ("J") in the class dict first. The class (II) wants to | |
| # search II.__mro__, but that's NULL. The result was a segfault in | |
| # a release build, and an assert failure in a debug build. | |
| del I, J, II | |
| gc.collect() | |
| def test_callback_reachable_one_way(self): | |
| import gc | |
| # This one broke the first patch that fixed the previous test. In this case, | |
| # the objects reachable from the callback aren't also reachable | |
| # from the object (c1) *triggering* the callback: you can get to | |
| # c1 from c2, but not vice-versa. The result was that c2's __dict__ | |
| # got tp_clear'ed by the time the c2.cb callback got invoked. | |
| class C: | |
| def cb(self, ignore): | |
| self.me | |
| self.c1 | |
| self.wr | |
| c1, c2 = C(), C() | |
| c2.me = c2 | |
| c2.c1 = c1 | |
| c2.wr = weakref.ref(c1, c2.cb) | |
| del c1, c2 | |
| gc.collect() | |
| def test_callback_different_classes(self): | |
| import gc | |
| # Like test_callback_reachable_one_way, except c2 and c1 have different | |
| # classes. c2's class (C) isn't reachable from c1 then, so protecting | |
| # objects reachable from the dying object (c1) isn't enough to stop | |
| # c2's class (C) from getting tp_clear'ed before c2.cb is invoked. | |
| # The result was a segfault (C.__mro__ was NULL when the callback | |
| # tried to look up self.me). | |
| class C(object): | |
| def cb(self, ignore): | |
| self.me | |
| self.c1 | |
| self.wr | |
| class D: | |
| pass | |
| c1, c2 = D(), C() | |
| c2.me = c2 | |
| c2.c1 = c1 | |
| c2.wr = weakref.ref(c1, c2.cb) | |
| del c1, c2, C, D | |
| gc.collect() | |
| def test_callback_in_cycle_resurrection(self): | |
| import gc | |
| # Do something nasty in a weakref callback: resurrect objects | |
| # from dead cycles. For this to be attempted, the weakref and | |
| # its callback must also be part of the cyclic trash (else the | |
| # objects reachable via the callback couldn't be in cyclic trash | |
| # to begin with -- the callback would act like an external root). | |
| # But gc clears trash weakrefs with callbacks early now, which | |
| # disables the callbacks, so the callbacks shouldn't get called | |
| # at all (and so nothing actually gets resurrected). | |
| alist = [] | |
| class C(object): | |
| def __init__(self, value): | |
| self.attribute = value | |
| def acallback(self, ignore): | |
| alist.append(self.c) | |
| c1, c2 = C(1), C(2) | |
| c1.c = c2 | |
| c2.c = c1 | |
| c1.wr = weakref.ref(c2, c1.acallback) | |
| c2.wr = weakref.ref(c1, c2.acallback) | |
| def C_went_away(ignore): | |
| alist.append("C went away") | |
| wr = weakref.ref(C, C_went_away) | |
| del c1, c2, C # make them all trash | |
| self.assertEqual(alist, []) # del isn't enough to reclaim anything | |
| gc.collect() | |
| # c1.wr and c2.wr were part of the cyclic trash, so should have | |
| # been cleared without their callbacks executing. OTOH, the weakref | |
| # to C is bound to a function local (wr), and wasn't trash, so that | |
| # callback should have been invoked when C went away. | |
| self.assertEqual(alist, ["C went away"]) | |
| # The remaining weakref should be dead now (its callback ran). | |
| self.assertEqual(wr(), None) | |
| del alist[:] | |
| gc.collect() | |
| self.assertEqual(alist, []) | |
| def test_callbacks_on_callback(self): | |
| import gc | |
| # Set up weakref callbacks *on* weakref callbacks. | |
| alist = [] | |
| def safe_callback(ignore): | |
| alist.append("safe_callback called") | |
| class C(object): | |
| def cb(self, ignore): | |
| alist.append("cb called") | |
| c, d = C(), C() | |
| c.other = d | |
| d.other = c | |
| callback = c.cb | |
| c.wr = weakref.ref(d, callback) # this won't trigger | |
| d.wr = weakref.ref(callback, d.cb) # ditto | |
| external_wr = weakref.ref(callback, safe_callback) # but this will | |
| self.assertIs(external_wr(), callback) | |
| # The weakrefs attached to c and d should get cleared, so that | |
| # C.cb is never called. But external_wr isn't part of the cyclic | |
| # trash, and no cyclic trash is reachable from it, so safe_callback | |
| # should get invoked when the bound method object callback (c.cb) | |
| # -- which is itself a callback, and also part of the cyclic trash -- | |
| # gets reclaimed at the end of gc. | |
| del callback, c, d, C | |
| self.assertEqual(alist, []) # del isn't enough to clean up cycles | |
| gc.collect() | |
| self.assertEqual(alist, ["safe_callback called"]) | |
| self.assertEqual(external_wr(), None) | |
| del alist[:] | |
| gc.collect() | |
| self.assertEqual(alist, []) | |
| def test_gc_during_ref_creation(self): | |
| self.check_gc_during_creation(weakref.ref) | |
| def test_gc_during_proxy_creation(self): | |
| self.check_gc_during_creation(weakref.proxy) | |
| def check_gc_during_creation(self, makeref): | |
| thresholds = gc.get_threshold() | |
| gc.set_threshold(1, 1, 1) | |
| gc.collect() | |
| class A: | |
| pass | |
| def callback(*args): | |
| pass | |
| referenced = A() | |
| a = A() | |
| a.a = a | |
| a.wr = makeref(referenced) | |
| try: | |
| # now make sure the object and the ref get labeled as | |
| # cyclic trash: | |
| a = A() | |
| weakref.ref(referenced, callback) | |
| finally: | |
| gc.set_threshold(*thresholds) | |
| def test_ref_created_during_del(self): | |
| # Bug #1377858 | |
| # A weakref created in an object's __del__() would crash the | |
| # interpreter when the weakref was cleaned up since it would refer to | |
| # non-existent memory. This test should not segfault the interpreter. | |
| class Target(object): | |
| def __del__(self): | |
| global ref_from_del | |
| ref_from_del = weakref.ref(self) | |
| w = Target() | |
| def test_init(self): | |
| # Issue 3634 | |
| # <weakref to class>.__init__() doesn't check errors correctly | |
| r = weakref.ref(Exception) | |
| self.assertRaises(TypeError, r.__init__, 0, 0, 0, 0, 0) | |
| # No exception should be raised here | |
| gc.collect() | |
| def test_classes(self): | |
| # Check that classes are weakrefable. | |
| class A(object): | |
| pass | |
| l = [] | |
| weakref.ref(int) | |
| a = weakref.ref(A, l.append) | |
| A = None | |
| gc.collect() | |
| self.assertEqual(a(), None) | |
| self.assertEqual(l, [a]) | |
| def test_equality(self): | |
| # Alive weakrefs defer equality testing to their underlying object. | |
| x = Object(1) | |
| y = Object(1) | |
| z = Object(2) | |
| a = weakref.ref(x) | |
| b = weakref.ref(y) | |
| c = weakref.ref(z) | |
| d = weakref.ref(x) | |
| # Note how we directly test the operators here, to stress both | |
| # __eq__ and __ne__. | |
| self.assertTrue(a == b) | |
| self.assertFalse(a != b) | |
| self.assertFalse(a == c) | |
| self.assertTrue(a != c) | |
| self.assertTrue(a == d) | |
| self.assertFalse(a != d) | |
| self.assertFalse(a == x) | |
| self.assertTrue(a != x) | |
| self.assertTrue(a == ALWAYS_EQ) | |
| self.assertFalse(a != ALWAYS_EQ) | |
| del x, y, z | |
| gc.collect() | |
| for r in a, b, c: | |
| # Sanity check | |
| self.assertIs(r(), None) | |
| # Dead weakrefs compare by identity: whether `a` and `d` are the | |
| # same weakref object is an implementation detail, since they pointed | |
| # to the same original object and didn't have a callback. | |
| # (see issue #16453). | |
| self.assertFalse(a == b) | |
| self.assertTrue(a != b) | |
| self.assertFalse(a == c) | |
| self.assertTrue(a != c) | |
| self.assertEqual(a == d, a is d) | |
| self.assertEqual(a != d, a is not d) | |
| def test_ordering(self): | |
| # weakrefs cannot be ordered, even if the underlying objects can. | |
| ops = [operator.lt, operator.gt, operator.le, operator.ge] | |
| x = Object(1) | |
| y = Object(1) | |
| a = weakref.ref(x) | |
| b = weakref.ref(y) | |
| for op in ops: | |
| self.assertRaises(TypeError, op, a, b) | |
| # Same when dead. | |
| del x, y | |
| gc.collect() | |
| for op in ops: | |
| self.assertRaises(TypeError, op, a, b) | |
| def test_hashing(self): | |
| # Alive weakrefs hash the same as the underlying object | |
| x = Object(42) | |
| y = Object(42) | |
| a = weakref.ref(x) | |
| b = weakref.ref(y) | |
| self.assertEqual(hash(a), hash(42)) | |
| del x, y | |
| gc.collect() | |
| # Dead weakrefs: | |
| # - retain their hash is they were hashed when alive; | |
| # - otherwise, cannot be hashed. | |
| self.assertEqual(hash(a), hash(42)) | |
| self.assertRaises(TypeError, hash, b) | |
| @unittest.skipIf(is_wasi and Py_DEBUG, "requires deep stack") | |
| def test_trashcan_16602(self): | |
| # Issue #16602: when a weakref's target was part of a long | |
| # deallocation chain, the trashcan mechanism could delay clearing | |
| # of the weakref and make the target object visible from outside | |
| # code even though its refcount had dropped to 0. A crash ensued. | |
| class C: | |
| def __init__(self, parent): | |
| if not parent: | |
| return | |
| wself = weakref.ref(self) | |
| def cb(wparent): | |
| o = wself() | |
| self.wparent = weakref.ref(parent, cb) | |
| d = weakref.WeakKeyDictionary() | |
| root = c = C(None) | |
| for n in range(100): | |
| d[c] = c = C(c) | |
| del root | |
| gc.collect() | |
| def test_callback_attribute(self): | |
| x = Object(1) | |
| callback = lambda ref: None | |
| ref1 = weakref.ref(x, callback) | |
| self.assertIs(ref1.__callback__, callback) | |
| ref2 = weakref.ref(x) | |
| self.assertIsNone(ref2.__callback__) | |
| def test_callback_attribute_after_deletion(self): | |
| x = Object(1) | |
| ref = weakref.ref(x, self.callback) | |
| self.assertIsNotNone(ref.__callback__) | |
| del x | |
| support.gc_collect() | |
| self.assertIsNone(ref.__callback__) | |
| def test_set_callback_attribute(self): | |
| x = Object(1) | |
| callback = lambda ref: None | |
| ref1 = weakref.ref(x, callback) | |
| with self.assertRaises(AttributeError): | |
| ref1.__callback__ = lambda ref: None | |
| def test_callback_gcs(self): | |
| class ObjectWithDel(Object): | |
| def __del__(self): pass | |
| x = ObjectWithDel(1) | |
| ref1 = weakref.ref(x, lambda ref: support.gc_collect()) | |
| del x | |
| support.gc_collect() | |
| @support.nomemtest | |
| def test_no_memory_when_clearing(self): | |
| # gh-118331: Make sure we do not raise an exception from the destructor | |
| # when clearing weakrefs if allocating the intermediate tuple fails. | |
| code = textwrap.dedent(""" | |
| import weakref | |
| from test import support | |
| class TestObj: | |
| pass | |
| def callback(obj): | |
| pass | |
| obj = TestObj() | |
| # The choice of 50 is arbitrary, but must be large enough to ensure | |
| # the allocation won't be serviced by the free list. | |
| wrs = [weakref.ref(obj, callback) for _ in range(50)] | |
| support.inject_memory_error() | |
| del obj | |
| """).strip() | |
| res, _ = script_helper.run_python_until_end("-c", code) | |
| stderr = res.err.decode("ascii", "backslashreplace") | |
| self.assertNotRegex(stderr, "_Py_Dealloc: Deallocator of type 'TestObj'") | |
| def test_clearing_weakrefs_in_gc(self): | |
| # This test checks that when finalizers are called: | |
| # 1. weakrefs with callbacks have been cleared | |
| # 2. weakrefs without callbacks have not been cleared | |
| errors = [] | |
| def test(): | |
| class Class: | |
| def __init__(self): | |
| self._self = self | |
| self.wr1 = weakref.ref(Class, lambda x: None) | |
| self.wr2 = weakref.ref(Class) | |
| def __del__(self): | |
| # we can't use assert* here, because gc will swallow | |
| # exceptions | |
| if self.wr1() is not None: | |
| errors.append("weakref with callback as cleared") | |
| if self.wr2() is not Class: | |
| errors.append("weakref without callback was cleared") | |
| Class() | |
| test() | |
| gc.collect() | |
| self.assertEqual(errors, []) | |
| class SubclassableWeakrefTestCase(TestBase): | |
| def test_subclass_refs(self): | |
| class MyRef(weakref.ref): | |
| def __init__(self, ob, callback=None, value=42): | |
| self.value = value | |
| super().__init__(ob, callback) | |
| def __call__(self): | |
| self.called = True | |
| return super().__call__() | |
| o = Object("foo") | |
| mr = MyRef(o, value=24) | |
| self.assertIs(mr(), o) | |
| self.assertTrue(mr.called) | |
| self.assertEqual(mr.value, 24) | |
| del o | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertIsNone(mr()) | |
| self.assertTrue(mr.called) | |
| def test_subclass_refs_dont_replace_standard_refs(self): | |
| class MyRef(weakref.ref): | |
| pass | |
| o = Object(42) | |
| r1 = MyRef(o) | |
| r2 = weakref.ref(o) | |
| self.assertIsNot(r1, r2) | |
| self.assertEqual(weakref.getweakrefs(o), [r2, r1]) | |
| self.assertEqual(weakref.getweakrefcount(o), 2) | |
| r3 = MyRef(o) | |
| self.assertEqual(weakref.getweakrefcount(o), 3) | |
| refs = weakref.getweakrefs(o) | |
| self.assertEqual(len(refs), 3) | |
| self.assertIs(r2, refs[0]) | |
| self.assertIn(r1, refs[1:]) | |
| self.assertIn(r3, refs[1:]) | |
| def test_subclass_refs_dont_conflate_callbacks(self): | |
| class MyRef(weakref.ref): | |
| pass | |
| o = Object(42) | |
| r1 = MyRef(o, id) | |
| r2 = MyRef(o, str) | |
| self.assertIsNot(r1, r2) | |
| refs = weakref.getweakrefs(o) | |
| self.assertIn(r1, refs) | |
| self.assertIn(r2, refs) | |
| def test_subclass_refs_with_slots(self): | |
| class MyRef(weakref.ref): | |
| __slots__ = "slot1", "slot2" | |
| def __new__(type, ob, callback, slot1, slot2): | |
| return weakref.ref.__new__(type, ob, callback) | |
| def __init__(self, ob, callback, slot1, slot2): | |
| self.slot1 = slot1 | |
| self.slot2 = slot2 | |
| def meth(self): | |
| return self.slot1 + self.slot2 | |
| o = Object(42) | |
| r = MyRef(o, None, "abc", "def") | |
| self.assertEqual(r.slot1, "abc") | |
| self.assertEqual(r.slot2, "def") | |
| self.assertEqual(r.meth(), "abcdef") | |
| self.assertNotHasAttr(r, "__dict__") | |
| def test_subclass_refs_with_cycle(self): | |
| """Confirm https://bugs.python.org/issue3100 is fixed.""" | |
| # An instance of a weakref subclass can have attributes. | |
| # If such a weakref holds the only strong reference to the object, | |
| # deleting the weakref will delete the object. In this case, | |
| # the callback must not be called, because the ref object is | |
| # being deleted. | |
| class MyRef(weakref.ref): | |
| pass | |
| # Use a local callback, for "regrtest -R::" | |
| # to detect refcounting problems | |
| def callback(w): | |
| self.cbcalled += 1 | |
| o = C() | |
| r1 = MyRef(o, callback) | |
| r1.o = o | |
| del o | |
| del r1 # Used to crash here | |
| self.assertEqual(self.cbcalled, 0) | |
| # Same test, with two weakrefs to the same object | |
| # (since code paths are different) | |
| o = C() | |
| r1 = MyRef(o, callback) | |
| r2 = MyRef(o, callback) | |
| r1.r = r2 | |
| r2.o = o | |
| del o | |
| del r2 | |
| del r1 # Used to crash here | |
| self.assertEqual(self.cbcalled, 0) | |
| class WeakMethodTestCase(unittest.TestCase): | |
| def _subclass(self): | |
| """Return an Object subclass overriding `some_method`.""" | |
| class C(Object): | |
| def some_method(self): | |
| return 6 | |
| return C | |
| def test_alive(self): | |
| o = Object(1) | |
| r = weakref.WeakMethod(o.some_method) | |
| self.assertIsInstance(r, weakref.ReferenceType) | |
| self.assertIsInstance(r(), type(o.some_method)) | |
| self.assertIs(r().__self__, o) | |
| self.assertIs(r().__func__, o.some_method.__func__) | |
| self.assertEqual(r()(), 4) | |
| def test_object_dead(self): | |
| o = Object(1) | |
| r = weakref.WeakMethod(o.some_method) | |
| del o | |
| gc.collect() | |
| self.assertIs(r(), None) | |
| def test_method_dead(self): | |
| C = self._subclass() | |
| o = C(1) | |
| r = weakref.WeakMethod(o.some_method) | |
| del C.some_method | |
| gc.collect() | |
| self.assertIs(r(), None) | |
| def test_callback_when_object_dead(self): | |
| # Test callback behaviour when object dies first. | |
| C = self._subclass() | |
| calls = [] | |
| def cb(arg): | |
| calls.append(arg) | |
| o = C(1) | |
| r = weakref.WeakMethod(o.some_method, cb) | |
| del o | |
| gc.collect() | |
| self.assertEqual(calls, [r]) | |
| # Callback is only called once. | |
| C.some_method = Object.some_method | |
| gc.collect() | |
| self.assertEqual(calls, [r]) | |
| def test_callback_when_method_dead(self): | |
| # Test callback behaviour when method dies first. | |
| C = self._subclass() | |
| calls = [] | |
| def cb(arg): | |
| calls.append(arg) | |
| o = C(1) | |
| r = weakref.WeakMethod(o.some_method, cb) | |
| del C.some_method | |
| gc.collect() | |
| self.assertEqual(calls, [r]) | |
| # Callback is only called once. | |
| del o | |
| gc.collect() | |
| self.assertEqual(calls, [r]) | |
| @support.cpython_only | |
| def test_no_cycles(self): | |
| # A WeakMethod doesn't create any reference cycle to itself. | |
| o = Object(1) | |
| def cb(_): | |
| pass | |
| r = weakref.WeakMethod(o.some_method, cb) | |
| wr = weakref.ref(r) | |
| del r | |
| self.assertIs(wr(), None) | |
| def test_equality(self): | |
| def _eq(a, b): | |
| self.assertTrue(a == b) | |
| self.assertFalse(a != b) | |
| def _ne(a, b): | |
| self.assertTrue(a != b) | |
| self.assertFalse(a == b) | |
| x = Object(1) | |
| y = Object(1) | |
| a = weakref.WeakMethod(x.some_method) | |
| b = weakref.WeakMethod(y.some_method) | |
| c = weakref.WeakMethod(x.other_method) | |
| d = weakref.WeakMethod(y.other_method) | |
| # Objects equal, same method | |
| _eq(a, b) | |
| _eq(c, d) | |
| # Objects equal, different method | |
| _ne(a, c) | |
| _ne(a, d) | |
| _ne(b, c) | |
| _ne(b, d) | |
| # Objects unequal, same or different method | |
| z = Object(2) | |
| e = weakref.WeakMethod(z.some_method) | |
| f = weakref.WeakMethod(z.other_method) | |
| _ne(a, e) | |
| _ne(a, f) | |
| _ne(b, e) | |
| _ne(b, f) | |
| # Compare with different types | |
| _ne(a, x.some_method) | |
| _eq(a, ALWAYS_EQ) | |
| del x, y, z | |
| gc.collect() | |
| # Dead WeakMethods compare by identity | |
| refs = a, b, c, d, e, f | |
| for q in refs: | |
| for r in refs: | |
| self.assertEqual(q == r, q is r) | |
| self.assertEqual(q != r, q is not r) | |
| def test_hashing(self): | |
| # Alive WeakMethods are hashable if the underlying object is | |
| # hashable. | |
| x = Object(1) | |
| y = Object(1) | |
| a = weakref.WeakMethod(x.some_method) | |
| b = weakref.WeakMethod(y.some_method) | |
| c = weakref.WeakMethod(y.other_method) | |
| # Since WeakMethod objects are equal, the hashes should be equal. | |
| self.assertEqual(hash(a), hash(b)) | |
| ha = hash(a) | |
| # Dead WeakMethods retain their old hash value | |
| del x, y | |
| gc.collect() | |
| self.assertEqual(hash(a), ha) | |
| self.assertEqual(hash(b), ha) | |
| # If it wasn't hashed when alive, a dead WeakMethod cannot be hashed. | |
| self.assertRaises(TypeError, hash, c) | |
| class MappingTestCase(TestBase): | |
| COUNT = 10 | |
| if support.check_sanitizer(thread=True) and support.Py_GIL_DISABLED: | |
| # Reduce iteration count to get acceptable latency | |
| NUM_THREADED_ITERATIONS = 1000 | |
| else: | |
| NUM_THREADED_ITERATIONS = 100000 | |
| def check_len_cycles(self, dict_type, cons): | |
| N = 20 | |
| items = [RefCycle() for i in range(N)] | |
| dct = dict_type(cons(o) for o in items) | |
| # Keep an iterator alive | |
| it = dct.items() | |
| try: | |
| next(it) | |
| except StopIteration: | |
| pass | |
| del items | |
| gc.collect() | |
| n1 = len(dct) | |
| del it | |
| gc.collect() | |
| n2 = len(dct) | |
| # one item may be kept alive inside the iterator | |
| self.assertIn(n1, (0, 1)) | |
| self.assertEqual(n2, 0) | |
| def test_weak_keyed_len_cycles(self): | |
| self.check_len_cycles(weakref.WeakKeyDictionary, lambda k: (k, 1)) | |
| def test_weak_valued_len_cycles(self): | |
| self.check_len_cycles(weakref.WeakValueDictionary, lambda k: (1, k)) | |
| def check_len_race(self, dict_type, cons): | |
| # Extended sanity checks for len() in the face of cyclic collection | |
| self.addCleanup(gc.set_threshold, *gc.get_threshold()) | |
| for th in range(1, 100): | |
| N = 20 | |
| gc.collect(0) | |
| gc.set_threshold(th, th, th) | |
| items = [RefCycle() for i in range(N)] | |
| dct = dict_type(cons(o) for o in items) | |
| del items | |
| # All items will be collected at next garbage collection pass | |
| it = dct.items() | |
| try: | |
| next(it) | |
| except StopIteration: | |
| pass | |
| n1 = len(dct) | |
| del it | |
| n2 = len(dct) | |
| self.assertGreaterEqual(n1, 0) | |
| self.assertLessEqual(n1, N) | |
| self.assertGreaterEqual(n2, 0) | |
| self.assertLessEqual(n2, n1) | |
| def test_weak_keyed_len_race(self): | |
| self.check_len_race(weakref.WeakKeyDictionary, lambda k: (k, 1)) | |
| def test_weak_valued_len_race(self): | |
| self.check_len_race(weakref.WeakValueDictionary, lambda k: (1, k)) | |
| def test_weak_values(self): | |
| # | |
| # This exercises d.copy(), d.items(), d[], del d[], len(d). | |
| # | |
| dict, objects = self.make_weak_valued_dict() | |
| for o in objects: | |
| self.assertEqual(weakref.getweakrefcount(o), 1) | |
| self.assertIs(o, dict[o.arg], | |
| "wrong object returned by weak dict!") | |
| items1 = list(dict.items()) | |
| items2 = list(dict.copy().items()) | |
| items1.sort() | |
| items2.sort() | |
| self.assertEqual(items1, items2, | |
| "cloning of weak-valued dictionary did not work!") | |
| del items1, items2 | |
| self.assertEqual(len(dict), self.COUNT) | |
| del objects[0] | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(len(dict), self.COUNT - 1, | |
| "deleting object did not cause dictionary update") | |
| del objects, o | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(len(dict), 0, | |
| "deleting the values did not clear the dictionary") | |
| # regression on SF bug #447152: | |
| dict = weakref.WeakValueDictionary() | |
| self.assertRaises(KeyError, dict.__getitem__, 1) | |
| dict[2] = C() | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertRaises(KeyError, dict.__getitem__, 2) | |
| def test_weak_keys(self): | |
| # | |
| # This exercises d.copy(), d.items(), d[] = v, d[], del d[], | |
| # len(d), k in d. | |
| # | |
| dict, objects = self.make_weak_keyed_dict() | |
| for o in objects: | |
| self.assertEqual(weakref.getweakrefcount(o), 1, | |
| "wrong number of weak references to %r!" % o) | |
| self.assertIs(o.arg, dict[o], | |
| "wrong object returned by weak dict!") | |
| items1 = dict.items() | |
| items2 = dict.copy().items() | |
| self.assertEqual(set(items1), set(items2), | |
| "cloning of weak-keyed dictionary did not work!") | |
| del items1, items2 | |
| self.assertEqual(len(dict), self.COUNT) | |
| del objects[0] | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(len(dict), (self.COUNT - 1), | |
| "deleting object did not cause dictionary update") | |
| del objects, o | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(len(dict), 0, | |
| "deleting the keys did not clear the dictionary") | |
| o = Object(42) | |
| dict[o] = "What is the meaning of the universe?" | |
| self.assertIn(o, dict) | |
| self.assertNotIn(34, dict) | |
| def test_weak_keyed_iters(self): | |
| dict, objects = self.make_weak_keyed_dict() | |
| self.check_iters(dict) | |
| # Test keyrefs() | |
| refs = dict.keyrefs() | |
| self.assertEqual(len(refs), len(objects)) | |
| objects2 = list(objects) | |
| for wr in refs: | |
| ob = wr() | |
| self.assertIn(ob, dict) | |
| self.assertIn(ob, dict) | |
| self.assertEqual(ob.arg, dict[ob]) | |
| objects2.remove(ob) | |
| self.assertEqual(len(objects2), 0) | |
| # Test iterkeyrefs() | |
| objects2 = list(objects) | |
| self.assertEqual(len(list(dict.keyrefs())), len(objects)) | |
| for wr in dict.keyrefs(): | |
| ob = wr() | |
| self.assertIn(ob, dict) | |
| self.assertIn(ob, dict) | |
| self.assertEqual(ob.arg, dict[ob]) | |
| objects2.remove(ob) | |
| self.assertEqual(len(objects2), 0) | |
| def test_weak_valued_iters(self): | |
| dict, objects = self.make_weak_valued_dict() | |
| self.check_iters(dict) | |
| # Test valuerefs() | |
| refs = dict.valuerefs() | |
| self.assertEqual(len(refs), len(objects)) | |
| objects2 = list(objects) | |
| for wr in refs: | |
| ob = wr() | |
| self.assertEqual(ob, dict[ob.arg]) | |
| self.assertEqual(ob.arg, dict[ob.arg].arg) | |
| objects2.remove(ob) | |
| self.assertEqual(len(objects2), 0) | |
| # Test itervaluerefs() | |
| objects2 = list(objects) | |
| self.assertEqual(len(list(dict.itervaluerefs())), len(objects)) | |
| for wr in dict.itervaluerefs(): | |
| ob = wr() | |
| self.assertEqual(ob, dict[ob.arg]) | |
| self.assertEqual(ob.arg, dict[ob.arg].arg) | |
| objects2.remove(ob) | |
| self.assertEqual(len(objects2), 0) | |
| def check_iters(self, dict): | |
| # item iterator: | |
| items = list(dict.items()) | |
| for item in dict.items(): | |
| items.remove(item) | |
| self.assertFalse(items, "items() did not touch all items") | |
| # key iterator, via __iter__(): | |
| keys = list(dict.keys()) | |
| for k in dict: | |
| keys.remove(k) | |
| self.assertFalse(keys, "__iter__() did not touch all keys") | |
| # key iterator, via iterkeys(): | |
| keys = list(dict.keys()) | |
| for k in dict.keys(): | |
| keys.remove(k) | |
| self.assertFalse(keys, "iterkeys() did not touch all keys") | |
| # value iterator: | |
| values = list(dict.values()) | |
| for v in dict.values(): | |
| values.remove(v) | |
| self.assertFalse(values, | |
| "itervalues() did not touch all values") | |
| def check_weak_destroy_while_iterating(self, dict, objects, iter_name): | |
| n = len(dict) | |
| it = iter(getattr(dict, iter_name)()) | |
| next(it) # Trigger internal iteration | |
| # Destroy an object | |
| del objects[-1] | |
| gc.collect() # just in case | |
| # We have removed either the first consumed object, or another one | |
| self.assertIn(len(list(it)), [len(objects), len(objects) - 1]) | |
| del it | |
| # The removal has been committed | |
| self.assertEqual(len(dict), n - 1) | |
| def check_weak_destroy_and_mutate_while_iterating(self, dict, testcontext): | |
| # Check that we can explicitly mutate the weak dict without | |
| # interfering with delayed removal. | |
| # `testcontext` should create an iterator, destroy one of the | |
| # weakref'ed objects and then return a new key/value pair corresponding | |
| # to the destroyed object. | |
| with testcontext() as (k, v): | |
| self.assertNotIn(k, dict) | |
| with testcontext() as (k, v): | |
| self.assertRaises(KeyError, dict.__delitem__, k) | |
| self.assertNotIn(k, dict) | |
| with testcontext() as (k, v): | |
| self.assertRaises(KeyError, dict.pop, k) | |
| self.assertNotIn(k, dict) | |
| with testcontext() as (k, v): | |
| dict[k] = v | |
| self.assertEqual(dict[k], v) | |
| ddict = copy.copy(dict) | |
| with testcontext() as (k, v): | |
| dict.update(ddict) | |
| self.assertEqual(dict, ddict) | |
| with testcontext() as (k, v): | |
| dict.clear() | |
| self.assertEqual(len(dict), 0) | |
| def check_weak_del_and_len_while_iterating(self, dict, testcontext): | |
| # Check that len() works when both iterating and removing keys | |
| # explicitly through various means (.pop(), .clear()...), while | |
| # implicit mutation is deferred because an iterator is alive. | |
| # (each call to testcontext() should schedule one item for removal | |
| # for this test to work properly) | |
| o = Object(123456) | |
| with testcontext(): | |
| n = len(dict) | |
| # Since underlying dict is ordered, first item is popped | |
| dict.pop(next(dict.keys())) | |
| self.assertEqual(len(dict), n - 1) | |
| dict[o] = o | |
| self.assertEqual(len(dict), n) | |
| # last item in objects is removed from dict in context shutdown | |
| with testcontext(): | |
| self.assertEqual(len(dict), n - 1) | |
| # Then, (o, o) is popped | |
| dict.popitem() | |
| self.assertEqual(len(dict), n - 2) | |
| with testcontext(): | |
| self.assertEqual(len(dict), n - 3) | |
| del dict[next(dict.keys())] | |
| self.assertEqual(len(dict), n - 4) | |
| with testcontext(): | |
| self.assertEqual(len(dict), n - 5) | |
| dict.popitem() | |
| self.assertEqual(len(dict), n - 6) | |
| with testcontext(): | |
| dict.clear() | |
| self.assertEqual(len(dict), 0) | |
| self.assertEqual(len(dict), 0) | |
| def test_weak_keys_destroy_while_iterating(self): | |
| # Issue #7105: iterators shouldn't crash when a key is implicitly removed | |
| dict, objects = self.make_weak_keyed_dict() | |
| self.check_weak_destroy_while_iterating(dict, objects, 'keys') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'items') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'values') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'keyrefs') | |
| dict, objects = self.make_weak_keyed_dict() | |
| @contextlib.contextmanager | |
| def testcontext(): | |
| try: | |
| it = iter(dict.items()) | |
| next(it) | |
| # Schedule a key/value for removal and recreate it | |
| v = objects.pop().arg | |
| gc.collect() # just in case | |
| yield Object(v), v | |
| finally: | |
| it = None # should commit all removals | |
| gc.collect() | |
| self.check_weak_destroy_and_mutate_while_iterating(dict, testcontext) | |
| # Issue #21173: len() fragile when keys are both implicitly and | |
| # explicitly removed. | |
| dict, objects = self.make_weak_keyed_dict() | |
| self.check_weak_del_and_len_while_iterating(dict, testcontext) | |
| def test_weak_values_destroy_while_iterating(self): | |
| # Issue #7105: iterators shouldn't crash when a key is implicitly removed | |
| dict, objects = self.make_weak_valued_dict() | |
| self.check_weak_destroy_while_iterating(dict, objects, 'keys') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'items') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'values') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'itervaluerefs') | |
| self.check_weak_destroy_while_iterating(dict, objects, 'valuerefs') | |
| dict, objects = self.make_weak_valued_dict() | |
| @contextlib.contextmanager | |
| def testcontext(): | |
| try: | |
| it = iter(dict.items()) | |
| next(it) | |
| # Schedule a key/value for removal and recreate it | |
| k = objects.pop().arg | |
| gc.collect() # just in case | |
| yield k, Object(k) | |
| finally: | |
| it = None # should commit all removals | |
| gc.collect() | |
| self.check_weak_destroy_and_mutate_while_iterating(dict, testcontext) | |
| dict, objects = self.make_weak_valued_dict() | |
| self.check_weak_del_and_len_while_iterating(dict, testcontext) | |
| def test_make_weak_keyed_dict_from_dict(self): | |
| o = Object(3) | |
| dict = weakref.WeakKeyDictionary({o:364}) | |
| self.assertEqual(dict[o], 364) | |
| def test_make_weak_keyed_dict_from_weak_keyed_dict(self): | |
| o = Object(3) | |
| dict = weakref.WeakKeyDictionary({o:364}) | |
| dict2 = weakref.WeakKeyDictionary(dict) | |
| self.assertEqual(dict[o], 364) | |
| def make_weak_keyed_dict(self): | |
| dict = weakref.WeakKeyDictionary() | |
| objects = list(map(Object, range(self.COUNT))) | |
| for o in objects: | |
| dict[o] = o.arg | |
| return dict, objects | |
| def test_make_weak_valued_dict_from_dict(self): | |
| o = Object(3) | |
| dict = weakref.WeakValueDictionary({364:o}) | |
| self.assertEqual(dict[364], o) | |
| def test_make_weak_valued_dict_from_weak_valued_dict(self): | |
| o = Object(3) | |
| dict = weakref.WeakValueDictionary({364:o}) | |
| dict2 = weakref.WeakValueDictionary(dict) | |
| self.assertEqual(dict[364], o) | |
| def test_make_weak_valued_dict_misc(self): | |
| # errors | |
| self.assertRaises(TypeError, weakref.WeakValueDictionary.__init__) | |
| self.assertRaises(TypeError, weakref.WeakValueDictionary, {}, {}) | |
| self.assertRaises(TypeError, weakref.WeakValueDictionary, (), ()) | |
| # special keyword arguments | |
| o = Object(3) | |
| for kw in 'self', 'dict', 'other', 'iterable': | |
| d = weakref.WeakValueDictionary(**{kw: o}) | |
| self.assertEqual(list(d.keys()), [kw]) | |
| self.assertEqual(d[kw], o) | |
| def make_weak_valued_dict(self): | |
| dict = weakref.WeakValueDictionary() | |
| objects = list(map(Object, range(self.COUNT))) | |
| for o in objects: | |
| dict[o.arg] = o | |
| return dict, objects | |
| def check_popitem(self, klass, key1, value1, key2, value2): | |
| weakdict = klass() | |
| weakdict[key1] = value1 | |
| weakdict[key2] = value2 | |
| self.assertEqual(len(weakdict), 2) | |
| k, v = weakdict.popitem() | |
| self.assertEqual(len(weakdict), 1) | |
| if k is key1: | |
| self.assertIs(v, value1) | |
| else: | |
| self.assertIs(v, value2) | |
| k, v = weakdict.popitem() | |
| self.assertEqual(len(weakdict), 0) | |
| if k is key1: | |
| self.assertIs(v, value1) | |
| else: | |
| self.assertIs(v, value2) | |
| def test_weak_valued_dict_popitem(self): | |
| self.check_popitem(weakref.WeakValueDictionary, | |
| "key1", C(), "key2", C()) | |
| def test_weak_keyed_dict_popitem(self): | |
| self.check_popitem(weakref.WeakKeyDictionary, | |
| C(), "value 1", C(), "value 2") | |
| def check_setdefault(self, klass, key, value1, value2): | |
| self.assertIsNot(value1, value2, | |
| "invalid test" | |
| " -- value parameters must be distinct objects") | |
| weakdict = klass() | |
| o = weakdict.setdefault(key, value1) | |
| self.assertIs(o, value1) | |
| self.assertIn(key, weakdict) | |
| self.assertIs(weakdict.get(key), value1) | |
| self.assertIs(weakdict[key], value1) | |
| o = weakdict.setdefault(key, value2) | |
| self.assertIs(o, value1) | |
| self.assertIn(key, weakdict) | |
| self.assertIs(weakdict.get(key), value1) | |
| self.assertIs(weakdict[key], value1) | |
| def test_weak_valued_dict_setdefault(self): | |
| self.check_setdefault(weakref.WeakValueDictionary, | |
| "key", C(), C()) | |
| def test_weak_keyed_dict_setdefault(self): | |
| self.check_setdefault(weakref.WeakKeyDictionary, | |
| C(), "value 1", "value 2") | |
| def check_update(self, klass, dict): | |
| # | |
| # This exercises d.update(), len(d), d.keys(), k in d, | |
| # d.get(), d[]. | |
| # | |
| weakdict = klass() | |
| weakdict.update(dict) | |
| self.assertEqual(len(weakdict), len(dict)) | |
| for k in weakdict.keys(): | |
| self.assertIn(k, dict, "mysterious new key appeared in weak dict") | |
| v = dict.get(k) | |
| self.assertIs(v, weakdict[k]) | |
| self.assertIs(v, weakdict.get(k)) | |
| for k in dict.keys(): | |
| self.assertIn(k, weakdict, "original key disappeared in weak dict") | |
| v = dict[k] | |
| self.assertIs(v, weakdict[k]) | |
| self.assertIs(v, weakdict.get(k)) | |
| def test_weak_valued_dict_update(self): | |
| self.check_update(weakref.WeakValueDictionary, | |
| {1: C(), 'a': C(), C(): C()}) | |
| # errors | |
| self.assertRaises(TypeError, weakref.WeakValueDictionary.update) | |
| d = weakref.WeakValueDictionary() | |
| self.assertRaises(TypeError, d.update, {}, {}) | |
| self.assertRaises(TypeError, d.update, (), ()) | |
| self.assertEqual(list(d.keys()), []) | |
| # special keyword arguments | |
| o = Object(3) | |
| for kw in 'self', 'dict', 'other', 'iterable': | |
| d = weakref.WeakValueDictionary() | |
| d.update(**{kw: o}) | |
| self.assertEqual(list(d.keys()), [kw]) | |
| self.assertEqual(d[kw], o) | |
| def test_weak_valued_union_operators(self): | |
| a = C() | |
| b = C() | |
| c = C() | |
| wvd1 = weakref.WeakValueDictionary({1: a}) | |
| wvd2 = weakref.WeakValueDictionary({1: b, 2: a}) | |
| wvd3 = wvd1.copy() | |
| d1 = {1: c, 3: b} | |
| pairs = [(5, c), (6, b)] | |
| tmp1 = wvd1 | wvd2 # Between two WeakValueDictionaries | |
| self.assertEqual(dict(tmp1), dict(wvd1) | dict(wvd2)) | |
| self.assertIs(type(tmp1), weakref.WeakValueDictionary) | |
| wvd1 |= wvd2 | |
| self.assertEqual(wvd1, tmp1) | |
| tmp2 = wvd2 | d1 # Between WeakValueDictionary and mapping | |
| self.assertEqual(dict(tmp2), dict(wvd2) | d1) | |
| self.assertIs(type(tmp2), weakref.WeakValueDictionary) | |
| wvd2 |= d1 | |
| self.assertEqual(wvd2, tmp2) | |
| tmp3 = wvd3.copy() # Between WeakValueDictionary and iterable key, value | |
| tmp3 |= pairs | |
| self.assertEqual(dict(tmp3), dict(wvd3) | dict(pairs)) | |
| self.assertIs(type(tmp3), weakref.WeakValueDictionary) | |
| tmp4 = d1 | wvd3 # Testing .__ror__ | |
| self.assertEqual(dict(tmp4), d1 | dict(wvd3)) | |
| self.assertIs(type(tmp4), weakref.WeakValueDictionary) | |
| del a | |
| self.assertNotIn(2, tmp1) | |
| self.assertNotIn(2, tmp2) | |
| self.assertNotIn(1, tmp3) | |
| self.assertNotIn(1, tmp4) | |
| def test_weak_keyed_dict_update(self): | |
| self.check_update(weakref.WeakKeyDictionary, | |
| {C(): 1, C(): 2, C(): 3}) | |
| d = weakref.WeakKeyDictionary() | |
| msg = ("Keyword arguments are not supported: " | |
| "cannot create weak reference to 'str' object") | |
| with self.assertRaisesRegex(TypeError, msg): | |
| d.update(k='v') | |
| def test_weak_keyed_delitem(self): | |
| d = weakref.WeakKeyDictionary() | |
| o1 = Object('1') | |
| o2 = Object('2') | |
| d[o1] = 'something' | |
| d[o2] = 'something' | |
| self.assertEqual(len(d), 2) | |
| del d[o1] | |
| self.assertEqual(len(d), 1) | |
| self.assertEqual(list(d.keys()), [o2]) | |
| def test_weak_keyed_union_operators(self): | |
| o1 = C() | |
| o2 = C() | |
| o3 = C() | |
| wkd1 = weakref.WeakKeyDictionary({o1: 1, o2: 2}) | |
| wkd2 = weakref.WeakKeyDictionary({o3: 3, o1: 4}) | |
| wkd3 = wkd1.copy() | |
| d1 = {o2: '5', o3: '6'} | |
| pairs = [(o2, 7), (o3, 8)] | |
| tmp1 = wkd1 | wkd2 # Between two WeakKeyDictionaries | |
| self.assertEqual(dict(tmp1), dict(wkd1) | dict(wkd2)) | |
| self.assertIs(type(tmp1), weakref.WeakKeyDictionary) | |
| wkd1 |= wkd2 | |
| self.assertEqual(wkd1, tmp1) | |
| tmp2 = wkd2 | d1 # Between WeakKeyDictionary and mapping | |
| self.assertEqual(dict(tmp2), dict(wkd2) | d1) | |
| self.assertIs(type(tmp2), weakref.WeakKeyDictionary) | |
| wkd2 |= d1 | |
| self.assertEqual(wkd2, tmp2) | |
| tmp3 = wkd3.copy() # Between WeakKeyDictionary and iterable key, value | |
| tmp3 |= pairs | |
| self.assertEqual(dict(tmp3), dict(wkd3) | dict(pairs)) | |
| self.assertIs(type(tmp3), weakref.WeakKeyDictionary) | |
| tmp4 = d1 | wkd3 # Testing .__ror__ | |
| self.assertEqual(dict(tmp4), d1 | dict(wkd3)) | |
| self.assertIs(type(tmp4), weakref.WeakKeyDictionary) | |
| del o1 | |
| self.assertNotIn(4, tmp1.values()) | |
| self.assertNotIn(4, tmp2.values()) | |
| self.assertNotIn(1, tmp3.values()) | |
| self.assertNotIn(1, tmp4.values()) | |
| def test_weak_valued_delitem(self): | |
| d = weakref.WeakValueDictionary() | |
| o1 = Object('1') | |
| o2 = Object('2') | |
| d['something'] = o1 | |
| d['something else'] = o2 | |
| self.assertEqual(len(d), 2) | |
| del d['something'] | |
| self.assertEqual(len(d), 1) | |
| self.assertEqual(list(d.items()), [('something else', o2)]) | |
| def test_weak_keyed_bad_delitem(self): | |
| d = weakref.WeakKeyDictionary() | |
| o = Object('1') | |
| # An attempt to delete an object that isn't there should raise | |
| # KeyError. It didn't before 2.3. | |
| self.assertRaises(KeyError, d.__delitem__, o) | |
| self.assertRaises(KeyError, d.__getitem__, o) | |
| # If a key isn't of a weakly referencable type, __getitem__ and | |
| # __setitem__ raise TypeError. __delitem__ should too. | |
| self.assertRaises(TypeError, d.__delitem__, 13) | |
| self.assertRaises(TypeError, d.__getitem__, 13) | |
| self.assertRaises(TypeError, d.__setitem__, 13, 13) | |
| def test_weak_keyed_cascading_deletes(self): | |
| # SF bug 742860. For some reason, before 2.3 __delitem__ iterated | |
| # over the keys via self.data.iterkeys(). If things vanished from | |
| # the dict during this (or got added), that caused a RuntimeError. | |
| d = weakref.WeakKeyDictionary() | |
| mutate = False | |
| class C(object): | |
| def __init__(self, i): | |
| self.value = i | |
| def __hash__(self): | |
| return hash(self.value) | |
| def __eq__(self, other): | |
| if mutate: | |
| # Side effect that mutates the dict, by removing the | |
| # last strong reference to a key. | |
| del objs[-1] | |
| return self.value == other.value | |
| objs = [C(i) for i in range(4)] | |
| for o in objs: | |
| d[o] = o.value | |
| del o # now the only strong references to keys are in objs | |
| # Find the order in which iterkeys sees the keys. | |
| objs = list(d.keys()) | |
| # Reverse it, so that the iteration implementation of __delitem__ | |
| # has to keep looping to find the first object we delete. | |
| objs.reverse() | |
| # Turn on mutation in C.__eq__. The first time through the loop, | |
| # under the iterkeys() business the first comparison will delete | |
| # the last item iterkeys() would see, and that causes a | |
| # RuntimeError: dictionary changed size during iteration | |
| # when the iterkeys() loop goes around to try comparing the next | |
| # key. After this was fixed, it just deletes the last object *our* | |
| # "for o in obj" loop would have gotten to. | |
| mutate = True | |
| count = 0 | |
| for o in objs: | |
| count += 1 | |
| del d[o] | |
| gc_collect() # For PyPy or other GCs. | |
| self.assertEqual(len(d), 0) | |
| self.assertEqual(count, 2) | |
| def test_make_weak_valued_dict_repr(self): | |
| dict = weakref.WeakValueDictionary() | |
| self.assertRegex(repr(dict), '<WeakValueDictionary at 0x.*>') | |
| def test_make_weak_keyed_dict_repr(self): | |
| dict = weakref.WeakKeyDictionary() | |
| self.assertRegex(repr(dict), '<WeakKeyDictionary at 0x.*>') | |
| @threading_helper.requires_working_threading() | |
| def test_threaded_weak_valued_setdefault(self): | |
| d = weakref.WeakValueDictionary() | |
| with collect_in_thread(): | |
| for i in range(self.NUM_THREADED_ITERATIONS): | |
| x = d.setdefault(10, RefCycle()) | |
| self.assertIsNot(x, None) # we never put None in there! | |
| del x | |
| @threading_helper.requires_working_threading() | |
| def test_threaded_weak_valued_pop(self): | |
| d = weakref.WeakValueDictionary() | |
| with collect_in_thread(): | |
| for i in range(self.NUM_THREADED_ITERATIONS): | |
| d[10] = RefCycle() | |
| x = d.pop(10, 10) | |
| self.assertIsNot(x, None) # we never put None in there! | |
| @threading_helper.requires_working_threading() | |
| def test_threaded_weak_valued_consistency(self): | |
| # Issue #28427: old keys should not remove new values from | |
| # WeakValueDictionary when collecting from another thread. | |
| d = weakref.WeakValueDictionary() | |
| with collect_in_thread(): | |
| for i in range(2 * self.NUM_THREADED_ITERATIONS): | |
| o = RefCycle() | |
| d[10] = o | |
| # o is still alive, so the dict can't be empty | |
| self.assertEqual(len(d), 1) | |
| o = None # lose ref | |
| @support.cpython_only | |
| def test_weak_valued_consistency(self): | |
| # A single-threaded, deterministic repro for issue #28427: old keys | |
| # should not remove new values from WeakValueDictionary. This relies on | |
| # an implementation detail of CPython's WeakValueDictionary (its | |
| # underlying dictionary of KeyedRefs) to reproduce the issue. | |
| d = weakref.WeakValueDictionary() | |
| with support.disable_gc(): | |
| d[10] = RefCycle() | |
| # Keep the KeyedRef alive after it's replaced so that GC will invoke | |
| # the callback. | |
| wr = d.data[10] | |
| # Replace the value with something that isn't cyclic garbage | |
| o = RefCycle() | |
| d[10] = o | |
| # Trigger GC, which will invoke the callback for `wr` | |
| gc.collect() | |
| self.assertEqual(len(d), 1) | |
| def check_threaded_weak_dict_copy(self, type_, deepcopy): | |
| # `type_` should be either WeakKeyDictionary or WeakValueDictionary. | |
| # `deepcopy` should be either True or False. | |
| exc = [] | |
| class DummyKey: | |
| def __init__(self, ctr): | |
| self.ctr = ctr | |
| class DummyValue: | |
| def __init__(self, ctr): | |
| self.ctr = ctr | |
| def dict_copy(d, exc): | |
| try: | |
| if deepcopy is True: | |
| _ = copy.deepcopy(d) | |
| else: | |
| _ = d.copy() | |
| except Exception as ex: | |
| exc.append(ex) | |
| def pop_and_collect(lst): | |
| gc_ctr = 0 | |
| while lst: | |
| i = random.randint(0, len(lst) - 1) | |
| gc_ctr += 1 | |
| lst.pop(i) | |
| if gc_ctr % 10000 == 0: | |
| gc.collect() # just in case | |
| self.assertIn(type_, (weakref.WeakKeyDictionary, weakref.WeakValueDictionary)) | |
| d = type_() | |
| keys = [] | |
| values = [] | |
| # Initialize d with many entries | |
| for i in range(70000): | |
| k, v = DummyKey(i), DummyValue(i) | |
| keys.append(k) | |
| values.append(v) | |
| d[k] = v | |
| del k | |
| del v | |
| t_copy = threading.Thread(target=dict_copy, args=(d, exc,)) | |
| if type_ is weakref.WeakKeyDictionary: | |
| t_collect = threading.Thread(target=pop_and_collect, args=(keys,)) | |
| else: # weakref.WeakValueDictionary | |
| t_collect = threading.Thread(target=pop_and_collect, args=(values,)) | |
| t_copy.start() | |
| t_collect.start() | |
| t_copy.join() | |
| t_collect.join() | |
| # Test exceptions | |
| if exc: | |
| raise exc[0] | |
| @threading_helper.requires_working_threading() | |
| @support.requires_resource('cpu') | |
| def test_threaded_weak_key_dict_copy(self): | |
| # Issue #35615: Weakref keys or values getting GC'ed during dict | |
| # copying should not result in a crash. | |
| self.check_threaded_weak_dict_copy(weakref.WeakKeyDictionary, False) | |
| @threading_helper.requires_working_threading() | |
| @support.requires_resource('cpu') | |
| def test_threaded_weak_key_dict_deepcopy(self): | |
| # Issue #35615: Weakref keys or values getting GC'ed during dict | |
| # copying should not result in a crash. | |
| self.check_threaded_weak_dict_copy(weakref.WeakKeyDictionary, True) | |
| @threading_helper.requires_working_threading() | |
| @support.requires_resource('cpu') | |
| def test_threaded_weak_value_dict_copy(self): | |
| # Issue #35615: Weakref keys or values getting GC'ed during dict | |
| # copying should not result in a crash. | |
| self.check_threaded_weak_dict_copy(weakref.WeakValueDictionary, False) | |
| @threading_helper.requires_working_threading() | |
| @support.requires_resource('cpu') | |
| def test_threaded_weak_value_dict_deepcopy(self): | |
| # Issue #35615: Weakref keys or values getting GC'ed during dict | |
| # copying should not result in a crash. | |
| self.check_threaded_weak_dict_copy(weakref.WeakValueDictionary, True) | |
| @support.cpython_only | |
| def test_remove_closure(self): | |
| d = weakref.WeakValueDictionary() | |
| self.assertIsNone(d._remove.__closure__) | |
| from test import mapping_tests | |
| class WeakValueDictionaryTestCase(mapping_tests.BasicTestMappingProtocol): | |
| """Check that WeakValueDictionary conforms to the mapping protocol""" | |
| __ref = {"key1":Object(1), "key2":Object(2), "key3":Object(3)} | |
| type2test = weakref.WeakValueDictionary | |
| def _reference(self): | |
| return self.__ref.copy() | |
| class WeakKeyDictionaryTestCase(mapping_tests.BasicTestMappingProtocol): | |
| """Check that WeakKeyDictionary conforms to the mapping protocol""" | |
| __ref = {Object("key1"):1, Object("key2"):2, Object("key3"):3} | |
| type2test = weakref.WeakKeyDictionary | |
| def _reference(self): | |
| return self.__ref.copy() | |
| class FinalizeTestCase(unittest.TestCase): | |
| class A: | |
| pass | |
| def _collect_if_necessary(self): | |
| # we create no ref-cycles so in CPython no gc should be needed | |
| if sys.implementation.name != 'cpython': | |
| support.gc_collect() | |
| def test_finalize(self): | |
| def add(x,y,z): | |
| res.append(x + y + z) | |
| return x + y + z | |
| a = self.A() | |
| res = [] | |
| f = weakref.finalize(a, add, 67, 43, z=89) | |
| self.assertEqual(f.alive, True) | |
| self.assertEqual(f.peek(), (a, add, (67,43), {'z':89})) | |
| self.assertEqual(f(), 199) | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f.peek(), None) | |
| self.assertEqual(f.detach(), None) | |
| self.assertEqual(f.alive, False) | |
| self.assertEqual(res, [199]) | |
| res = [] | |
| f = weakref.finalize(a, add, 67, 43, 89) | |
| self.assertEqual(f.peek(), (a, add, (67,43,89), {})) | |
| self.assertEqual(f.detach(), (a, add, (67,43,89), {})) | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f.peek(), None) | |
| self.assertEqual(f.detach(), None) | |
| self.assertEqual(f.alive, False) | |
| self.assertEqual(res, []) | |
| res = [] | |
| f = weakref.finalize(a, add, x=67, y=43, z=89) | |
| del a | |
| self._collect_if_necessary() | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f(), None) | |
| self.assertEqual(f.peek(), None) | |
| self.assertEqual(f.detach(), None) | |
| self.assertEqual(f.alive, False) | |
| self.assertEqual(res, [199]) | |
| def test_arg_errors(self): | |
| def fin(*args, **kwargs): | |
| res.append((args, kwargs)) | |
| a = self.A() | |
| res = [] | |
| f = weakref.finalize(a, fin, 1, 2, func=3, obj=4) | |
| self.assertEqual(f.peek(), (a, fin, (1, 2), {'func': 3, 'obj': 4})) | |
| f() | |
| self.assertEqual(res, [((1, 2), {'func': 3, 'obj': 4})]) | |
| with self.assertRaises(TypeError): | |
| weakref.finalize(a, func=fin, arg=1) | |
| with self.assertRaises(TypeError): | |
| weakref.finalize(obj=a, func=fin, arg=1) | |
| self.assertRaises(TypeError, weakref.finalize, a) | |
| self.assertRaises(TypeError, weakref.finalize) | |
| def test_order(self): | |
| a = self.A() | |
| res = [] | |
| f1 = weakref.finalize(a, res.append, 'f1') | |
| f2 = weakref.finalize(a, res.append, 'f2') | |
| f3 = weakref.finalize(a, res.append, 'f3') | |
| f4 = weakref.finalize(a, res.append, 'f4') | |
| f5 = weakref.finalize(a, res.append, 'f5') | |
| # make sure finalizers can keep themselves alive | |
| del f1, f4 | |
| self.assertTrue(f2.alive) | |
| self.assertTrue(f3.alive) | |
| self.assertTrue(f5.alive) | |
| self.assertTrue(f5.detach()) | |
| self.assertFalse(f5.alive) | |
| f5() # nothing because previously unregistered | |
| res.append('A') | |
| f3() # => res.append('f3') | |
| self.assertFalse(f3.alive) | |
| res.append('B') | |
| f3() # nothing because previously called | |
| res.append('C') | |
| del a | |
| self._collect_if_necessary() | |
| # => res.append('f4') | |
| # => res.append('f2') | |
| # => res.append('f1') | |
| self.assertFalse(f2.alive) | |
| res.append('D') | |
| f2() # nothing because previously called by gc | |
| expected = ['A', 'f3', 'B', 'C', 'f4', 'f2', 'f1', 'D'] | |
| self.assertEqual(res, expected) | |
| def test_all_freed(self): | |
| # we want a weakrefable subclass of weakref.finalize | |
| class MyFinalizer(weakref.finalize): | |
| pass | |
| a = self.A() | |
| res = [] | |
| def callback(): | |
| res.append(123) | |
| f = MyFinalizer(a, callback) | |
| wr_callback = weakref.ref(callback) | |
| wr_f = weakref.ref(f) | |
| del callback, f | |
| self.assertIsNotNone(wr_callback()) | |
| self.assertIsNotNone(wr_f()) | |
| del a | |
| self._collect_if_necessary() | |
| self.assertIsNone(wr_callback()) | |
| self.assertIsNone(wr_f()) | |
| self.assertEqual(res, [123]) | |
| @classmethod | |
| def run_in_child(cls): | |
| def error(): | |
| # Create an atexit finalizer from inside a finalizer called | |
| # at exit. This should be the next to be run. | |
| g1 = weakref.finalize(cls, print, 'g1') | |
| print('f3 error') | |
| 1/0 | |
| # cls should stay alive till atexit callbacks run | |
| f1 = weakref.finalize(cls, print, 'f1', _global_var) | |
| f2 = weakref.finalize(cls, print, 'f2', _global_var) | |
| f3 = weakref.finalize(cls, error) | |
| f4 = weakref.finalize(cls, print, 'f4', _global_var) | |
| assert f1.atexit == True | |
| f2.atexit = False | |
| assert f3.atexit == True | |
| assert f4.atexit == True | |
| def test_atexit(self): | |
| prog = ('from test.test_weakref import FinalizeTestCase;'+ | |
| 'FinalizeTestCase.run_in_child()') | |
| rc, out, err = script_helper.assert_python_ok('-c', prog) | |
| out = out.decode('ascii').splitlines() | |
| self.assertEqual(out, ['f4 foobar', 'f3 error', 'g1', 'f1 foobar']) | |
| self.assertTrue(b'ZeroDivisionError' in err) | |
| class ModuleTestCase(unittest.TestCase): | |
| def test_names(self): | |
| for name in ('ReferenceType', 'ProxyType', 'CallableProxyType', | |
| 'WeakMethod', 'WeakSet', 'WeakKeyDictionary', 'WeakValueDictionary'): | |
| obj = getattr(weakref, name) | |
| if name != 'WeakSet': | |
| self.assertEqual(obj.__module__, 'weakref') | |
| self.assertEqual(obj.__name__, name) | |
| self.assertEqual(obj.__qualname__, name) | |
| libreftest = """ Doctest for examples in the library reference: weakref.rst | |
| >>> from test.support import gc_collect | |
| >>> import weakref | |
| >>> class Dict(dict): | |
| ... pass | |
| ... | |
| >>> obj = Dict(red=1, green=2, blue=3) # this object is weak referencable | |
| >>> r = weakref.ref(obj) | |
| >>> print(r() is obj) | |
| True | |
| >>> import weakref | |
| >>> class Object: | |
| ... pass | |
| ... | |
| >>> o = Object() | |
| >>> r = weakref.ref(o) | |
| >>> o2 = r() | |
| >>> o is o2 | |
| True | |
| >>> del o, o2 | |
| >>> gc_collect() # For PyPy or other GCs. | |
| >>> print(r()) | |
| None | |
| >>> import weakref | |
| >>> class ExtendedRef(weakref.ref): | |
| ... def __init__(self, ob, callback=None, **annotations): | |
| ... super().__init__(ob, callback) | |
| ... self.__counter = 0 | |
| ... for k, v in annotations.items(): | |
| ... setattr(self, k, v) | |
| ... def __call__(self): | |
| ... '''Return a pair containing the referent and the number of | |
| ... times the reference has been called. | |
| ... ''' | |
| ... ob = super().__call__() | |
| ... if ob is not None: | |
| ... self.__counter += 1 | |
| ... ob = (ob, self.__counter) | |
| ... return ob | |
| ... | |
| >>> class A: # not in docs from here, just testing the ExtendedRef | |
| ... pass | |
| ... | |
| >>> a = A() | |
| >>> r = ExtendedRef(a, foo=1, bar="baz") | |
| >>> r.foo | |
| 1 | |
| >>> r.bar | |
| 'baz' | |
| >>> r()[1] | |
| 1 | |
| >>> r()[1] | |
| 2 | |
| >>> r()[0] is a | |
| True | |
| >>> import weakref | |
| >>> _id2obj_dict = weakref.WeakValueDictionary() | |
| >>> def remember(obj): | |
| ... oid = id(obj) | |
| ... _id2obj_dict[oid] = obj | |
| ... return oid | |
| ... | |
| >>> def id2obj(oid): | |
| ... return _id2obj_dict[oid] | |
| ... | |
| >>> a = A() # from here, just testing | |
| >>> a_id = remember(a) | |
| >>> id2obj(a_id) is a | |
| True | |
| >>> del a | |
| >>> gc_collect() # For PyPy or other GCs. | |
| >>> try: | |
| ... id2obj(a_id) | |
| ... except KeyError: | |
| ... print('OK') | |
| ... else: | |
| ... print('WeakValueDictionary error') | |
| OK | |
| """ | |
| __test__ = {'libreftest' : libreftest} | |
| def load_tests(loader, tests, pattern): | |
| tests.addTest(doctest.DocTestSuite()) | |
| return tests | |
| if __name__ == "__main__": | |
| unittest.main() |