def test_boom2_new(self):
class Boom2_New(object):
def __init__(self):
self.x = 0
def __getattr__(self, someattribute):
self.x += 1
if self.x > 1:
del self.attr
raise AttributeError
a = Boom2_New()
b = Boom2_New()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
python类garbage()的实例源码
def tearDown(self):
# Restore gc state
del self.visit
gc.callbacks.remove(self.cb1)
gc.callbacks.remove(self.cb2)
gc.set_debug(self.debug)
if self.enabled:
gc.enable()
# destroy any uncollectables
gc.collect()
for obj in gc.garbage:
if isinstance(obj, Uncollectable):
obj.partner = None
del gc.garbage[:]
del self.othergarbage
gc.collect()
def test_main():
enabled = gc.isenabled()
gc.disable()
assert not gc.isenabled()
debug = gc.get_debug()
gc.set_debug(debug & ~gc.DEBUG_LEAK) # this test is supposed to leak
try:
gc.collect() # Delete 2nd generation garbage
run_unittest(GCTests, GCTogglingTests, GCCallbackTests)
finally:
gc.set_debug(debug)
# test gc.enable() even if GC is disabled by default
if verbose:
print("restoring automatic collection")
# make sure to always test gc.enable()
gc.enable()
assert gc.isenabled()
if not enabled:
gc.disable()
def __init__(self, interval=1.0, debug=False):
"""
Initializes garbage collector
@param interval float: timeout interval in seconds. Default: 1s
@param debug bool: debug output. Default: False
"""
super().__init__()
self.debug = debug
if debug:
gc.set_debug(gc.DEBUG_LEAK)
self.timer = QTimer()
self.timer.timeout.connect(self.check)
self.threshold = gc.get_threshold()
gc.disable()
self.timer.start(interval * 1000)
def check(self):
"""
Method called by the garbage collector timer to check if there is
something to collect.
"""
# return self.debug_cycles() # uncomment to just debug cycles
l0, l1, l2 = gc.get_count()
if self.debug:
logger.debug('gc_check called: {0} {1} {2}'.format(l0, l1, l2))
if l0 > self.threshold[0]:
num = gc.collect(0)
if self.debug:
logger.debug('collecting gen 0, found: {0:d} unreachable'
''.format(num))
if l1 > self.threshold[1]:
num = gc.collect(1)
if self.debug:
logger.debug('collecting gen 1, found: {0:d} unreachable'
''.format(num))
if l2 > self.threshold[2]:
num = gc.collect(2)
if self.debug:
logger.debug('collecting gen 2, found: {0:d} '
'unreachable'.format(num))
def test_garbageCollectedTransactionAborts(self):
"""
When an L{IAsyncTransaction} is garbage collected, it ought to abort
itself.
"""
t = self.createTransaction()
self.resultOf(t.execSQL("echo", []))
conns = self.factory.connections
self.assertEquals(len(conns), 1)
self.assertEquals(conns[0]._rollbackCount, 0)
del t
gc.collect()
self.flushHolders()
self.assertEquals(len(conns), 1)
self.assertEquals(conns[0]._rollbackCount, 1)
self.assertEquals(conns[0]._commitCount, 0)
def test_finalizer(self):
# A() is uncollectable if it is part of a cycle, make sure it shows up
# in gc.garbage.
class A:
def __del__(self): pass
class B:
pass
a = A()
a.a = a
id_a = id(a)
b = B()
b.b = b
gc.collect()
del a
del b
self.assertNotEqual(gc.collect(), 0)
for obj in gc.garbage:
if id(obj) == id_a:
del obj.a
break
else:
self.fail("didn't find obj in garbage (finalizer)")
gc.garbage.remove(obj)
def test_finalizer_newclass(self):
# A() is uncollectable if it is part of a cycle, make sure it shows up
# in gc.garbage.
class A(object):
def __del__(self): pass
class B(object):
pass
a = A()
a.a = a
id_a = id(a)
b = B()
b.b = b
gc.collect()
del a
del b
self.assertNotEqual(gc.collect(), 0)
for obj in gc.garbage:
if id(obj) == id_a:
del obj.a
break
else:
self.fail("didn't find obj in garbage (finalizer)")
gc.garbage.remove(obj)
def test_saveall(self):
# Verify that cyclic garbage like lists show up in gc.garbage if the
# SAVEALL option is enabled.
# First make sure we don't save away other stuff that just happens to
# be waiting for collection.
gc.collect()
# if this fails, someone else created immortal trash
self.assertEqual(gc.garbage, [])
L = []
L.append(L)
id_L = id(L)
debug = gc.get_debug()
gc.set_debug(debug | gc.DEBUG_SAVEALL)
del L
gc.collect()
gc.set_debug(debug)
self.assertEqual(len(gc.garbage), 1)
obj = gc.garbage.pop()
self.assertEqual(id(obj), id_L)
def test_boom(self):
class Boom:
def __getattr__(self, someattribute):
del self.attr
raise AttributeError
a = Boom()
b = Boom()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
# a<->b are in a trash cycle now. Collection will invoke
# Boom.__getattr__ (to see whether a and b have __del__ methods), and
# __getattr__ deletes the internal "attr" attributes as a side effect.
# That causes the trash cycle to get reclaimed via refcounts falling to
# 0, thus mutating the trash graph as a side effect of merely asking
# whether __del__ exists. This used to (before 2.3b1) crash Python.
# Now __getattr__ isn't called.
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def test_boom_new(self):
# boom__new and boom2_new are exactly like boom and boom2, except use
# new-style classes.
class Boom_New(object):
def __getattr__(self, someattribute):
del self.attr
raise AttributeError
a = Boom_New()
b = Boom_New()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def test_boom2_new(self):
class Boom2_New(object):
def __init__(self):
self.x = 0
def __getattr__(self, someattribute):
self.x += 1
if self.x > 1:
del self.attr
raise AttributeError
a = Boom2_New()
b = Boom2_New()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def test_main():
enabled = gc.isenabled()
gc.disable()
assert not gc.isenabled()
debug = gc.get_debug()
gc.set_debug(debug & ~gc.DEBUG_LEAK) # this test is supposed to leak
try:
gc.collect() # Delete 2nd generation garbage
run_unittest(GCTests, GCTogglingTests)
finally:
gc.set_debug(debug)
# test gc.enable() even if GC is disabled by default
if verbose:
print "restoring automatic collection"
# make sure to always test gc.enable()
gc.enable()
assert gc.isenabled()
if not enabled:
gc.disable()
def test_legacy_finalizer(self):
# A() is uncollectable if it is part of a cycle, make sure it shows up
# in gc.garbage.
@with_tp_del
class A:
def __tp_del__(self): pass
class B:
pass
a = A()
a.a = a
id_a = id(a)
b = B()
b.b = b
gc.collect()
del a
del b
self.assertNotEqual(gc.collect(), 0)
for obj in gc.garbage:
if id(obj) == id_a:
del obj.a
break
else:
self.fail("didn't find obj in garbage (finalizer)")
gc.garbage.remove(obj)
def test_legacy_finalizer_newclass(self):
# A() is uncollectable if it is part of a cycle, make sure it shows up
# in gc.garbage.
@with_tp_del
class A(object):
def __tp_del__(self): pass
class B(object):
pass
a = A()
a.a = a
id_a = id(a)
b = B()
b.b = b
gc.collect()
del a
del b
self.assertNotEqual(gc.collect(), 0)
for obj in gc.garbage:
if id(obj) == id_a:
del obj.a
break
else:
self.fail("didn't find obj in garbage (finalizer)")
gc.garbage.remove(obj)
def test_saveall(self):
# Verify that cyclic garbage like lists show up in gc.garbage if the
# SAVEALL option is enabled.
# First make sure we don't save away other stuff that just happens to
# be waiting for collection.
gc.collect()
# if this fails, someone else created immortal trash
self.assertEqual(gc.garbage, [])
L = []
L.append(L)
id_L = id(L)
debug = gc.get_debug()
gc.set_debug(debug | gc.DEBUG_SAVEALL)
del L
gc.collect()
gc.set_debug(debug)
self.assertEqual(len(gc.garbage), 1)
obj = gc.garbage.pop()
self.assertEqual(id(obj), id_L)
def test_boom(self):
class Boom:
def __getattr__(self, someattribute):
del self.attr
raise AttributeError
a = Boom()
b = Boom()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
# a<->b are in a trash cycle now. Collection will invoke
# Boom.__getattr__ (to see whether a and b have __del__ methods), and
# __getattr__ deletes the internal "attr" attributes as a side effect.
# That causes the trash cycle to get reclaimed via refcounts falling to
# 0, thus mutating the trash graph as a side effect of merely asking
# whether __del__ exists. This used to (before 2.3b1) crash Python.
# Now __getattr__ isn't called.
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def test_boom_new(self):
# boom__new and boom2_new are exactly like boom and boom2, except use
# new-style classes.
class Boom_New(object):
def __getattr__(self, someattribute):
del self.attr
raise AttributeError
a = Boom_New()
b = Boom_New()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def test_boom2_new(self):
class Boom2_New(object):
def __init__(self):
self.x = 0
def __getattr__(self, someattribute):
self.x += 1
if self.x > 1:
del self.attr
raise AttributeError
a = Boom2_New()
b = Boom2_New()
a.attr = b
b.attr = a
gc.collect()
garbagelen = len(gc.garbage)
del a, b
self.assertEqual(gc.collect(), 4)
self.assertEqual(len(gc.garbage), garbagelen)
def tearDown(self):
# Restore gc state
del self.visit
gc.callbacks.remove(self.cb1)
gc.callbacks.remove(self.cb2)
gc.set_debug(self.debug)
if self.enabled:
gc.enable()
# destroy any uncollectables
gc.collect()
for obj in gc.garbage:
if isinstance(obj, Uncollectable):
obj.partner = None
del gc.garbage[:]
del self.othergarbage
gc.collect()
