Python gc.garbage() Examples

def GClector(self):
        print('GC is invoked, %d calls in map' % len(self.ccmap))
        if self.debug_mode:
            print(self.global_config['_sip_tm'].tclient, self.global_config['_sip_tm'].tserver)
            for cc in tuple(self.ccmap):
                try:
                    print(cc.uaA.state, cc.uaO.state)
                except AttributeError:
                    print(None)
        else:
            print('[%d]: %d client, %d server transactions in memory' % \
              (os.getpid(), len(self.global_config['_sip_tm'].tclient), len(self.global_config['_sip_tm'].tserver)))
        if self.safe_restart:
            if len(self.ccmap) == 0:
                self.global_config['_sip_tm'].userv.close()
                os.chdir(self.global_config['_orig_cwd'])
                argv = [sys.executable,]
                argv.extend(self.global_config['_orig_argv'])
                os.execv(sys.executable, argv)
                # Should not reach this point!
            self.el.ival = 1
        #print gc.collect()
        if len(gc.garbage) > 0:
            print(gc.garbage) 

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_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_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_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_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_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_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_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_doesntBleed(self):
        """
        Forcing garbage collection in the test should mean that there are
        no unreachable cycles immediately after the test completes.
        """
        result = reporter.TestResult()
        self.test1(result)
        self.flushLoggedErrors() # test1 logs errors that get caught be us.
        # test1 created unreachable cycle.
        # it & all others should have been collected by now.
        if _PY3:
            n = len(gc.garbage)
        else:
            n = gc.collect()
        self.assertEqual(n, 0, 'unreachable cycle still existed')
        # check that last gc.collect didn't log more errors
        x = self.flushLoggedErrors()
        self.assertEqual(len(x), 0, 'Errors logged after gc.collect') 

def cleanup_traceback(self):
        """Remove local variables reference from tracebacks to allow garbage
        collector to clean all Qubes*() objects, otherwise file descriptors
        held by them will leak"""
        exc_infos = [e for test_case, e in self._outcome.errors
                     if test_case is self]
        if self._outcome.expectedFailure:
            exc_infos.append(self._outcome.expectedFailure)
        for exc_info in exc_infos:
            if exc_info is None:
                continue
            ex = exc_info[1]
            while ex is not None:
                if isinstance(ex, qubes.exc.QubesVMError):
                    ex.vm = None
                traceback.clear_frames(ex.__traceback__)
                ex = ex.__context__ 

def cleanup_gc(self):
        gc.collect()
        leaked = [obj for obj in gc.get_objects() + gc.garbage
                  if isinstance(obj,
                                (qubes.Qubes, qubes.vm.BaseVM,
                                 libvirt.virConnect, libvirt.virDomain))]

        if leaked:
            try:
                import objgraph
                objgraph.show_backrefs(leaked,
                                       max_depth=15, extra_info=extra_info,
                                       filename='/tmp/objgraph-{}.png'.format(
                                           self.id()))
            except ImportError:
                pass

        # do not keep leaked object references in locals()
        leaked = bool(leaked)
        assert not leaked 

def test_it(collectible):

    dd()
    dd('======= ', ('collectible' if collectible else 'uncollectible'), ' object =======')
    dd()

    gc.collect()
    dd('*** init,     nr of referrers: ', len(gc.get_referrers(One)))
    dd('              garbage:         ', gc.garbage)

    one = One(collectible)
    dd('              created:         ', one.typ, ': ', one)
    dd('              nr of referrers: ', len(gc.get_referrers(One)))

    dd('              delete:')
    del one

    gc.collect()

    dd('*** after gc, nr of referrers: ', len(gc.get_referrers(One)))
    dd('              garbage:         ', gc.garbage) 

def clear(self):
        if self._eqcache:
            eqc = self._eqcache
            self._eqcache = {}
            while eqc:
                name, obj = eqc.popitem()
                try:
                    obj.clear()
                except:
                    logging.exception_error("environment clear: {!r}".format(obj))
        gc.collect()
        for obj in gc.garbage:
            try:
                obj.close()
            except:
                logging.exception_warning("environment garbage collect: {!r}".format(obj))
        del gc.garbage[:]
        scheduler.sleep(2) # some devices need time to fully clear or disconnect 

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 countObjects(self, ao):
        """
        Recursively find non-list,dict, tuple objects in containers.

        Essential for traversing the garbage collector
        """
        itemType = type(ao)
        counter = self[itemType]
        if counter.add(ao):
            self.count += 1
            if self.count % 100000 == 0:
                runLog.info("Counted {} items".format(self.count))
            if isinstance(ao, dict):
                for k, v in ao.items():
                    self.countObjects(k)
                    self.countObjects(v)
            elif isinstance(ao, (list, tuple, set)):
                for v in iter(ao):
                    self.countObjects(v) 

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)