1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
from test_support import verbose, TestFailed
import gc
def run_test(name, thunk):
if verbose:
print "testing %s..." % name,
try:
thunk()
except TestFailed:
if verbose:
print "failed (expected %s but got %s)" % (result,
test_result)
raise TestFailed, name
else:
if verbose:
print "ok"
def test_list():
l = []
l.append(l)
gc.collect()
del l
if gc.collect() != 1:
raise TestFailed
def test_dict():
d = {}
d[1] = d
gc.collect()
del d
if gc.collect() != 1:
raise TestFailed
def test_tuple():
# since tuples are immutable we close the loop with a list
l = []
t = (l,)
l.append(t)
gc.collect()
del t
del l
if gc.collect() != 2:
raise TestFailed
def test_class():
class A:
pass
A.a = A
gc.collect()
del A
if gc.collect() == 0:
raise TestFailed
def test_instance():
class A:
pass
a = A()
a.a = a
gc.collect()
del a
if gc.collect() == 0:
raise TestFailed
def test_method():
# Tricky: self.__init__ is a bound method, it references the instance.
class A:
def __init__(self):
self.init = self.__init__
a = A()
gc.collect()
del a
if gc.collect() == 0:
raise TestFailed
def test_finalizer():
# 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
if gc.collect() == 0:
raise TestFailed
for obj in gc.garbage:
if id(obj) == id_a:
del obj.a
break
else:
raise TestFailed
gc.garbage.remove(obj)
def test_function():
# Tricky: f -> d -> f, code should call d.clear() after the exec to
# break the cycle.
d = {}
exec("def f(): pass\n") in d
gc.collect()
del d
if gc.collect() != 2:
raise TestFailed
def test_saveall():
# Verify that cyclic garbage like lists show up in gc.garbage if the
# SAVEALL option is enabled.
debug = gc.get_debug()
gc.set_debug(debug | gc.DEBUG_SAVEALL)
l = []
l.append(l)
id_l = id(l)
del l
gc.collect()
try:
for obj in gc.garbage:
if id(obj) == id_l:
del obj[:]
break
else:
raise TestFailed
gc.garbage.remove(obj)
finally:
gc.set_debug(debug)
def test_del():
# __del__ methods can trigger collection, make this to happen
thresholds = gc.get_threshold()
gc.enable()
gc.set_threshold(1)
class A:
def __del__(self):
dir(self)
a = A()
del a
gc.disable()
apply(gc.set_threshold, thresholds)
def test_all():
run_test("lists", test_list)
run_test("dicts", test_dict)
run_test("tuples", test_tuple)
run_test("classes", test_class)
run_test("instances", test_instance)
run_test("methods", test_method)
run_test("functions", test_function)
run_test("finalizers", test_finalizer)
run_test("__del__", test_del)
run_test("saveall", test_saveall)
def test():
if verbose:
print "disabling automatic collection"
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:
test_all()
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()
test()
|
