import unittest
from doctest import DocTestSuite
from test import test_support
import weakref
import gc
# Modules under test
_thread = test_support.import_module('thread')
threading = test_support.import_module('threading')
import _threading_local
class Weak(object):
pass
def target(local, weaklist):
weak = Weak()
local.weak = weak
weaklist.append(weakref.ref(weak))
class BaseLocalTest:
def test_local_refs(self):
self._local_refs(20)
self._local_refs(50)
self._local_refs(100)
def _local_refs(self, n):
local = self._local()
weaklist = []
for i in range(n):
t = threading.Thread(target=target, args=(local, weaklist))
t.start()
t.join()
del t
gc.collect()
self.assertEqual(len(weaklist), n)
# XXX _threading_local keeps the local of the last stopped thread alive.
deadlist = [weak for weak in weaklist if weak() is None]
self.assertIn(len(deadlist), (n-1, n))
# Assignment to the same thread local frees it sometimes (!)
local.someothervar = None
gc.collect()
deadlist = [weak for weak in weaklist if weak() is None]
self.assertIn(len(deadlist), (n-1, n), (n, len(deadlist)))
def test_derived(self):
# Issue 3088: if there is a threads switch inside the __init__
# of a threading.local derived class, the per-thread dictionary
# is created but not correctly set on the object.
# The first member set may be bogus.
import time
class Local(self._local):
def __init__(self):
time.sleep(0.01)
local = Local()
def f(i):
local.x = i
# Simply check that the variable is correctly set
self.assertEqual(local.x, i)
threads= []
for i in range(10):
t = threading.Thread(target=f, args=(i,))
t.start()
threads.append(t)
for t in threads:
t.join()
def test_derived_cycle_dealloc(self):
# http://bugs.python.org/issue6990
class Local(self._local):
pass
locals = None
passed = [False]
e1 = threading.Event()
e2 = threading.Event()
def f():
# 1) Involve Local in a cycle
cycle = [Local()]
cycle.append(cycle)
cycle[0].foo = 'bar'
# 2) GC the cycle (triggers threadmodule.c::local_clear
# before local_dealloc)
del cycle
gc.collect()
e1.set()
e2.wait()
# 4) New Locals should be empty
passed[0] = all(not hasattr(local, 'foo') for local in locals)
t = threading.Thread(target=f)
t.start()
e1.wait()
# 3) New Locals should recycle the original's address. Creating
# them in the thread overwrites the thread state and avoids the
# bug
locals = [Local() for i in range(10)]
e2.set()
t.join()
self.assertTrue(passed[0])
def test_arguments(self):
# Issue 1522237
from thread import _local as local
from _threading_local import local as py_local
for cls in (local, py_local):
class MyLocal(cls):
def __init__(self, *args, **kwargs):
pass
MyLocal(a=1)
MyLocal(1)
self.assertRaises(TypeError, cls, a=1)
self.assertRaises(TypeError, cls, 1)
def _test_one_class(self, c):
self._failed = "No error message set or cleared."
obj = c()
e1 = threading.Event()
e2 = threading.Event()
def f1():
obj.x = 'foo'
obj.y = 'bar'
del obj.y
e1.set()
e2.wait()
def f2():
try:
foo = obj.x
except AttributeError:
# This is expected -- we haven't set obj.x in this thread yet!
self._failed = "" # passed
else:
self._failed = ('Incorrectly got value %r from class %r\n' %
(foo, c))
sys.stderr.write(self._failed)
t1 = threading.Thread(target=f1)
t1.start()
e1.wait()
t2 = threading.Thread(target=f2)
t2.start()
t2.join()
# The test is done; just let t1 know it can exit, and wait for it.
e2.set()
t1.join()
self.assertFalse(self._failed, self._failed)
def test_threading_local(self):
self._test_one_class(self._local)
def test_threading_local_subclass(self):
class LocalSubclass(self._local):
"""To test that subclasses behave properly."""
self._test_one_class(LocalSubclass)
def _test_dict_attribute(self, cls):
obj = cls()
obj.x = 5
self.assertEqual(obj.__dict__, {'x': 5})
with self.assertRaises(AttributeError):
obj.__dict__ = {}
with self.assertRaises(AttributeError):
del obj.__dict__
def test_dict_attribute(self):
self._test_dict_attribute(self._local)
def test_dict_attribute_subclass(self):
class LocalSubclass(self._local):
"""To test that subclasses behave properly."""
self._test_dict_attribute(LocalSubclass)
class ThreadLocalTest(unittest.TestCase, BaseLocalTest):
_local = _thread._local
# Fails for the pure Python implementation
def test_cycle_collection(self):
class X:
pass
x = X()
x.local = self._local()
x.local.x = x
wr = weakref.ref(x)
del x
gc.collect()
self.assertIs(wr(), None)
class PyThreadingLocalTest(unittest.TestCase, BaseLocalTest):
_local = _threading_local.local
def test_main():
suite = unittest.TestSuite()
suite.addTest(DocTestSuite('_threading_local'))
suite.addTest(unittest.makeSuite(ThreadLocalTest))
suite.addTest(unittest.makeSuite(PyThreadingLocalTest))
try:
from thread import _local
except ImportError:
pass
else:
import _threading_local
local_orig = _threading_local.local
def setUp(test):
_threading_local.local = _local
def tearDown(test):
_threading_local.local = local_orig
suite.addTest(DocTestSuite('_threading_local',
setUp=setUp, tearDown=tearDown)
)
test_support.run_unittest(suite)
if __name__ == '__main__':
test_main()