cpython/Lib/test/test_threading_local.py

167 lines
4.4 KiB
Python

import unittest
from doctest import DocTestSuite
from test import support
import weakref
import gc
# Modules under test
_thread = support.import_module('_thread')
threading = 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():
nonlocal passed
# 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 = 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)
def test_arguments(self):
# Issue 1522237
class MyLocal(self._local):
def __init__(self, *args, **kwargs):
pass
MyLocal(a=1)
MyLocal(1)
self.assertRaises(TypeError, self._local, a=1)
self.assertRaises(TypeError, self._local, 1)
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))
local_orig = _threading_local.local
def setUp(test):
_threading_local.local = _thread._local
def tearDown(test):
_threading_local.local = local_orig
suite.addTest(DocTestSuite('_threading_local',
setUp=setUp, tearDown=tearDown)
)
support.run_unittest(suite)
if __name__ == '__main__':
test_main()