lib-python.2.5.test.test_contextlib.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
"""Unit tests for contextlib.py, and other context managers."""
from __future__ import with_statement
import sys
import os
import decimal
import tempfile
import unittest
import threading
from contextlib import * # Tests __all__
from test.test_support import run_suite
class ContextManagerTestCase(unittest.TestCase):
def test_contextmanager_plain(self):
state = []
@contextmanager
def woohoo():
state.append(1)
yield 42
state.append(999)
with woohoo() as x:
self.assertEqual(state, [1])
self.assertEqual(x, 42)
state.append(x)
self.assertEqual(state, [1, 42, 999])
def test_contextmanager_finally(self):
state = []
@contextmanager
def woohoo():
state.append(1)
try:
yield 42
finally:
state.append(999)
try:
with woohoo() as x:
self.assertEqual(state, [1])
self.assertEqual(x, 42)
state.append(x)
raise ZeroDivisionError()
except ZeroDivisionError:
pass
else:
self.fail("Expected ZeroDivisionError")
self.assertEqual(state, [1, 42, 999])
def test_contextmanager_no_reraise(self):
@contextmanager
def whee():
yield
ctx = whee()
ctx.__enter__()
# Calling __exit__ should not result in an exception
self.failIf(ctx.__exit__(TypeError, TypeError("foo"), None))
def test_contextmanager_trap_yield_after_throw(self):
@contextmanager
def whoo():
try:
yield
except:
yield
ctx = whoo()
ctx.__enter__()
self.assertRaises(
RuntimeError, ctx.__exit__, TypeError, TypeError("foo"), None
)
def test_contextmanager_except(self):
state = []
@contextmanager
def woohoo():
state.append(1)
try:
yield 42
except ZeroDivisionError, e:
state.append(e.args[0])
self.assertEqual(state, [1, 42, 999])
with woohoo() as x:
self.assertEqual(state, [1])
self.assertEqual(x, 42)
state.append(x)
raise ZeroDivisionError(999)
self.assertEqual(state, [1, 42, 999])
def test_contextmanager_attribs(self):
def attribs(**kw):
def decorate(func):
for k,v in kw.items():
setattr(func,k,v)
return func
return decorate
@contextmanager
@attribs(foo='bar')
def baz(spam):
"""Whee!"""
self.assertEqual(baz.__name__,'baz')
self.assertEqual(baz.foo, 'bar')
self.assertEqual(baz.__doc__, "Whee!")
class NestedTestCase(unittest.TestCase):
# XXX This needs more work
def test_nested(self):
@contextmanager
def a():
yield 1
@contextmanager
def b():
yield 2
@contextmanager
def c():
yield 3
with nested(a(), b(), c()) as (x, y, z):
self.assertEqual(x, 1)
self.assertEqual(y, 2)
self.assertEqual(z, 3)
def test_nested_cleanup(self):
state = []
@contextmanager
def a():
state.append(1)
try:
yield 2
finally:
state.append(3)
@contextmanager
def b():
state.append(4)
try:
yield 5
finally:
state.append(6)
try:
with nested(a(), b()) as (x, y):
state.append(x)
state.append(y)
1/0
except ZeroDivisionError:
self.assertEqual(state, [1, 4, 2, 5, 6, 3])
else:
self.fail("Didn't raise ZeroDivisionError")
def test_nested_right_exception(self):
state = []
@contextmanager
def a():
yield 1
class b(object):
def __enter__(self):
return 2
def __exit__(self, *exc_info):
try:
raise Exception()
except:
pass
try:
with nested(a(), b()) as (x, y):
1/0
except ZeroDivisionError:
self.assertEqual((x, y), (1, 2))
except Exception:
self.fail("Reraised wrong exception")
else:
self.fail("Didn't raise ZeroDivisionError")
def test_nested_b_swallows(self):
@contextmanager
def a():
yield
@contextmanager
def b():
try:
yield
except:
# Swallow the exception
pass
try:
with nested(a(), b()):
1/0
except ZeroDivisionError:
self.fail("Didn't swallow ZeroDivisionError")
def test_nested_break(self):
@contextmanager
def a():
yield
state = 0
while True:
state += 1
with nested(a(), a()):
break
state += 10
self.assertEqual(state, 1)
def test_nested_continue(self):
@contextmanager
def a():
yield
state = 0
while state < 3:
state += 1
with nested(a(), a()):
continue
state += 10
self.assertEqual(state, 3)
def test_nested_return(self):
@contextmanager
def a():
try:
yield
except:
pass
def foo():
with nested(a(), a()):
return 1
return 10
self.assertEqual(foo(), 1)
class ClosingTestCase(unittest.TestCase):
# XXX This needs more work
def test_closing(self):
state = []
class C:
def close(self):
state.append(1)
x = C()
self.assertEqual(state, [])
with closing(x) as y:
self.assertEqual(x, y)
self.assertEqual(state, [1])
def test_closing_error(self):
state = []
class C:
def close(self):
state.append(1)
x = C()
self.assertEqual(state, [])
try:
with closing(x) as y:
self.assertEqual(x, y)
1/0
except ZeroDivisionError:
self.assertEqual(state, [1])
else:
self.fail("Didn't raise ZeroDivisionError")
class FileContextTestCase(unittest.TestCase):
def testWithOpen(self):
tfn = tempfile.mktemp()
try:
f = None
with open(tfn, "w") as f:
self.failIf(f.closed)
f.write("Booh\n")
self.failUnless(f.closed)
f = None
try:
with open(tfn, "r") as f:
self.failIf(f.closed)
self.assertEqual(f.read(), "Booh\n")
1/0
except ZeroDivisionError:
self.failUnless(f.closed)
else:
self.fail("Didn't raise ZeroDivisionError")
finally:
try:
os.remove(tfn)
except os.error:
pass
class LockContextTestCase(unittest.TestCase):
def boilerPlate(self, lock, locked):
self.failIf(locked())
with lock:
self.failUnless(locked())
self.failIf(locked())
try:
with lock:
self.failUnless(locked())
1/0
except ZeroDivisionError:
self.failIf(locked())
else:
self.fail("Didn't raise ZeroDivisionError")
def testWithLock(self):
lock = threading.Lock()
self.boilerPlate(lock, lock.locked)
def testWithRLock(self):
lock = threading.RLock()
self.boilerPlate(lock, lock._is_owned)
def testWithCondition(self):
lock = threading.Condition()
def locked():
return lock._is_owned()
self.boilerPlate(lock, locked)
def testWithSemaphore(self):
lock = threading.Semaphore()
def locked():
if lock.acquire(False):
lock.release()
return False
else:
return True
self.boilerPlate(lock, locked)
def testWithBoundedSemaphore(self):
lock = threading.BoundedSemaphore()
def locked():
if lock.acquire(False):
lock.release()
return False
else:
return True
self.boilerPlate(lock, locked)
# This is needed to make the test actually run under regrtest.py!
def test_main():
run_suite(
unittest.defaultTestLoader.loadTestsFromModule(sys.modules[__name__])
)
if __name__ == "__main__":
test_main()