1058 lines
32 KiB
Python
1058 lines
32 KiB
Python
"""Unit tests for contextlib.py, and other context managers."""
|
|
|
|
import asyncio
|
|
import io
|
|
import sys
|
|
import tempfile
|
|
import threading
|
|
import unittest
|
|
from contextlib import * # Tests __all__
|
|
from test import support
|
|
import weakref
|
|
|
|
|
|
class TestAbstractContextManager(unittest.TestCase):
|
|
|
|
def test_enter(self):
|
|
class DefaultEnter(AbstractContextManager):
|
|
def __exit__(self, *args):
|
|
super().__exit__(*args)
|
|
|
|
manager = DefaultEnter()
|
|
self.assertIs(manager.__enter__(), manager)
|
|
|
|
def test_exit_is_abstract(self):
|
|
class MissingExit(AbstractContextManager):
|
|
pass
|
|
|
|
with self.assertRaises(TypeError):
|
|
MissingExit()
|
|
|
|
def test_structural_subclassing(self):
|
|
class ManagerFromScratch:
|
|
def __enter__(self):
|
|
return self
|
|
def __exit__(self, exc_type, exc_value, traceback):
|
|
return None
|
|
|
|
self.assertTrue(issubclass(ManagerFromScratch, AbstractContextManager))
|
|
|
|
class DefaultEnter(AbstractContextManager):
|
|
def __exit__(self, *args):
|
|
super().__exit__(*args)
|
|
|
|
self.assertTrue(issubclass(DefaultEnter, AbstractContextManager))
|
|
|
|
class NoEnter(ManagerFromScratch):
|
|
__enter__ = None
|
|
|
|
self.assertFalse(issubclass(NoEnter, AbstractContextManager))
|
|
|
|
class NoExit(ManagerFromScratch):
|
|
__exit__ = None
|
|
|
|
self.assertFalse(issubclass(NoExit, AbstractContextManager))
|
|
|
|
|
|
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)
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with woohoo() as x:
|
|
self.assertEqual(state, [1])
|
|
self.assertEqual(x, 42)
|
|
state.append(x)
|
|
raise 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.assertFalse(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 as 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_except_stopiter(self):
|
|
stop_exc = StopIteration('spam')
|
|
@contextmanager
|
|
def woohoo():
|
|
yield
|
|
try:
|
|
with self.assertWarnsRegex(DeprecationWarning,
|
|
"StopIteration"):
|
|
with woohoo():
|
|
raise stop_exc
|
|
except Exception as ex:
|
|
self.assertIs(ex, stop_exc)
|
|
else:
|
|
self.fail('StopIteration was suppressed')
|
|
|
|
def test_contextmanager_except_pep479(self):
|
|
code = """\
|
|
from __future__ import generator_stop
|
|
from contextlib import contextmanager
|
|
@contextmanager
|
|
def woohoo():
|
|
yield
|
|
"""
|
|
locals = {}
|
|
exec(code, locals, locals)
|
|
woohoo = locals['woohoo']
|
|
|
|
stop_exc = StopIteration('spam')
|
|
try:
|
|
with woohoo():
|
|
raise stop_exc
|
|
except Exception as ex:
|
|
self.assertIs(ex, stop_exc)
|
|
else:
|
|
self.fail('StopIteration was suppressed')
|
|
|
|
def test_contextmanager_do_not_unchain_non_stopiteration_exceptions(self):
|
|
@contextmanager
|
|
def test_issue29692():
|
|
try:
|
|
yield
|
|
except Exception as exc:
|
|
raise RuntimeError('issue29692:Chained') from exc
|
|
try:
|
|
with test_issue29692():
|
|
raise ZeroDivisionError
|
|
except Exception as ex:
|
|
self.assertIs(type(ex), RuntimeError)
|
|
self.assertEqual(ex.args[0], 'issue29692:Chained')
|
|
self.assertIsInstance(ex.__cause__, ZeroDivisionError)
|
|
|
|
try:
|
|
with test_issue29692():
|
|
raise StopIteration('issue29692:Unchained')
|
|
except Exception as ex:
|
|
self.assertIs(type(ex), StopIteration)
|
|
self.assertEqual(ex.args[0], 'issue29692:Unchained')
|
|
self.assertIsNone(ex.__cause__)
|
|
|
|
def _create_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!"""
|
|
return baz
|
|
|
|
def test_contextmanager_attribs(self):
|
|
baz = self._create_contextmanager_attribs()
|
|
self.assertEqual(baz.__name__,'baz')
|
|
self.assertEqual(baz.foo, 'bar')
|
|
|
|
@support.requires_docstrings
|
|
def test_contextmanager_doc_attrib(self):
|
|
baz = self._create_contextmanager_attribs()
|
|
self.assertEqual(baz.__doc__, "Whee!")
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docstring_given_cm_docstring(self):
|
|
baz = self._create_contextmanager_attribs()(None)
|
|
self.assertEqual(baz.__doc__, "Whee!")
|
|
|
|
def test_keywords(self):
|
|
# Ensure no keyword arguments are inhibited
|
|
@contextmanager
|
|
def woohoo(self, func, args, kwds):
|
|
yield (self, func, args, kwds)
|
|
with woohoo(self=11, func=22, args=33, kwds=44) as target:
|
|
self.assertEqual(target, (11, 22, 33, 44))
|
|
|
|
def test_nokeepref(self):
|
|
class A:
|
|
pass
|
|
|
|
@contextmanager
|
|
def woohoo(a, b):
|
|
a = weakref.ref(a)
|
|
b = weakref.ref(b)
|
|
self.assertIsNone(a())
|
|
self.assertIsNone(b())
|
|
yield
|
|
|
|
with woohoo(A(), b=A()):
|
|
pass
|
|
|
|
def test_param_errors(self):
|
|
@contextmanager
|
|
def woohoo(a, *, b):
|
|
yield
|
|
|
|
with self.assertRaises(TypeError):
|
|
woohoo()
|
|
with self.assertRaises(TypeError):
|
|
woohoo(3, 5)
|
|
with self.assertRaises(TypeError):
|
|
woohoo(b=3)
|
|
|
|
def test_recursive(self):
|
|
depth = 0
|
|
@contextmanager
|
|
def woohoo():
|
|
nonlocal depth
|
|
before = depth
|
|
depth += 1
|
|
yield
|
|
depth -= 1
|
|
self.assertEqual(depth, before)
|
|
|
|
@woohoo()
|
|
def recursive():
|
|
if depth < 10:
|
|
recursive()
|
|
|
|
recursive()
|
|
self.assertEqual(depth, 0)
|
|
|
|
|
|
class ClosingTestCase(unittest.TestCase):
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
# Issue 19330: ensure context manager instances have good docstrings
|
|
cm_docstring = closing.__doc__
|
|
obj = closing(None)
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
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, [])
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with closing(x) as y:
|
|
self.assertEqual(x, y)
|
|
1 / 0
|
|
self.assertEqual(state, [1])
|
|
|
|
|
|
class NullcontextTestCase(unittest.TestCase):
|
|
def test_nullcontext(self):
|
|
class C:
|
|
pass
|
|
c = C()
|
|
with nullcontext(c) as c_in:
|
|
self.assertIs(c_in, c)
|
|
|
|
|
|
class FileContextTestCase(unittest.TestCase):
|
|
|
|
def testWithOpen(self):
|
|
tfn = tempfile.mktemp()
|
|
try:
|
|
f = None
|
|
with open(tfn, "w") as f:
|
|
self.assertFalse(f.closed)
|
|
f.write("Booh\n")
|
|
self.assertTrue(f.closed)
|
|
f = None
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with open(tfn, "r") as f:
|
|
self.assertFalse(f.closed)
|
|
self.assertEqual(f.read(), "Booh\n")
|
|
1 / 0
|
|
self.assertTrue(f.closed)
|
|
finally:
|
|
support.unlink(tfn)
|
|
|
|
class LockContextTestCase(unittest.TestCase):
|
|
|
|
def boilerPlate(self, lock, locked):
|
|
self.assertFalse(locked())
|
|
with lock:
|
|
self.assertTrue(locked())
|
|
self.assertFalse(locked())
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with lock:
|
|
self.assertTrue(locked())
|
|
1 / 0
|
|
self.assertFalse(locked())
|
|
|
|
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)
|
|
|
|
|
|
class mycontext(ContextDecorator):
|
|
"""Example decoration-compatible context manager for testing"""
|
|
started = False
|
|
exc = None
|
|
catch = False
|
|
|
|
def __enter__(self):
|
|
self.started = True
|
|
return self
|
|
|
|
def __exit__(self, *exc):
|
|
self.exc = exc
|
|
return self.catch
|
|
|
|
|
|
class TestContextDecorator(unittest.TestCase):
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
# Issue 19330: ensure context manager instances have good docstrings
|
|
cm_docstring = mycontext.__doc__
|
|
obj = mycontext()
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
def test_contextdecorator(self):
|
|
context = mycontext()
|
|
with context as result:
|
|
self.assertIs(result, context)
|
|
self.assertTrue(context.started)
|
|
|
|
self.assertEqual(context.exc, (None, None, None))
|
|
|
|
|
|
def test_contextdecorator_with_exception(self):
|
|
context = mycontext()
|
|
|
|
with self.assertRaisesRegex(NameError, 'foo'):
|
|
with context:
|
|
raise NameError('foo')
|
|
self.assertIsNotNone(context.exc)
|
|
self.assertIs(context.exc[0], NameError)
|
|
|
|
context = mycontext()
|
|
context.catch = True
|
|
with context:
|
|
raise NameError('foo')
|
|
self.assertIsNotNone(context.exc)
|
|
self.assertIs(context.exc[0], NameError)
|
|
|
|
|
|
def test_decorator(self):
|
|
context = mycontext()
|
|
|
|
@context
|
|
def test():
|
|
self.assertIsNone(context.exc)
|
|
self.assertTrue(context.started)
|
|
test()
|
|
self.assertEqual(context.exc, (None, None, None))
|
|
|
|
|
|
def test_decorator_with_exception(self):
|
|
context = mycontext()
|
|
|
|
@context
|
|
def test():
|
|
self.assertIsNone(context.exc)
|
|
self.assertTrue(context.started)
|
|
raise NameError('foo')
|
|
|
|
with self.assertRaisesRegex(NameError, 'foo'):
|
|
test()
|
|
self.assertIsNotNone(context.exc)
|
|
self.assertIs(context.exc[0], NameError)
|
|
|
|
|
|
def test_decorating_method(self):
|
|
context = mycontext()
|
|
|
|
class Test(object):
|
|
|
|
@context
|
|
def method(self, a, b, c=None):
|
|
self.a = a
|
|
self.b = b
|
|
self.c = c
|
|
|
|
# these tests are for argument passing when used as a decorator
|
|
test = Test()
|
|
test.method(1, 2)
|
|
self.assertEqual(test.a, 1)
|
|
self.assertEqual(test.b, 2)
|
|
self.assertEqual(test.c, None)
|
|
|
|
test = Test()
|
|
test.method('a', 'b', 'c')
|
|
self.assertEqual(test.a, 'a')
|
|
self.assertEqual(test.b, 'b')
|
|
self.assertEqual(test.c, 'c')
|
|
|
|
test = Test()
|
|
test.method(a=1, b=2)
|
|
self.assertEqual(test.a, 1)
|
|
self.assertEqual(test.b, 2)
|
|
|
|
|
|
def test_typo_enter(self):
|
|
class mycontext(ContextDecorator):
|
|
def __unter__(self):
|
|
pass
|
|
def __exit__(self, *exc):
|
|
pass
|
|
|
|
with self.assertRaises(AttributeError):
|
|
with mycontext():
|
|
pass
|
|
|
|
|
|
def test_typo_exit(self):
|
|
class mycontext(ContextDecorator):
|
|
def __enter__(self):
|
|
pass
|
|
def __uxit__(self, *exc):
|
|
pass
|
|
|
|
with self.assertRaises(AttributeError):
|
|
with mycontext():
|
|
pass
|
|
|
|
|
|
def test_contextdecorator_as_mixin(self):
|
|
class somecontext(object):
|
|
started = False
|
|
exc = None
|
|
|
|
def __enter__(self):
|
|
self.started = True
|
|
return self
|
|
|
|
def __exit__(self, *exc):
|
|
self.exc = exc
|
|
|
|
class mycontext(somecontext, ContextDecorator):
|
|
pass
|
|
|
|
context = mycontext()
|
|
@context
|
|
def test():
|
|
self.assertIsNone(context.exc)
|
|
self.assertTrue(context.started)
|
|
test()
|
|
self.assertEqual(context.exc, (None, None, None))
|
|
|
|
|
|
def test_contextmanager_as_decorator(self):
|
|
@contextmanager
|
|
def woohoo(y):
|
|
state.append(y)
|
|
yield
|
|
state.append(999)
|
|
|
|
state = []
|
|
@woohoo(1)
|
|
def test(x):
|
|
self.assertEqual(state, [1])
|
|
state.append(x)
|
|
test('something')
|
|
self.assertEqual(state, [1, 'something', 999])
|
|
|
|
# Issue #11647: Ensure the decorated function is 'reusable'
|
|
state = []
|
|
test('something else')
|
|
self.assertEqual(state, [1, 'something else', 999])
|
|
|
|
|
|
class TestBaseExitStack:
|
|
exit_stack = None
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
# Issue 19330: ensure context manager instances have good docstrings
|
|
cm_docstring = self.exit_stack.__doc__
|
|
obj = self.exit_stack()
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
def test_no_resources(self):
|
|
with self.exit_stack():
|
|
pass
|
|
|
|
def test_callback(self):
|
|
expected = [
|
|
((), {}),
|
|
((1,), {}),
|
|
((1,2), {}),
|
|
((), dict(example=1)),
|
|
((1,), dict(example=1)),
|
|
((1,2), dict(example=1)),
|
|
((1,2), dict(self=3, callback=4)),
|
|
]
|
|
result = []
|
|
def _exit(*args, **kwds):
|
|
"""Test metadata propagation"""
|
|
result.append((args, kwds))
|
|
with self.exit_stack() as stack:
|
|
for args, kwds in reversed(expected):
|
|
if args and kwds:
|
|
f = stack.callback(_exit, *args, **kwds)
|
|
elif args:
|
|
f = stack.callback(_exit, *args)
|
|
elif kwds:
|
|
f = stack.callback(_exit, **kwds)
|
|
else:
|
|
f = stack.callback(_exit)
|
|
self.assertIs(f, _exit)
|
|
for wrapper in stack._exit_callbacks:
|
|
self.assertIs(wrapper[1].__wrapped__, _exit)
|
|
self.assertNotEqual(wrapper[1].__name__, _exit.__name__)
|
|
self.assertIsNone(wrapper[1].__doc__, _exit.__doc__)
|
|
self.assertEqual(result, expected)
|
|
|
|
result = []
|
|
with self.exit_stack() as stack:
|
|
with self.assertRaises(TypeError):
|
|
stack.callback(arg=1)
|
|
with self.assertRaises(TypeError):
|
|
self.exit_stack.callback(arg=2)
|
|
stack.callback(callback=_exit, arg=3)
|
|
self.assertEqual(result, [((), {'arg': 3})])
|
|
|
|
def test_push(self):
|
|
exc_raised = ZeroDivisionError
|
|
def _expect_exc(exc_type, exc, exc_tb):
|
|
self.assertIs(exc_type, exc_raised)
|
|
def _suppress_exc(*exc_details):
|
|
return True
|
|
def _expect_ok(exc_type, exc, exc_tb):
|
|
self.assertIsNone(exc_type)
|
|
self.assertIsNone(exc)
|
|
self.assertIsNone(exc_tb)
|
|
class ExitCM(object):
|
|
def __init__(self, check_exc):
|
|
self.check_exc = check_exc
|
|
def __enter__(self):
|
|
self.fail("Should not be called!")
|
|
def __exit__(self, *exc_details):
|
|
self.check_exc(*exc_details)
|
|
with self.exit_stack() as stack:
|
|
stack.push(_expect_ok)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_ok)
|
|
cm = ExitCM(_expect_ok)
|
|
stack.push(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
stack.push(_suppress_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _suppress_exc)
|
|
cm = ExitCM(_expect_exc)
|
|
stack.push(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
stack.push(_expect_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_exc)
|
|
stack.push(_expect_exc)
|
|
self.assertIs(stack._exit_callbacks[-1][1], _expect_exc)
|
|
1/0
|
|
|
|
def test_enter_context(self):
|
|
class TestCM(object):
|
|
def __enter__(self):
|
|
result.append(1)
|
|
def __exit__(self, *exc_details):
|
|
result.append(3)
|
|
|
|
result = []
|
|
cm = TestCM()
|
|
with self.exit_stack() as stack:
|
|
@stack.callback # Registered first => cleaned up last
|
|
def _exit():
|
|
result.append(4)
|
|
self.assertIsNotNone(_exit)
|
|
stack.enter_context(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1].__self__, cm)
|
|
result.append(2)
|
|
self.assertEqual(result, [1, 2, 3, 4])
|
|
|
|
def test_close(self):
|
|
result = []
|
|
with self.exit_stack() as stack:
|
|
@stack.callback
|
|
def _exit():
|
|
result.append(1)
|
|
self.assertIsNotNone(_exit)
|
|
stack.close()
|
|
result.append(2)
|
|
self.assertEqual(result, [1, 2])
|
|
|
|
def test_pop_all(self):
|
|
result = []
|
|
with self.exit_stack() as stack:
|
|
@stack.callback
|
|
def _exit():
|
|
result.append(3)
|
|
self.assertIsNotNone(_exit)
|
|
new_stack = stack.pop_all()
|
|
result.append(1)
|
|
result.append(2)
|
|
new_stack.close()
|
|
self.assertEqual(result, [1, 2, 3])
|
|
|
|
def test_exit_raise(self):
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with self.exit_stack() as stack:
|
|
stack.push(lambda *exc: False)
|
|
1/0
|
|
|
|
def test_exit_suppress(self):
|
|
with self.exit_stack() as stack:
|
|
stack.push(lambda *exc: True)
|
|
1/0
|
|
|
|
def test_exit_exception_chaining_reference(self):
|
|
# Sanity check to make sure that ExitStack chaining matches
|
|
# actual nested with statements
|
|
class RaiseExc:
|
|
def __init__(self, exc):
|
|
self.exc = exc
|
|
def __enter__(self):
|
|
return self
|
|
def __exit__(self, *exc_details):
|
|
raise self.exc
|
|
|
|
class RaiseExcWithContext:
|
|
def __init__(self, outer, inner):
|
|
self.outer = outer
|
|
self.inner = inner
|
|
def __enter__(self):
|
|
return self
|
|
def __exit__(self, *exc_details):
|
|
try:
|
|
raise self.inner
|
|
except:
|
|
raise self.outer
|
|
|
|
class SuppressExc:
|
|
def __enter__(self):
|
|
return self
|
|
def __exit__(self, *exc_details):
|
|
type(self).saved_details = exc_details
|
|
return True
|
|
|
|
try:
|
|
with RaiseExc(IndexError):
|
|
with RaiseExcWithContext(KeyError, AttributeError):
|
|
with SuppressExc():
|
|
with RaiseExc(ValueError):
|
|
1 / 0
|
|
except IndexError as exc:
|
|
self.assertIsInstance(exc.__context__, KeyError)
|
|
self.assertIsInstance(exc.__context__.__context__, AttributeError)
|
|
# Inner exceptions were suppressed
|
|
self.assertIsNone(exc.__context__.__context__.__context__)
|
|
else:
|
|
self.fail("Expected IndexError, but no exception was raised")
|
|
# Check the inner exceptions
|
|
inner_exc = SuppressExc.saved_details[1]
|
|
self.assertIsInstance(inner_exc, ValueError)
|
|
self.assertIsInstance(inner_exc.__context__, ZeroDivisionError)
|
|
|
|
def test_exit_exception_chaining(self):
|
|
# Ensure exception chaining matches the reference behaviour
|
|
def raise_exc(exc):
|
|
raise exc
|
|
|
|
saved_details = None
|
|
def suppress_exc(*exc_details):
|
|
nonlocal saved_details
|
|
saved_details = exc_details
|
|
return True
|
|
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.callback(raise_exc, IndexError)
|
|
stack.callback(raise_exc, KeyError)
|
|
stack.callback(raise_exc, AttributeError)
|
|
stack.push(suppress_exc)
|
|
stack.callback(raise_exc, ValueError)
|
|
1 / 0
|
|
except IndexError as exc:
|
|
self.assertIsInstance(exc.__context__, KeyError)
|
|
self.assertIsInstance(exc.__context__.__context__, AttributeError)
|
|
# Inner exceptions were suppressed
|
|
self.assertIsNone(exc.__context__.__context__.__context__)
|
|
else:
|
|
self.fail("Expected IndexError, but no exception was raised")
|
|
# Check the inner exceptions
|
|
inner_exc = saved_details[1]
|
|
self.assertIsInstance(inner_exc, ValueError)
|
|
self.assertIsInstance(inner_exc.__context__, ZeroDivisionError)
|
|
|
|
def test_exit_exception_non_suppressing(self):
|
|
# http://bugs.python.org/issue19092
|
|
def raise_exc(exc):
|
|
raise exc
|
|
|
|
def suppress_exc(*exc_details):
|
|
return True
|
|
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.callback(lambda: None)
|
|
stack.callback(raise_exc, IndexError)
|
|
except Exception as exc:
|
|
self.assertIsInstance(exc, IndexError)
|
|
else:
|
|
self.fail("Expected IndexError, but no exception was raised")
|
|
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.callback(raise_exc, KeyError)
|
|
stack.push(suppress_exc)
|
|
stack.callback(raise_exc, IndexError)
|
|
except Exception as exc:
|
|
self.assertIsInstance(exc, KeyError)
|
|
else:
|
|
self.fail("Expected KeyError, but no exception was raised")
|
|
|
|
def test_exit_exception_with_correct_context(self):
|
|
# http://bugs.python.org/issue20317
|
|
@contextmanager
|
|
def gets_the_context_right(exc):
|
|
try:
|
|
yield
|
|
finally:
|
|
raise exc
|
|
|
|
exc1 = Exception(1)
|
|
exc2 = Exception(2)
|
|
exc3 = Exception(3)
|
|
exc4 = Exception(4)
|
|
|
|
# The contextmanager already fixes the context, so prior to the
|
|
# fix, ExitStack would try to fix it *again* and get into an
|
|
# infinite self-referential loop
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.enter_context(gets_the_context_right(exc4))
|
|
stack.enter_context(gets_the_context_right(exc3))
|
|
stack.enter_context(gets_the_context_right(exc2))
|
|
raise exc1
|
|
except Exception as exc:
|
|
self.assertIs(exc, exc4)
|
|
self.assertIs(exc.__context__, exc3)
|
|
self.assertIs(exc.__context__.__context__, exc2)
|
|
self.assertIs(exc.__context__.__context__.__context__, exc1)
|
|
self.assertIsNone(
|
|
exc.__context__.__context__.__context__.__context__)
|
|
|
|
def test_exit_exception_with_existing_context(self):
|
|
# Addresses a lack of test coverage discovered after checking in a
|
|
# fix for issue 20317 that still contained debugging code.
|
|
def raise_nested(inner_exc, outer_exc):
|
|
try:
|
|
raise inner_exc
|
|
finally:
|
|
raise outer_exc
|
|
exc1 = Exception(1)
|
|
exc2 = Exception(2)
|
|
exc3 = Exception(3)
|
|
exc4 = Exception(4)
|
|
exc5 = Exception(5)
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.callback(raise_nested, exc4, exc5)
|
|
stack.callback(raise_nested, exc2, exc3)
|
|
raise exc1
|
|
except Exception as exc:
|
|
self.assertIs(exc, exc5)
|
|
self.assertIs(exc.__context__, exc4)
|
|
self.assertIs(exc.__context__.__context__, exc3)
|
|
self.assertIs(exc.__context__.__context__.__context__, exc2)
|
|
self.assertIs(
|
|
exc.__context__.__context__.__context__.__context__, exc1)
|
|
self.assertIsNone(
|
|
exc.__context__.__context__.__context__.__context__.__context__)
|
|
|
|
def test_body_exception_suppress(self):
|
|
def suppress_exc(*exc_details):
|
|
return True
|
|
try:
|
|
with self.exit_stack() as stack:
|
|
stack.push(suppress_exc)
|
|
1/0
|
|
except IndexError as exc:
|
|
self.fail("Expected no exception, got IndexError")
|
|
|
|
def test_exit_exception_chaining_suppress(self):
|
|
with self.exit_stack() as stack:
|
|
stack.push(lambda *exc: True)
|
|
stack.push(lambda *exc: 1/0)
|
|
stack.push(lambda *exc: {}[1])
|
|
|
|
def test_excessive_nesting(self):
|
|
# The original implementation would die with RecursionError here
|
|
with self.exit_stack() as stack:
|
|
for i in range(10000):
|
|
stack.callback(int)
|
|
|
|
def test_instance_bypass(self):
|
|
class Example(object): pass
|
|
cm = Example()
|
|
cm.__exit__ = object()
|
|
stack = self.exit_stack()
|
|
self.assertRaises(AttributeError, stack.enter_context, cm)
|
|
stack.push(cm)
|
|
self.assertIs(stack._exit_callbacks[-1][1], cm)
|
|
|
|
def test_dont_reraise_RuntimeError(self):
|
|
# https://bugs.python.org/issue27122
|
|
class UniqueException(Exception): pass
|
|
class UniqueRuntimeError(RuntimeError): pass
|
|
|
|
@contextmanager
|
|
def second():
|
|
try:
|
|
yield 1
|
|
except Exception as exc:
|
|
raise UniqueException("new exception") from exc
|
|
|
|
@contextmanager
|
|
def first():
|
|
try:
|
|
yield 1
|
|
except Exception as exc:
|
|
raise exc
|
|
|
|
# The UniqueRuntimeError should be caught by second()'s exception
|
|
# handler which chain raised a new UniqueException.
|
|
with self.assertRaises(UniqueException) as err_ctx:
|
|
with self.exit_stack() as es_ctx:
|
|
es_ctx.enter_context(second())
|
|
es_ctx.enter_context(first())
|
|
raise UniqueRuntimeError("please no infinite loop.")
|
|
|
|
exc = err_ctx.exception
|
|
self.assertIsInstance(exc, UniqueException)
|
|
self.assertIsInstance(exc.__context__, UniqueRuntimeError)
|
|
self.assertIsNone(exc.__context__.__context__)
|
|
self.assertIsNone(exc.__context__.__cause__)
|
|
self.assertIs(exc.__cause__, exc.__context__)
|
|
|
|
|
|
class TestExitStack(TestBaseExitStack, unittest.TestCase):
|
|
exit_stack = ExitStack
|
|
|
|
|
|
class TestRedirectStream:
|
|
|
|
redirect_stream = None
|
|
orig_stream = None
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
# Issue 19330: ensure context manager instances have good docstrings
|
|
cm_docstring = self.redirect_stream.__doc__
|
|
obj = self.redirect_stream(None)
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
def test_no_redirect_in_init(self):
|
|
orig_stdout = getattr(sys, self.orig_stream)
|
|
self.redirect_stream(None)
|
|
self.assertIs(getattr(sys, self.orig_stream), orig_stdout)
|
|
|
|
def test_redirect_to_string_io(self):
|
|
f = io.StringIO()
|
|
msg = "Consider an API like help(), which prints directly to stdout"
|
|
orig_stdout = getattr(sys, self.orig_stream)
|
|
with self.redirect_stream(f):
|
|
print(msg, file=getattr(sys, self.orig_stream))
|
|
self.assertIs(getattr(sys, self.orig_stream), orig_stdout)
|
|
s = f.getvalue().strip()
|
|
self.assertEqual(s, msg)
|
|
|
|
def test_enter_result_is_target(self):
|
|
f = io.StringIO()
|
|
with self.redirect_stream(f) as enter_result:
|
|
self.assertIs(enter_result, f)
|
|
|
|
def test_cm_is_reusable(self):
|
|
f = io.StringIO()
|
|
write_to_f = self.redirect_stream(f)
|
|
orig_stdout = getattr(sys, self.orig_stream)
|
|
with write_to_f:
|
|
print("Hello", end=" ", file=getattr(sys, self.orig_stream))
|
|
with write_to_f:
|
|
print("World!", file=getattr(sys, self.orig_stream))
|
|
self.assertIs(getattr(sys, self.orig_stream), orig_stdout)
|
|
s = f.getvalue()
|
|
self.assertEqual(s, "Hello World!\n")
|
|
|
|
def test_cm_is_reentrant(self):
|
|
f = io.StringIO()
|
|
write_to_f = self.redirect_stream(f)
|
|
orig_stdout = getattr(sys, self.orig_stream)
|
|
with write_to_f:
|
|
print("Hello", end=" ", file=getattr(sys, self.orig_stream))
|
|
with write_to_f:
|
|
print("World!", file=getattr(sys, self.orig_stream))
|
|
self.assertIs(getattr(sys, self.orig_stream), orig_stdout)
|
|
s = f.getvalue()
|
|
self.assertEqual(s, "Hello World!\n")
|
|
|
|
|
|
class TestRedirectStdout(TestRedirectStream, unittest.TestCase):
|
|
|
|
redirect_stream = redirect_stdout
|
|
orig_stream = "stdout"
|
|
|
|
|
|
class TestRedirectStderr(TestRedirectStream, unittest.TestCase):
|
|
|
|
redirect_stream = redirect_stderr
|
|
orig_stream = "stderr"
|
|
|
|
|
|
class TestSuppress(unittest.TestCase):
|
|
|
|
@support.requires_docstrings
|
|
def test_instance_docs(self):
|
|
# Issue 19330: ensure context manager instances have good docstrings
|
|
cm_docstring = suppress.__doc__
|
|
obj = suppress()
|
|
self.assertEqual(obj.__doc__, cm_docstring)
|
|
|
|
def test_no_result_from_enter(self):
|
|
with suppress(ValueError) as enter_result:
|
|
self.assertIsNone(enter_result)
|
|
|
|
def test_no_exception(self):
|
|
with suppress(ValueError):
|
|
self.assertEqual(pow(2, 5), 32)
|
|
|
|
def test_exact_exception(self):
|
|
with suppress(TypeError):
|
|
len(5)
|
|
|
|
def test_exception_hierarchy(self):
|
|
with suppress(LookupError):
|
|
'Hello'[50]
|
|
|
|
def test_other_exception(self):
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with suppress(TypeError):
|
|
1/0
|
|
|
|
def test_no_args(self):
|
|
with self.assertRaises(ZeroDivisionError):
|
|
with suppress():
|
|
1/0
|
|
|
|
def test_multiple_exception_args(self):
|
|
with suppress(ZeroDivisionError, TypeError):
|
|
1/0
|
|
with suppress(ZeroDivisionError, TypeError):
|
|
len(5)
|
|
|
|
def test_cm_is_reentrant(self):
|
|
ignore_exceptions = suppress(Exception)
|
|
with ignore_exceptions:
|
|
pass
|
|
with ignore_exceptions:
|
|
len(5)
|
|
with ignore_exceptions:
|
|
with ignore_exceptions: # Check nested usage
|
|
len(5)
|
|
outer_continued = True
|
|
1/0
|
|
self.assertTrue(outer_continued)
|
|
|
|
if __name__ == "__main__":
|
|
unittest.main()
|