diff options
| -rw-r--r-- | Lib/contextlib.py | 12 | ||||
| -rw-r--r-- | Lib/test/test_contextlib.py | 23 | ||||
| -rw-r--r-- | Misc/NEWS | 3 |
3 files changed, 32 insertions, 6 deletions
diff --git a/Lib/contextlib.py b/Lib/contextlib.py index e91cf46..5e47054 100644 --- a/Lib/contextlib.py +++ b/Lib/contextlib.py @@ -88,7 +88,7 @@ class _GeneratorContextManager(ContextDecorator, AbstractContextManager): try: next(self.gen) except StopIteration: - return + return False else: raise RuntimeError("generator didn't stop") else: @@ -110,7 +110,7 @@ class _GeneratorContextManager(ContextDecorator, AbstractContextManager): # Likewise, avoid suppressing if a StopIteration exception # was passed to throw() and later wrapped into a RuntimeError # (see PEP 479). - if exc.__cause__ is value: + if type is StopIteration and exc.__cause__ is value: return False raise except: @@ -121,10 +121,10 @@ class _GeneratorContextManager(ContextDecorator, AbstractContextManager): # fixes the impedance mismatch between the throw() protocol # and the __exit__() protocol. # - if sys.exc_info()[1] is not value: - raise - else: - raise RuntimeError("generator didn't stop after throw()") + if sys.exc_info()[1] is value: + return False + raise + raise RuntimeError("generator didn't stop after throw()") def contextmanager(func): diff --git a/Lib/test/test_contextlib.py b/Lib/test/test_contextlib.py index c04c804..b1a467d 100644 --- a/Lib/test/test_contextlib.py +++ b/Lib/test/test_contextlib.py @@ -152,6 +152,29 @@ def woohoo(): 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): @@ -306,6 +306,9 @@ Extension Modules Library ------- +- bpo-29692: Fixed arbitrary unchaining of RuntimeError exceptions in + contextlib.contextmanager. + Patch by Siddharth Velankar. - bpo-26187: Test that sqlite3 trace callback is not called multiple times when schema is changing. Indirectly fixed by switching to |