diff options
| -rw-r--r-- | Lib/test/test_with.py | 30 | ||||
| -rw-r--r-- | Misc/NEWS | 3 | ||||
| -rw-r--r-- | Python/ceval.c | 19 |
3 files changed, 46 insertions, 6 deletions
diff --git a/Lib/test/test_with.py b/Lib/test/test_with.py index 3007e5a..bfeb06b 100644 --- a/Lib/test/test_with.py +++ b/Lib/test/test_with.py @@ -503,6 +503,36 @@ class ExceptionalTestCase(unittest.TestCase, ContextmanagerAssertionMixin): self.assertRaises(GeneratorExit, shouldThrow) + def testErrorsInBool(self): + # issue4589: __exit__ return code may raise an exception + # when looking at its truth value. + + class cm(object): + def __init__(self, bool_conversion): + class Bool: + def __nonzero__(self): + return bool_conversion() + self.exit_result = Bool() + def __enter__(self): + return 3 + def __exit__(self, a, b, c): + return self.exit_result + + def trueAsBool(): + with cm(lambda: True): + self.fail("Should NOT see this") + trueAsBool() + + def falseAsBool(): + with cm(lambda: False): + self.fail("Should raise") + self.assertRaises(AssertionError, falseAsBool) + + def failAsBool(): + with cm(lambda: 1//0): + self.fail("Should NOT see this") + self.assertRaises(ZeroDivisionError, failAsBool) + class NonLocalFlowControlTestCase(unittest.TestCase): @@ -12,6 +12,9 @@ What's New in Python 2.7 alpha 1 Core and Builtins ----------------- +- Issue #4597: Fixed exception handling when the __exit__ function of a + context manager returns a value that cannot be converted to a bool. + - Issue #4597: Fixed several opcodes that weren't always propagating exceptions. diff --git a/Python/ceval.c b/Python/ceval.c index 0a1d86a..bd35185 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -2349,11 +2349,20 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag) /* XXX Not the fastest way to call it... */ x = PyObject_CallFunctionObjArgs(exit_func, u, v, w, NULL); - if (x == NULL) { - Py_DECREF(exit_func); + Py_DECREF(exit_func); + if (x == NULL) break; /* Go to error exit */ - } - if (u != Py_None && PyObject_IsTrue(x)) { + + if (u != Py_None) + err = PyObject_IsTrue(x); + else + err = 0; + Py_DECREF(x); + + if (err < 0) + break; /* Go to error exit */ + else if (err > 0) { + err = 0; /* There was an exception and a true return */ STACKADJ(-2); Py_INCREF(Py_None); @@ -2365,8 +2374,6 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag) /* The stack was rearranged to remove EXIT above. Let END_FINALLY do its thing */ } - Py_DECREF(x); - Py_DECREF(exit_func); PREDICT(END_FINALLY); break; } |