diff --git a/Lib/test/test_traceback.py b/Lib/test/test_traceback.py index e0ef9e03f1ff9f2..61eb0a7ef93d7f5 100644 --- a/Lib/test/test_traceback.py +++ b/Lib/test/test_traceback.py @@ -1654,6 +1654,21 @@ def __repr__(self): err_msg = "b'please do not show me as numbers'" self.assertEqual(self.get_report(e), vanilla + err_msg + '\n') + # an exception with a broken __getattr__ raising a non expected error + class BrokenException(Exception): + broken = False + def __getattr__(self, name): + if self.broken: + raise ValueError(f'no {name}') + raise AttributeError(name) + + e = BrokenException(123) + vanilla = self.get_report(e) + e.broken = True + self.assertEqual( + self.get_report(e), + vanilla + "Ignored error getting __notes__: ValueError('no __notes__')\n") + def test_exception_with_multiple_notes(self): for e in [ValueError(42), SyntaxError('bad syntax')]: with self.subTest(e=e): diff --git a/Lib/traceback.py b/Lib/traceback.py index f61d5db0621ab5b..b210169117bffb3 100644 --- a/Lib/traceback.py +++ b/Lib/traceback.py @@ -738,7 +738,11 @@ def __init__(self, exc_type, exc_value, exc_traceback, *, limit=None, # Capture now to permit freeing resources: only complication is in the # unofficial API _format_final_exc_line self._str = _safe_string(exc_value, 'exception') - self.__notes__ = getattr(exc_value, '__notes__', None) + try: + self.__notes__ = getattr(exc_value, '__notes__', None) + except Exception as e: + self.__notes__ = [ + f'Ignored error getting __notes__: {_safe_string(e, "__notes__", repr)}'] if exc_type and issubclass(exc_type, SyntaxError): # Handle SyntaxError's specially diff --git a/Misc/NEWS.d/next/Library/2023-12-21-14-55-06.gh-issue-113358.nRkiSL.rst b/Misc/NEWS.d/next/Library/2023-12-21-14-55-06.gh-issue-113358.nRkiSL.rst new file mode 100644 index 000000000000000..76416553a231a0d --- /dev/null +++ b/Misc/NEWS.d/next/Library/2023-12-21-14-55-06.gh-issue-113358.nRkiSL.rst @@ -0,0 +1 @@ +Fix rendering tracebacks with exceptions with a broken __getattr__ diff --git a/Python/pythonrun.c b/Python/pythonrun.c index f4c5d39c59b166a..c93d591a44fef92 100644 --- a/Python/pythonrun.c +++ b/Python/pythonrun.c @@ -1164,6 +1164,35 @@ print_exception_notes(struct exception_print_context *ctx, PyObject *notes) return -1; } +static int +get_exception_notes(struct exception_print_context *ctx, PyObject *value, PyObject **notes) { + PyObject *type; + PyObject *errvalue; + PyObject *tback; + PyObject *note = NULL; + + if (_PyObject_LookupAttr(value, &_Py_ID(__notes__), notes) < 0) { + PyErr_Fetch(&type, &errvalue, &tback); + PyErr_Clear(); + *notes = PyList_New(1); + if (!*notes) { + goto error; + } + note = PyUnicode_FromFormat("Ignored error getting __notes__: %R", errvalue); + if (!note) { + goto error; + } + if (PyList_SetItem(*notes, 0, note) < 0) { + goto error; + } + } + + return 0; +error: + Py_XDECREF(note); + return -1; +} + static int print_exception(struct exception_print_context *ctx, PyObject *value) { @@ -1183,7 +1212,7 @@ print_exception(struct exception_print_context *ctx, PyObject *value) /* grab the type and notes now because value can change below */ PyObject *type = (PyObject *) Py_TYPE(value); - if (_PyObject_LookupAttr(value, &_Py_ID(__notes__), ¬es) < 0) { + if (get_exception_notes(ctx, value, ¬es) < 0) { goto error; }