Bug report
When notes on an exception cannot be shown because the repr and str raise exceptions, a <note str() failed> message is shown instead. In the case where exception.__notes__ is not a sequence and cannot be shown, a <__notes__ repr() failed> is shown. In the second case, the message does not include a trailing newline.
__notes__ is a list containing a broken "note" - output includes a newline:
class A:
def __repr__(self):
raise Exception()
e = Exception()
e.__notes__ = [A()] # !!!
raise euser@host $ ./repro.py
Traceback (most recent call last):
File "./repro.py", line 8, in <module>
raise e
Exception
<note str() failed>
user@host $
__notes__ is just a single broken "note" - output does not include a newline:
class A:
def __repr__(self):
raise Exception()
e = Exception()
e.__notes__ = A() # !!!
raise euser@host $ ./repro.py
Traceback (most recent call last):
File "./repro.py", line 8, in <module>
raise e
Exception
<__notes__ repr() failed>user@host $
Additionally, when __notes__ is a string/bytes, the contents are expoded over multiple lines because of an isinstance(__notes__, Sequence) check.
String:
e = Exception()
e.__notes__ = "a note"
raise e
user@host $ ./repro.py
Traceback (most recent call last):
File "./repro.py", line 8, in <module>
raise e
Exception
a
n
o
t
e
user@host $
Bytes:
e = Exception()
e.__notes__ = b"a note"
raise e
user@host $ ./repro.py
Traceback (most recent call last):
File "./repro.py", line 8, in <module>
raise e
Exception
97
32
110
111
116
101
user@host $
Even though the above are all edge cases, since there are some checks that handle these cases already, it makes sense to handle them more gracefully.
Your environment
- CPython versions tested on: 3.12.0a7+
- Operating system and architecture: macOS Mojave (x86)
Linked PRs
Bug report
When notes on an exception cannot be shown because the
reprandstrraise exceptions, a<note str() failed>message is shown instead. In the case whereexception.__notes__is not a sequence and cannot be shown, a<__notes__ repr() failed>is shown. In the second case, the message does not include a trailing newline.__notes__is a list containing a broken "note" - output includes a newline:__notes__is just a single broken "note" - output does not include a newline:Additionally, when
__notes__is a string/bytes, the contents are expoded over multiple lines because of anisinstance(__notes__, Sequence)check.String:
Bytes:
Even though the above are all edge cases, since there are some checks that handle these cases already, it makes sense to handle them more gracefully.
Your environment
Linked PRs
Exception.__notes__are displayed #103897