Tadhg McDonald-Jensen <tadhgmis...@gmail.com> added the comment:
This is doable, the feature that decides which line is shown in the traceback is the `lnotab` structure in the relevant code object, the structure is described here (https://github.com/python/cpython/blob/3.8/Objects/lnotab_notes.txt) and it supports negative line offsets so it'd be possible to get the with statement closing statements to backup the line numbers to point to the with statement in question. I have attached a python script which actually achieves this. `correct_with_cleanup_traceback` when passed a function changes the relevant line numbers so the traceback actually point to the with statement when the error is thrown in the __exit__, most of the relevant work is just dealing with the weird format of lnotab. This is the error thrown by the test script, it has 2 cascading failures in exit so that I could confirm it worked for nested withs and it absolutely points to the relevant with statement as I have highlighted on the traceback, Traceback (most recent call last): File "/Users/tadhgmcdonald-jensen/Documents/test.py", line 71, in my_test >> with Test(True) as will_fail_first: <<<--------- HERE File "/Users/tadhgmcdonald-jensen/Documents/test.py", line 67, in __exit__ raise Exception("error in exit") Exception: error in exit During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/Users/tadhgmcdonald-jensen/Documents/test.py", line 78, in <module> my_test() File "/Users/tadhgmcdonald-jensen/Documents/test.py", line 70, in my_test >> with Test(True) as fail_during_handling: <<<--------- HERE File "/Users/tadhgmcdonald-jensen/Documents/test.py", line 67, in __exit__ raise Exception("error in exit") Exception: error in exit ---------- Added file: https://bugs.python.org/file49322/with_traceback_monkeypatch.py _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue25538> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
