bpo-43950: Print columns in tracebacks (PEP 657)

[ammaraskar]

This pull request implements the relevant bits in traceback printing to utilize the new co_positions and PyCode_Addr2... APIs to print carets for column locations.

All the internal structures, and data representation are subjected to change in future PRs as we add optimizations.

https://bugs.python.org/issue43950

[pablogsal]

@ammaraskar Ground control to major tom, commencing countdown engines on

Rebase time!

[pablogsal]

@pablogsal would you mind cleaning up the byte_to_character_offset_in_line function here.

Yeah, I will do that. Could you address first @isidentical feedback?

[pablogsal]

@ammaraskar Can you open the prs for the follow-ups?

#26958 (comment)

[ammaraskar]

#27023 for the config change, working on the traceback.py refactor + a bpo issue.

[ammaraskar]

https://bugs.python.org/issue44569 for the traceback.py change, PR for it coming soon.

[graingert]

this doesn't seem correct -

Python 3.11.0 | packaged by conda-forge | (main, Oct 25 2022, 06:18:27) [GCC 10.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import traceback
>>> traceback.walk_stack(None)
<generator object walk_stack at 0x7f308f4c4700>
>>> list(traceback.walk_stack(None))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/graingert/anaconda3/envs/dask-distributed-311/lib/python3.11/traceback.py", line 332, in walk_stack
f = sys._getframe().f_back.f_back.f_back.f_back
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'f_back'
>>> 

[pablogsal]

Please, don't comment on merged pull requests because they are not monitored and you risk no one looking at your comment. Always open a new issue :)