The python PEG parser generator doesn't allow f-strings anymore in actions

[pablogsal]

After the changes in 3.12 to the f-string formalisation, the PEG parser doesn't recognise the new tokens.

Linked PRs

• gh-125588: Teach the python PEG generator the new f-string tokens #125589
• gh-125588: Allow to regenerate the parser with Python < 3.12 #127969

[db3l]

Just ran into this today when trying to test a clean build of main on my buildbot. My buildbot has a system python of 3.11, but with this change, it needs to be 3.12+ otherwise there's an exception on non-existent FSTRING_* attributes in the token module. The issue hasn't yet presented itself on any of the regular builder builds, I guess due to re-generation not usually being necessary, but presumably it will the next time the grammar is touched.

It appears 3.10+ is the current minimum enforced by find_python.bat under Windows (and I believe configure under Linux). I can fix things by adding a default "None" parameter to the new getattr() calls (together with the existing "if not" checks) but am unsure if this would still produce the right final output, or if the minimum system python version just needs to be bumped.

[pablogsal]

Just ran into this today when trying to test a clean build of main on my buildbot. My buildbot has a system python of 3.11, but with this change, it needs to be 3.12+ otherwise there's an exception on non-existent FSTRING_* attributes in the token module. The issue hasn't yet presented itself on any of the regular builder builds, I guess due to re-generation not usually being necessary, but presumably it will the next time the grammar is touched.

I think that has been an oversight in #125589 I will fix it soon