Add handling for ROOT-flavored C++ notebooks that use the ".C" extension

[sjgardiner]

Recent versions of the ROOT data analysis framework offer a C++ kernel for Jupyter notebooks. The metadata saved by ROOT into these notebooks lists ".C" as the file extension rather than the more standard ".cpp"

This pull request adds handling of this file extension for the C++ language. An example ROOT C++ notebook is included that passes unit tests after the proposed code changes.

[github-actions]

Thank you for making this pull request.

Did you know? You can try it on Binder: or .

Also, the version of Jupytext developed in this PR can be installed with pip:

HATCH_BUILD_HOOKS_ENABLE=true pip install git+https://github.com/sjgardiner/jupytext.git@cpp-root

(this requires nodejs, see more at Developing Jupytext)

[mwouts]

Thank you @sjgardiner for your PR! I will have a look. Do you think we could add a mention of this in the language.md documentation file? Also, could you add the text counterpart of the notebook (it should be generated by the tests, see https://jupytext.readthedocs.io/en/latest/contributing.html#add-support-for-another-language)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.80%. Comparing base (ca731ef) to head (844f6ed).
Report is 3 commits behind head on main.

❌ Your project status has failed because the head coverage (96.76%) is below the target coverage (97.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

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  Coverage   96.80%   96.80%           
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  Files          32       32           
  Lines        5001     5003    +2     
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+ Hits         4841     4843    +2     
  Misses        160      160           

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[mwouts]

Hi @sjgardiner , I was looking into this PR.

For the avoidance of doubt, can you confirm that the correct file association for ROOT-flavored C++ notebooks is .cpp, not .C which appears in the notebook's language information ?

I will take care of fixing the CI, but we will also need to add a mention of this in language.md, and add the mirror files created by the tests (I can do that if you wish).

[mwouts]

Hi @sjgardiner , I might be able to cut a new release this week-end, could I have your confirmation on this question? I mean:

For the avoidance of doubt, can you confirm that the correct file association for ROOT-flavored C++ notebooks is .cpp, not .C which appears in the notebook's language information ?

Thank you!