feat(commit): add '--allow-empty' flag to commit command

[AdrianDC]

Description

feat(commit): add '--allow-empty' flag to commit command

• Reworked over fix(commit): resolve 'always_signoff' configuration and '-s' CLI issues #1206 (commits follow-up)
• Reimplementation of Feature/allow empty commit #592, authorship preserved

Checklist

• Add test cases to all the changes you introduce
• Run ./scripts/format and ./scripts/test locally to ensure this change passes linter check and test
• Test the changes on the local machine manually
• Update the documentation for the changes

Expected behavior

Allow to invoke cz and create a commit without any change in it

Steps to Test This Pull Request

git cz c --allow-empty

Additional context

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.58%. Comparing base (120d514) to head (a442d70).
Report is 508 commits behind head on master.

Additional details and impacted files

@@ Coverage Diff @@## master #1217 +/- ##
==========================================
+ Coverage 97.33% 97.58% +0.24% 
==========================================
Files 42 55 +13 Lines 2104 2608 +504 ==========================================
+ Hits 2048 2545 +497 - Misses 56 63 +7 

Flag	Coverage Δ
unittests	97.58% <100.00%> (+0.24%)	⬆️

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[Lee-W]

Hi, thanks for contributing! would like to know why do we want --alow-empty. I thought we already have -- --allow-empty

[AdrianDC]

Coverage fixed 👍.

Lee-W, apart from regular usage, it's because the staging area checks fail :

 $ cz c --allow-empty
-Invalid commitizen arguments were found: `--allow-empty`. Please use -- separator for extra git args
$ cz c -- --allow-empty
-No files added to staging!
# =======================
$ pipx uninstall commitizen; pipx install .
uninstalled commitizen! ✨ 🌟 ✨
installed package commitizen 3.29.0, installed using Python 3.12.3
These apps are now globally available
- cz
- git-cz
done! ✨ 🌟 ✨
# =======================
$ cz c --allow-empty
? Select the type of change you are committing feat: A new feature. Correlates with MINOR in SemVer
? What is the scope of this change? (class or file name): (press [enter] to skip)
test
? Write a short and imperative summary of the code changes: (lower case and no period)
test
? Provide additional contextual information about the code changes: (press [enter] to skip)
? Is this a BREAKING CHANGE? Correlates with MAJOR in SemVer No
? Footer. Information about Breaking Changes and reference issues that this commit closes: (press [enter] to skip)
feat(test): test
[master 6b9618c5] feat(test): test
+Commit successful!

[AdrianDC]

As discussed, I redid it all into -- --allow-empty support + implemented matching tests 👍.

Tested locally with cz c, cz c -- --allow-empty and cz c -s --allow-empty

[Lee-W]

Looks like part of the code is also used in #1206. let's merge #1206 first and rebase that into this one and then I'll take a final review.

[AdrianDC]

Rebased, ready to roll after 1206 👍

[Lee-W]

1206 merged 🙌

[AdrianDC]

👍