Fixes #3084 — Restore optional value behavior for options with flag_value

[trippinganymess]

This PR:

• Corrects Option.init logic to ensure options using flag_value and is_flag=False work as documented, accepting just the flag and using the flag_value as the option's value.
• Adds comprehensive tests in tests/test_optional_value_bug.py that fail before and pass after this fix, demonstrating the bug and its resolution.
• Updates code documentation with a new .. versionchanged:: note, and adds a changelog entry summarizing the change.

This restores the intended and documented API behavior, aligning Click’s implementation with user expectations and preventing regressions in downstream projects

[davidism]

Don't create a completely new file to test one bug fix. All that's needed is probably one new parametrization of an existing test.

Also, the docstrings, comments, and verbosity of the tests is not really helping at all.

[davidism]

This version is wrong.

[davidism]

This change comment is way too verbose. "Restore optional value behavior when flag_value is set."

[davidism]

Follow the style in the rest of the changelog. Don't add a tag prefix, use the correct reference, add this to a new section rather than an already released version.

Also, the PR title, commit message, docstring, and this line are all different wordings of the same fix. Be consistent.

[davidism]

I appreciate that you submitted a fix for this. However, your use of AI really detracted from the quality of the PR. Please avoid using AI, or at least carefully review the results and compare them to the project style before submitting.

The initial PR description is also a wordy mess that AI tends to produce.

"fixes #..." should be in the PR description, not a tag in the title.

You haven't configured git correctly, so your commits aren't linked to your GitHub account.

The commit message, PR title, changelog entry, and docstring changelog entry are all worded differently.

[trippinganymess]

I will try to be more careful next time, Thank you so much for the review

[davidism]

This needs to be rebased onto stable instead of main as well.

[trippinganymess]

Hi, I think I have made all the relevant changes, I am sorry for being negligence before. It was my first contribution to open source I went on chasing for a quick win. please lemme know if there is anything still wrong I will try to make it right.

Thank you!!