gh-135227: argparse: Use help as default description in add_parser

[Sonu0305]

Fixes #135227

• Issue: argparse._SubParsersAction.add_parser should default to description matching help #135227

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[StanFromIreland]

This will need a blurb entry and test for the new behavior.

[Sonu0305]

This will need a blurb entry and test for the new behavior.

Thanks.

edit: typo

[StanFromIreland]

Please stop repeatedly force pushing, it confuses GitHub.

[Sonu0305]

Please stop repeatedly force pushing, it confuses GitHub.

Sorry.

[serhiy-storchaka]

What is the way to restore the current behavior? I.e. to create a parser without description?

[brianschubert]

@Sonu0305 it's generally best to avoid force pushing once you've received feedback, since it makes it harder for reviewers to see what changed. PRs are squash merged anyway

[Sonu0305]

@Sonu0305 it's generally best to avoid force pushing once you've received feedback, since it makes it harder for reviewers to see what changed. PRs are squash merged anyway

Sorry, I pushed a commit with wrong changes, hence I decided to force push, I will surely avoid this and keep in mind.
Sorry & Thanks again.

[Sonu0305]

What is the way to restore the current behavior? I.e. to create a parser without description?

New changes, help in a way, where description is set to default only when help is not None, and the user does not provide description explicitly.
Let me know if this is the expected behaviour,
Thank You.

[serhiy-storchaka]

What if the user wants help but no description?

[Sonu0305]

What if the user wants help but no description?

The user can set description to None.
I can add tests for this case as well.
And if required, we can document it as well.

[serhiy-storchaka]

Yes, please add a test. Add also tests for either help or description are SUPPRESS.

This needs also documentation, and it is difficult to find a good place for it, because add_parser() is not documented separately, but as a part of add_subparsers() which has its own parameters. The best place is perhaps somewhere near a paragraph that starts with "Similarly, when a help message is requested from a subparser, only the help for that particular parser will be printed." You will need also to update the following example. Be concise. Add a versionchanged directive after the example. These are just tips, you may find something better. Rewrite the existing text if it makes the result better.

cc @savannahostrowski

[github-actions]

This PR is stale because it has been open for 30 days with no activity.

[savannahostrowski]

I'm going to close this as stale, since there's unaddressed feedback and this has been open for quite sometime. Happy to revisit if feedback is addressed.