Fix/type action restriction

[PabloLION]

What does this PR do?

Fix #685
Now in add_argument, passing action=None behaves like call without argument action.

parser.add_argument(
    "--string",
    type=str,
    action=None,
    default="default",
    help="example string",
)

Before submitting

• Did you read the contributing guideline?
• Did you update the documentation? (readme and public docstrings)
• Did you write unit tests such that there is 100% coverage on related code? (required for bug fixes and new features)
• Did you verify that new and existing tests pass locally?
• Did you make sure that all changes preserve backward compatibility?
• Did you update the CHANGELOG? (not for typos, docs, test updates, or minor internal changes/refactors)

[PabloLION]

Additional info

When creating remote branch, the git hook fired and I got this

mypy................................................................................Failed
- hook id: mypy
- duration: 0.98s
- exit code: 1

jsonargparse/_stubs_resolver.py:51: error: No overload variant of "Assign" matches argument types "list[Name | Attribute | Subscript]", "expr | None", "list[Never]", "int", "int"  [call-overload]
jsonargparse/_stubs_resolver.py:51: note: Possible overload variants:
jsonargparse/_stubs_resolver.py:51: note:     def Assign(self, targets: list[expr], value: expr, type_comment: str | None = ..., *, lineno: int = ..., col_offset: int = ..., end_lineno: int | None = ..., end_col_offset: int | None = ...) -> Assign
jsonargparse/_stubs_resolver.py:51: note:     def Assign(self, targets: list[expr] = ..., *, value: expr, type_comment: str | None = ..., lineno: int = ..., col_offset: int = ..., end_lineno: int | None = ..., end_col_offset: int | None = ...) -> Assign
jsonargparse/_stubs_resolver.py:53: error: Unused "type: ignore" comment  [unused-ignore]
jsonargparse/_stubs_resolver.py:54: error: Unused "type: ignore" comment  [unused-ignore]
Found 3 errors in 1 file (checked 3 source files)

Since I didn't edit these files, I used --no-verify.

Also, I didn't have mypy/ruff installed (which made. Maybe we can consider adding them to the contributing guideline? I saw them in pyproject.toml but I could format my code :-( without them.

[PabloLION]

not sure where to put the test:

• test_typehints (I added here: the edited file is _typehints.py, and the feature is also about a valid type with a None action)
• test_actions (the feature is about action)
• test_core (the feature is about add_argument)
• test_formatters (do we need to test how help changes? like adding "test_help_type_and_no_action")

[PabloLION]

Also I find another problem: we pass in choices=None it works differently here

jsonargparse/jsonargparse/_core.py

Line 142 in c3d3df7

if "choices" in kwargs and not isinstance(kwargs["choices"], (list, tuple)):

Should I create another PR on this?

[mauvilsa]

Issue #685 also mentioned the case type=None so I was expecting a test for this.

[mauvilsa]

Also I find another problem: we pass in choices=None it works differently here

jsonargparse/jsonargparse/_core.py

Line 142 in c3d3df7

if "choices" in kwargs and not isinstance(kwargs["choices"], (list, tuple)):

Should I create another PR on this?

How does it work differently? I think it could be part of this pull request.

[mauvilsa]

When creating remote branch, the git hook fired and I got this

mypy................................................................................Failed

I see. I think I need to specify in the pre-commit config which python version to run mypy with. No problem that you skipped it.

Also, I didn't have mypy/ruff installed (which made. Maybe we can consider adding them to the contributing guideline? I saw them in pyproject.toml but I could format my code :-( without them.

mypy/ruff don't need to be installed. It is pre-commit the one that installs them in a separate environment. If you want to only run ruff do

pre-commit run -a ruff

to only run mypy, do

pre-commit run -a --hook-stage pre-push mypy

[PabloLION]

Also I find another problem: we pass in choices=None it works differently here

jsonargparse/jsonargparse/_core.py

Line 142 in c3d3df7

if "choices" in kwargs and not isinstance(kwargs["choices"], (list, tuple)):

Should I create another PR on this?

How does it work differently? I think it could be part of this pull request.

When action is not None, passing choices=None, there will be similar problem with type=None.
But I have more doubts about choices: I'm creating a parser with dataclass where some fields are Enum type, and only a part of the Enum should be used. (Enum CLI args are matched by the name instead of value.)
In this case, jsonargparse will check if the parsed value is in choices, not the user input. However, the help test is only showing the parsed option, not what user should input.

I meant to create a new issue but I have not read the document nor have I tested it yet. Do you think this worths a shot?

[PabloLION]

mypy/ruff don't need to be installed

Without them, I cannot format the code effectively. The suggestion was to add a part to mentioning the toolkit we are using in this project for more consistent code style.

[mauvilsa]

Please add an entry to the changelog. After that, this would be good to merge.

With type=None and action=None, there's no problem with the old code. Should we still add the test?

Okay, fine. Then lets leave it like that.

When action is not None, passing choices=None, there will be similar problem with type=None.
But I have more doubts about choices: I'm creating a parser with dataclass where some fields are Enum type, and only a part of the Enum should be used. (Enum CLI args are matched by the name instead of value.)
In this case, jsonargparse will check if the parsed value is in choices, not the user input. However, the help test is only showing the parsed option, not what user should input.

I meant to create a new issue but I have not read the document nor have I tested it yet. Do you think this worths a shot?

Okay, it does sound like this needs a specific issue to address.

[mauvilsa]

mypy/ruff don't need to be installed

Without them, I cannot format the code effectively. The suggestion was to add a part to mentioning the toolkit we are using in this project for more consistent code style.

Can you explain what you mean by "I cannot format the code effectively"? The code will be automatically formatted when pre-commit runs. And even if pre-commit is skipped, a github action will format it.

[PabloLION]

I added the change log and I think it's ready to merge.

Can you explain what you mean by "I cannot format the code effectively"? The code will be automatically formatted when pre-commit runs. And even if pre-commit is skipped, a github action will format it.

I wanted to say that I avoided formatting the code intentionally because my line length was set to 80 instead of 120 on my local environment because I didn't know about the GitHub action. And Pylance was reporting this everywhere

"_ActionPrintConfig" is private and used outside of the module in which it is declared (Pylance) 
[reportPrivateUsage](https://github.com/microsoft/pyright/blob/main/docs/configuration.md#reportPrivateUsage)

And about the Union type deprecation "This type is deprecated as of Python 3.10" etc. I guess our env was very different and I didn't change my python interpreter version (I'm exactly suffering for "mac313").

Anyway, thanks for your patience and guidance in this PR. I'll create another issue on the "choices" args.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (c3d3df7) to head (0fbc4c4).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #687   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           22        22           
  Lines         6688      6688           
=========================================
  Hits          6688      6688           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[mauvilsa]

Thank you for contributing!

[mauvilsa]

Can you explain what you mean by "I cannot format the code effectively"? The code will be automatically formatted when pre-commit runs. And even if pre-commit is skipped, a github action will format it.

I wanted to say that I avoided formatting the code intentionally because my line length was set to 80 instead of 120 on my local environment because I didn't know about the GitHub action. And Pylance was reporting this everywhere

"_ActionPrintConfig" is private and used outside of the module in which it is declared (Pylance) 
[reportPrivateUsage](https://github.com/microsoft/pyright/blob/main/docs/configuration.md#reportPrivateUsage)

And about the Union type deprecation "This type is deprecated as of Python 3.10" etc. I guess our env was very different and I didn't change my python interpreter version (I'm exactly suffering for "mac313").

Thanks for the info! I will do some changes and probably ping you for review.