feat: added a way to mark funcs as deprecated (compatible py 3.9-3.14)

[mdevolde]

feat: added a way to mark funcs as deprecated (compatible py 3.9-3.14)

Why the pull request was made

In order to introduce new interfaces without bumping the MAJOR version of the library, there was a need for a way to mark functions as deprecated, compatible from Python version 3.9 to version 3.14.

A solution would be to use the deprecated decorator from typing_extensions lib, but doesn't wan't to add a dependancy.

Summary of changes

• Added a private module containing :
  • python 3.9 - 3.12 : the new deprecated decorator (destinated for internal use).
  • python 3.13 - 1.14 : the deprecated decorator from warnings lib.
• Added an ignored rule in pyproject.toml (because the written decorator is typed, and the warnings one isn't, so using a type: ignore will trigger a mypy warning with the first one, and not with the second one).

Screenshots (if appropriate):

Not appropriate.

How has this been tested?

Tested by applying both on lib funcs.

Resources

https://docs.python.org/3/library/warnings.html#warnings.deprecated

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update (changes to documentation only)
• Refactor / code style update (non-breaking change that improves code structure or readability)
• Tests / CI improvement (adding or updating tests or CI configuration only)
• Other (please describe):

Checklist

• Followed the project's contributing guidelines.
• Updated any relevant tests.
• Updated any relevant documentation.
• Added comments to your code where necessary.
• Formatted your code, run the linters, checked types and tests.

[Copilot]

Pull request overview

This PR introduces a deprecated decorator compatible with Python 3.9-3.14 to enable marking functions as deprecated without adding external dependencies. The implementation uses the standard library warnings.deprecated for Python 3.13+ and provides a custom fallback for earlier versions.

Changes:

• Added language_tool_python/_deprecated.py module with conditional import logic for the deprecated decorator
• Updated mypy configuration in pyproject.toml to ignore unused type:ignore comments

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 7 comments.

File	Description
language_tool_python/_deprecated.py	New module providing deprecated decorator with fallback implementation for Python <3.13
pyproject.toml	Added "unused-ignore" to mypy's disable_error_code list for cross-version type annotation compatibility

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

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