Extensions

Extensions provide concrete implementations of actions as handlers. All extensions listed here are maintained in the FineCode repository under extensions/.

To use an extension, add its handler to an action in your pyproject.toml or use a preset that includes it. The extension package is installed automatically into the handler's virtual environment by prepare-envs.

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Linting

fine_python_ruff

Linting and formatting via Ruff.

Handler	Action	Description
fine_python_ruff.RuffLintFilesHandler	lint_files	Lint Python files with Ruff
fine_python_ruff.RuffFormatFilesHandler	format_files	Format Python files with Ruff formatter

Example config:

[[tool.finecode.action_handler]]
source = "fine_python_ruff.RuffLintFilesHandler"
config.extend_select = ["B", "I"]
config.line_length = 88
config.target_version = "py311"

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fine_python_flake8

Linting via Flake8.

Handler	Action	Description
fine_python_flake8.Flake8LintFilesHandler	lint_files	Lint Python files with Flake8

Example config:

[[tool.finecode.action_handler]]
source = "fine_python_flake8.Flake8LintFilesHandler"
config.max_line_length = 88
config.extend_ignore = ["E203", "E501"]
config.select = []   # disable all standard rules (use only custom rules)

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fine_python_mypy

Type checking via Mypy.

Handler	Action	Description
fine_python_mypy.MypyLintHandler	lint / lint_files	Type-check Python files

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fine_python_import_linter

Architecture validation via import-linter.

Handler	Action	Description
fine_python_import_linter.ImportLinterHandler	lint	Validate import contracts

Reads contract definitions from [tool.importlinter] in pyproject.toml.

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fine_python_pyrefly

Type checking and LSP integration via Pyrefly.

Handler	Action	Description
fine_python_pyrefly.PyreflyLintFilesHandler	lint_files	Type-check with Pyrefly

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fine_python_ast

AST-based analysis for Python source files.

Handler	Action	Description
fine_python_ast.AstHandler	Various	AST traversal and analysis

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Formatting

fine_python_black

Code formatting via Black.

Handler	Action	Description
fine_python_black.BlackFormatFilesHandler	format_files	Format Python files with Black

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fine_python_isort

Import sorting via isort.

Handler	Action	Description
fine_python_isort.IsortFormatFilesHandler	format_files	Sort Python imports

Example config (compatible with Ruff formatter / Black):

[[tool.finecode.action_handler]]
source = "fine_python_isort.IsortFormatFilesHandler"
config.multi_line_output = 3
config.include_trailing_comma = true
config.line_length = 88
config.split_on_trailing_comma = true

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Package & environment management

fine_python_pip

Environment management via pip.

Handler	Action	Description
fine_python_pip.PipInstallDepsInEnvHandler	install_deps_in_env	Install dependencies with pip

Example config:

[[tool.finecode.action_handler]]
source = "fine_python_pip.PipInstallDepsInEnvHandler"
config.editable_mode = "compat"   # "compat", "strict", or default

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fine_python_virtualenv

Virtual environment creation.

Handler	Action	Description
fine_python_virtualenv.VirtualenvPrepareEnvHandler	prepare_envs	Create virtualenvs

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fine_python_setuptools_scm

Version management via setuptools-scm.

Handler	Action	Description
fine_python_setuptools_scm.GetSrcArtifactVersionSetuptoolsScmHandler	get_src_artifact_version	Read version from VCS tags

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Analysis

fine_python_module_exports

Analyzes and validates Python module exports.

Handler	Action	Description
fine_python_module_exports.*	Various	Validate __all__ and public API

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fine_python_package_info

Reads package metadata from pyproject.toml.

Handler	Action	Description
fine_python_package_info.*	Various	Provide package name, version, files