pnl supports two config file formats: a standalone YAML file or an inline section inside pyproject.toml.

Config File Discovery¶

When you run pnl check without --config, the tool searches upward from the current working directory for one of:

• .python-naming-linter.yaml
• pyproject.toml (containing a [tool.python-naming-linter] section)

The first matching file is used, and its parent directory becomes the project root.

To use a specific config file, pass it explicitly:

pnl check --config path/to/config.yaml

YAML Format¶

Create .python-naming-linter.yaml in your project root:

rules:
  - name: bool-method-prefix
    type: function
    filter: { return_type: bool }
    naming: { prefix: [is_, has_, should_] }

apply:
  - name: all
    rules: [bool-method-prefix]
    modules: "**"

pyproject.toml Format¶

You can embed the same configuration inside pyproject.toml using the [tool.python-naming-linter] namespace:

[[tool.python-naming-linter.rules]]
name = "bool-method-prefix"
type = "function"

[tool.python-naming-linter.rules.filter]
return_type = "bool"

[tool.python-naming-linter.rules.naming]
prefix = ["is_", "has_", "should_"]

[[tool.python-naming-linter.apply]]
name = "all"
rules = ["bool-method-prefix"]
modules = "**"

Both formats are equivalent — use whichever fits your project's conventions.

Top-Level Keys¶

include / exclude¶

Control which files are scanned:

include:
  - src
exclude:
  - src/generated/**

Behavior:

• Neither — all .py files under the project root are scanned.
• include only — only files matching the given paths are scanned.
• exclude only — all files except those matching the given paths are scanned.
• Both — include is applied first, then exclude filters within that result.