Exclude dependency and build folders from a hygiene scan

Direct answer

An exclusion list is most useful when it is short, visible, and applied to path components rather than a substring. This example ignores a path only when one component is exactly node_modules or dist; src/main.py and tests/test_main.py remain. That avoids a report dominated by generated bundles or installed dependencies.

The edge case is a legitimate source directory whose name merely contains the letters dist. A substring rule could discard it accidentally, while checking Path.parts does not. The assertion fixes the intended output and makes later additions to the ignored set a conscious policy change.

The list is not a universal definition of generated content. Python virtual environments, coverage output, and other package managers may need their own documented entries. Excluding a directory also means the scanner cannot make claims about files inside it; record that scope rather than interpreting an absent finding as inspection.

Complete example

from pathlib import Path

paths = [
    Path("src/main.py"),
    Path("node_modules/vendor.js"),
    Path("dist/bundle.js"),
    Path("tests/test_main.py"),
]
ignored = {"node_modules", "dist"}
kept = [str(path) for path in paths if not any(part in ignored for part in path.parts)]
assert kept == ["src/main.py", "tests/test_main.py"]
print("kept=2 ignored=2")

Expected stdout:

kept=2 ignored=2

Sources

- pathlib documentation

Prepared with AI assistance. The example uses synthetic data; its stated limits apply.

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