pylance-check

name	pylance-check
description	Run pyright (Pylance engine) on Python files and fix every reported diagnostic. Use after any .py edit, before considering the task done. Enforced by AGENTS.md § Python (scrapers).

Pylance check

This repo enforces zero Pylance warnings on every .py file (see AGENTS.md § Python). The lint is reproducible via the open-source pyright engine wrapped by a durable script:

python _Helpers/scripts/fixes/lint_pylance.py <path>

• <path> = a single file, a folder, or omit it to lint the whole repo.
• Exit code 0 = clean, 1 = blocking diagnostics, 2 = tool error.
• --check makes it a dry-run (always exit 0).
• --strict makes warnings blocking too.

When to invoke

After any edit to a .py file, before considering the task done. Also useful as a sanity check before opening a PR / pushing to the public repo.

Typical workflow

# 1. Edit your .py file
# 2. Run the linter on the same file
python _Helpers/scripts/fixes/lint_pylance.py _Helpers/<your_script>.py

# 3. Fix every reported diagnostic, loop until clean.

# 4. (optional) Lint the whole repo as a smoke test
python _Helpers/scripts/fixes/lint_pylance.py

Common diagnostic patterns in this repo

Pattern	Root cause	Fix
"splitlines" is not a known attribute of "None"	__doc__: Optional[str] is None under python -OO	Use a module-level _DESCRIPTION constant, never __doc__.splitlines()
"existing" is possibly unbound	Variable assigned only inside a branch	Initialise before the branch: existing = ""
"append" is not a known attribute of "str"	tag.get("class") or [] keeps a str branch	Coerce: if isinstance(classes, str): classes = classes.split()
Cannot access attribute "startswith" for class "AttributeValueList"	BS4 Tag.attrs keys are over-typed in stubs	# type: ignore[attr-defined] or filter with isinstance
Argument of type "list[Any]" cannot be assigned to parameter "default"	BS4 Tag.get(key, default) rejects list as default	Drop the default and use get(key) or []

Installation

If pyright is missing:

pip install pyright

The script falls back to python -m pyright if the pyright binary is not on PATH.

Why this skill exists

Without it, AI agents (and humans) forget to lint after edits, and Pylance warnings pile up. The skill + the AGENTS.md rule together make the check automatic.