fix-ruff-violations

name	fix-ruff-violations
description	Use when expanding Ruff lint enforcement in CI or fixing batches of existing Ruff violations in src/wrinklefe. Triggers on requests like "fix ruff", "clean up lint", "expand lint scope", "address issue

Fixing Ruff violations in wrinkleFE

Current state

• Full Ruff config lives in pyproject.toml under [tool.ruff.lint]: select = ["E", "F", "W", "I", "N", "UP"], line-length 100, target py310.
• CI does NOT enforce that full set yet. .github/workflows/lint.yml runs only the starter scope: ruff check --select E9,F63,F7,F82 .
• ~840 violations across the repo are deferred. Tracked in issue #87.
• The goal is to incrementally widen CI's --select list until it matches pyproject.toml.

Workflow

1. Pick ONE rule family to expand next (e.g. I imports, UP pyupgrade, W whitespace). Smaller families first reduces blast radius per PR.
2. Scope the work:

   ruff check --select <FAMILY> src/wrinklefe tests app.py streamlit_viz.py
   

3. Apply autofixes where safe:

   ruff check --select <FAMILY> --fix src/wrinklefe tests app.py streamlit_viz.py
   

4. Hand-fix anything left. Do NOT silence with blanket # noqa — use per-line # noqa: <CODE> only when the rule is genuinely wrong for that line.
5. Run the full test suite (pytest) — autofixes occasionally break semantics (e.g. UP rewrites can shift behavior on edge cases).
6. Once the family is clean, add it to lint.yml's --select list so CI starts enforcing it. Update the comment on lines 30-32 of lint.yml to reflect the new scope.

Gotchas

• N (naming) hits scientific math hard. Identifiers like E, K, sigma_x, D_matrix, single-letter Voigt indices match real domain conventions. Prefer per-file # noqa: N806 (or N803 for arg names) over renaming domain terms. Discuss before renaming anything that appears in core/transforms.py, elements/, or failure/.
• I (isort) can reorder past # type: ignore comments — verify mypy still passes after autofix.
• Keep diffs minimal: don't reformat unrelated lines just because Ruff also flagged them in passing.
• app.py and streamlit_viz.py live at the repo root, not under src/. Make sure your scope includes them.

Done check

• ruff check --select <FAMILY> . exits clean.
• pytest passes.
• .github/workflows/lint.yml --select list updated.
• PR references issue #87.