Style gates (CI)¶

The cheapest-to-check rules of the UW3 Style Charter are machine-enforced on every pull request to development and main by .github/workflows/style-gates.yml. The job is fast (no PETSc build) and runs a single stdlib-only scanner: scripts/check_deprecated_patterns.py.

What the gate checks¶

Pattern id	Charter	Flags	Use instead
`access-context`	§7	`with mesh.access(...)` / `with swarm.access(...)`	the variable’s `.array` property directly
`mesh-data`	§7	`mesh.data` (coordinate read)	`mesh.X.coords`
`hedging-name`	§3	`def maybe_` / `def try_` / `def do_*` (and `_`-private forms)	a name stating what the function DOES
`except-pass`	§4	`except ...:` + bare `pass` with no comment nearby	a comment stating the sanctioned failure mode

Detection is line-based and deliberately simple; the exact heuristics (and the documented exclusions, e.g. commented-out lines and self.data inside Mesh methods) are in the scanner’s module docstring. A related regression net — tests/test_0641_wave_c_api_shims.py in the level_1 + tier_a CI gate — covers the deprecation warnings the shimmed APIs must keep emitting.

The allowlist only shrinks¶

scripts/deprecated_pattern_allowlist.txt records the legacy hits that existed when the gate was introduced (baseline: development @ 9f5ed9e9, 2026-07), one path:pattern-id per line. The gate fails on any hit not listed there.

Warning

The allowlist may only shrink. If your PR trips the gate, fix the code — do not add allowlist lines. Only a maintainer adds entries, and only for code that predates the gate. When you clean up a listed file, delete its entries; the scanner reminds you by reporting stale ones.

Running locally¶

pixi run -e amr-dev python scripts/check_deprecated_patterns.py                # the CI gate
pixi run -e amr-dev python scripts/check_deprecated_patterns.py --include-docs # + docs/ report
pixi run -e amr-dev python scripts/check_deprecated_patterns.py --no-allowlist # full legacy inventory

The scanner needs nothing beyond the Python standard library, so plain python scripts/check_deprecated_patterns.py works in any environment.

When your PR trips the gate¶

Read the flagged line(s) in the job log — each hit names its pattern id and the Charter rule it violates.
Fix the code (the table above gives the replacement for each pattern).
If you believe a hit is a false positive of the line-based heuristic, say so in the PR and ask a maintainer to rule — do not edit the allowlist yourself.

Formatting (not gated)¶

The tree is not currently black-clean (81 of 95 files at baseline), so there is no formatting gate — adding one would fail every PR that touches library code. Do not reformat files wholesale to “fix” this: bulk reformatting destroys git blame and turns reviewable diffs into unreviewable ones. If the maintainers later adopt a formatter, it will arrive as a single dedicated reformat commit plus a gate, not piecemeal.