---
name: check
description: Format, lint, test, and build. Use before every commit.
---

# Check

Run every command in the Nix development shell. Use
`nix develop -c COMMAND` when direnv does not load the shell.

## Procedure

1. Format all files with `bin/format`.
2. Run the checks with `bin/check`. Its golangci-lint config keeps the
   standard linters and adds `errorlint`, `gocritic`, `testifylint`,
   `revive`, `wrapcheck`, `nlreturn`, and `wsl_v5`. These checks cover
   only part of the Go rules. A pass is not proof of compliance.
3. Run `git add` on new files, then run `nix build` and
   `nix flake check`.
4. Fix every failure and run the steps again. Do not disable a linter or
   add a `nolint` directive to get a pass. An intentional error discard
   needs the user's approval, an explicit directive, and a comment that
   gives the reason, as the `go-code` skill requires. Never replace a
   checked error with a blank assignment to get a pass.
5. Review the final diff against the rules. Passing tools do not replace
   this review.
   - Read `AGENTS.md` and the `SKILL.md` of each skill of the task again
     from disk now. Do not work from memory of an earlier read.
   - Go through the diff one rule at a time, and for each rule look at
     every changed line that it covers. For Go code, check each section
     of `go-code`, also for the tests. Check declaration order, owning
     test filenames, separators after multiline constructs, and errors
     assigned to `_`. Inspect blank-assigned errors even when `errcheck`
     reports none: `.golangci.yml` does not enable its `check-blank`
     setting. Check whole comment paragraphs against the `docs` skill,
     not only their line width.
   - Fix each finding, then run steps 1 to 4 again.

Tell the user about each check that cannot run and each failure that
stays.