chore: add treefmt formatting (nix fmt + pre-commit + CI check)#4
Merged
Conversation
Wire treefmt via treefmt-nix: nixfmt, dhall format, purs-tidy (.tidyrc.json) and LuaFormatter for the FFI (.lua-format, kept over StyLua because it preserves the parentheses pslua's parser needs). `nix fmt` formats; the dev shell installs a content-based pre-commit hook and CI runs `nix fmt && git diff --exit-code` (content-based, since the in-place formatters bump mtime and would trip treefmt --fail-on-change). Lua lines budget 130 cols, matching the raised `luacheck --max-line-length`. The bulk of the diff is the first format pass.
There was a problem hiding this comment.
Pull request overview
Adds a repo-wide formatting workflow using treefmt-nix, exposing it via nix fmt, integrating it into CI as a formatting check, and documenting the developer-facing commands/config.
Changes:
- Introduce
treefmt-nixconfiguration (treefmt.nix) and formatter configs for PureScript (.tidyrc.json) and Lua FFI (.lua-format). - Wire
nix fmt/checks.formattinginto the flake and add a CI “Format check” step (nix fmt && git diff --exit-code). - Update docs and ignore rules to include the new formatter configuration files.
Reviewed changes
Copilot reviewed 7 out of 9 changed files in this pull request and generated 1 comment.
Show a summary per file
| File | Description |
|---|---|
| treefmt.nix | Adds treefmt-nix module config enabling nixfmt/dhall and custom formatters for purs-tidy + lua-format. |
| src/Effect/Exception.purs | Formatting-only change from purs-tidy. |
| flake.nix | Adds treefmt-nix input, exposes formatter + checks.formatting, and installs a pre-commit hook via shellHook. |
| flake.lock | Locks the new treefmt-nix flake input. |
| AGENTS.md | Documents nix fmt usage and updates luacheck max line length to 130. |
| .tidyrc.json | Adds purs-tidy configuration. |
| .lua-format | Adds LuaFormatter configuration for FFI sources. |
| .gitignore | Stops ignoring the new dotfile formatter configs so they are tracked. |
| .github/workflows/ci.yml | Adds format-check step and aligns luacheck max line length with docs. |
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Roll the ecosystem formatting setup (ADR 0007, piloted in purescript-lua/purescript-lua-effect#6) onto this fork.
Tooling. Copies
treefmt.nix/.tidyrc.json/.lua-formatand wires treefmt-nix into the flake:nix fmtformats,checks.formattingis exposed, the dev shell installs a content-based pre-commit hook, and CI gains a format-check step. The check is content-based (nix fmt && git diff --exit-code) rather thantreefmt --ci, since the in-place formatters bump mtime even when content is unchanged. LuaFormatter is kept over StyLua because it preserves the parentheses pslua's foreign-file parser requires;luacheck --max-line-lengthraised to 130 to match.Diff. The bulk is the first
nix fmtpass over*.pursand the*.luaFFI. Verified locally: build +luacheck --max-line-length 130green.