Checkmate - A flake checker (treefmt & nix-unit) for testing other flakes with zero dependencies.#

Checks include:

• treefmt - nixfmt, deadnix, mdformat, yamlfmt. See treefmt.nix.

• nix-unit - The flake being checked (ie, inputs.target) is expected to expose flakeModules.checkmate:

See import-tree or example

# Generate a new project including github CI action
nix flake new -t github:vic/checkmate

Running treefmt on your code#

# formatting your code
nix run github:vic/checkmate#treefmt -- $PWD

# see if code is formatted
nix run github:vic/checkmate#treefmt -- --ci $PWD

Running nix-unit tests locally#

# Since nix-unit runs on a sandbox the following will not work (probably a nix-unit issue?)
# nix run github:vic/checkmate#check-nix-unit --override-input target path:$PWD -L

# Instead you'll need to have to make a commit and run: (--refresh ensures you test the latest commit)
nix run github:vic/checkmate#check-nix-unit --override-input target git:$PWD -L --refresh

CI Usage#

On your github action:

on:
  pull_request:
  push:
    branches: [main]
jobs:
  flake-check:
    name: nix flake check
    runs-on: ubuntu-latest
    steps:
      - uses: cachix/install-nix-action@v30
      - run: nix flake check -L github:vic/checkmate --override-input target github:$GITHUB_REPOSITORY/
$GITHUB_SHA

As a fully working example, see:

https://github.com/vic/import-tree