rust.yml

name: Rust

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

env:
  CARGO_TERM_COLOR: always

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

jobs:
  build:
    runs-on: ubuntu-latest
    timeout-minutes: 30

    defaults:
      run:
        shell: devenv shell bash -- -e {0}

    steps:
      - name: Checkout
        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3

      - name: Install Nix
        uses: cachix/install-nix-action@8aa03977d8d733052d78f4e008a241fd1dbf36b3 # v31.10.6

      - name: Set up devenv cache
        uses: cachix/cachix-action@3ba601ff5bbb07c7220846facfa2cd81eeee15a1 # v16
        with:
          name: devenv

      - name: Install devenv
        shell: bash
        run: nix profile add nixpkgs#devenv

      # The Rust toolchain comes from the Nix rust-overlay, so cargo/rustc are
      # only on PATH inside `devenv shell`. Expose their bin dir to subsequent
      # action steps so rust-cache can probe the toolchain for its cache key.
      - name: Expose Rust toolchain to GitHub PATH
        run: dirname "$(command -v cargo)" >> "$GITHUB_PATH"

      - name: Cache Rust build
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2.9.1
        with:
          workspaces: lambda
          cache-on-failure: true
          save-if: ${{ github.ref == 'refs/heads/main' }}

      - name: Build
        run: cd lambda && cargo lambda build --arm64

      - name: Run tests
        run: cd lambda && cargo test