name: Sandbox - ephemeral runner + shared cache
on:
  push:
    branches: [ci/sandbox]
  workflow_dispatch:

jobs:
  cargo:
    runs-on: sandbox
    defaults:
      run:
        working-directory: sandbox
    steps:
      - uses: actions/checkout@v4

      - name: Where am I?
        run: |
          echo "runner : ${RUNNER_NAME}"
          echo "os     : $(grep PRETTY_NAME /etc/os-release | cut -d'"' -f2)"
          echo "uid    : $(id -u)  cgroup: $(head -c 40 /proc/self/cgroup)"
          command -v git >/dev/null && echo "git    : $(git --version)"

      - name: Toolchain
        run: |
          command -v cargo >/dev/null || { apt-get update -qq && apt-get install -y -qq --no-install-recommends rustc cargo >/dev/null; }
          cargo --version

      - name: Cache cargo deps and target
        uses: actions/cache@v4
        with:
          path: |
            ~/.cargo/registry
            ~/.cargo/git
            sandbox/target
          key: cargo-${{ hashFiles('sandbox/Cargo.lock') }}
          restore-keys: cargo-

      - name: Test
        run: cargo test 2>&1 | tail -6