ci-generate.yaml

name: CI

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

jobs:
  drift-check:
    runs-on: ubuntu-latest
    env:
      REPO: ${{ github.event.repository.name }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@stable

      - name: Cache
        uses: Leafwing-Studios/cargo-cache@v2
        with:
          sweep-cache: true

      - name: Install cargo-generate
        run: |
          cargo install cargo-generate

      - name: Retain a copy of every generated file
        run: |
          for template_file in $(find . -type f -name "*.template"); do
            generated_file="${template_file%.template}"
            if [ -f "$generated_file" ]; then
              # Keep a copy to diff with the output of the next step
              cp "$generated_file" "${generated_file}.check"
            fi
          done

      - name: Generate from templates
        run: |
          # Note: we use cargo-generate itself here as our wrapping of the cargo-generate library
          # does not allow us to do useful things like --allow-commands and use local templates.
          cargo generate --path . --name "$REPO" --allow-commands

      - name: Check for drift between templates and generated files
        run: |
          for check_file in $(find "$REPO" -type f -name "*.check"); do
            generated_file="${check_file%.check}"
            if ! diff "$check_file" "$generated_file" > /dev/null; then
              echo "File $generated_file has drift from $generated_file.template:"
              diff "$check_file" "$generated_file"
              echo "::error file=$generated_file::Template drift detected."
            fi
          done

      - name: Remove check files
        run: |
          find . -type f -name "*.check" -delete
          rm -rf "$REPO"