build-without-lockfile.yml

name: Build without committed Cargo.lock

on:
  push:
    branches:
      - main
      - release-*
    tags:
      # YYYYMMDD
      - "20[0-9][0-9][0-1][0-9][0-3][0-9]*"
  schedule:
    - cron: "0 0 * * 1"
  pull_request:
    # Only run on PRs if dependencies were modified.
    paths:
      - "**/Cargo.toml"
      - "**/Cargo.lock"
  workflow_dispatch:

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

jobs:
  build-ignore-lockfile:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4

      - name: Enable Rust Caching
        uses: Swatinem/rust-cache@v2
        with:
          prefix-key: v1-rust

      - name: Build without committed Cargo.lock
        run: |
          cargo generate-lockfile
          cargo check --all-targets

      - name: Comment on PR
        uses: actions/github-script@v7
        if: failure() && github.event_name == 'pull_request'
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const issue_number = context.issue.number;
            const owner = context.repo.owner;
            const repo = context.repo.repo;
            const runUrl = `https://github.com/${process.env.GITHUB_REPOSITORY}/actions/runs/${process.env.GITHUB_RUN_ID}`;

            const commentTitle = "Unable to build without Cargo.lock file"
            const commentBody = `${commentTitle}.

            This means that after this change 3rd party projects may have
            difficulties using crates in this repo as a dependency. If this
            isn't easy to fix please open an issue so we can fix it later.

            For the first failing build see: ${runUrl}

            To reproduce locally run

            \`\`\`
            cargo generate-lockfile
            cargo check --all-targets
            \`\`\`

            This PR can still be merged.`;

            // Fetch existing comments
            const { data: comments } = await github.rest.issues.listComments({
              owner,
              repo,
              issue_number,
            });

            // Find existing comment
            const existingComment = comments.find(c => c.body.startsWith(commentTitle));
            if (!existingComment) {
              await github.rest.issues.createComment({
                owner,
                repo,
                issue_number,
                body: commentBody
              });
            } else {
              console.log("Already commented.")
            }