rustbench.yml

on:
  pull_request:
    paths:
    - '**.rs'
    - '**/Cargo.toml'
  workflow_dispatch:

name: Benchmark

permissions:
  pull-requests: write

jobs:
  benchmark:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v4

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

    - name: Cache dependencies
      uses: Swatinem/rust-cache@v2

    - name: Install Critcmp
      uses: baptiste0928/cargo-install@v3
      with:
        crate: critcmp
        version: latest

    - name: Run Benchmarks on changes
      run: |
        cargo bench --workspace --bench bench -- --save-baseline default_changes
        cargo bench --workspace --bench bench --features forbid_unsafe  -- --save-baseline forbid_unsafe_changes

    - uses: actions/checkout@v4
      with:
        ref: ${{ github.event.pull_request.base.sha }}
        clean: false

    - name: Run Benchmarks before changes
      run: |
        cargo bench --workspace --bench bench -- --save-baseline default_before

        # Skip benchmarking for forbid_unsafe feature if the PR base commit doesn't have the feature
        if [[ "$(grep forbid_unsafe Cargo.toml)" ]]; then
          cargo bench --workspace --bench bench --features forbid_unsafe -- --save-baseline forbid_unsafe_before
        fi

    - name: Compare benchmarks
      run: |
        echo 'results<<EOF' >> $GITHUB_OUTPUT
        critcmp default_before default_changes >> $GITHUB_OUTPUT
        echo 'EOF' >> $GITHUB_OUTPUT
      id: compare

    - name: Compare benchmarks for forbid-unsafe
      run: |
        echo 'results<<EOF' >> $GITHUB_OUTPUT
        if [[ "$(grep forbid_unsafe Cargo.toml)" ]]; then
          critcmp forbid_unsafe_before forbid_unsafe_changes >> $GITHUB_OUTPUT
        else 
          echo 'NOTE: PR base commit does not support the "forbid_unsafe" feature;' >> $GITHUB_OUTPUT
          echo 'comparing forbid_unsafe against the default features on base instead.' >> $GITHUB_OUTPUT
          critcmp default_before forbid_unsafe_changes >> $GITHUB_OUTPUT
        fi
        echo 'EOF' >> $GITHUB_OUTPUT
      id: compare-forbid-unsafe

    - name: Comment PR with benchmarks
      uses: thollander/actions-comment-pull-request@v2
      continue-on-error: true
      with:
        message: |
          Benchmark results with default features:
          ```
          ${{ steps.compare.outputs.results }}
          ```

          Benchmark results with feature "forbid_unsafe":
          ```
          ${{ steps.compare-forbid-unsafe.outputs.results }}
          ```

        comment_tag: benchmarks

      id: comment

    - name: If PR comment failed, write to PR summary
      if: steps.comment.outcome != 'success'
      run: |
        echo '### Benchmark results' >> $GITHUB_STEP_SUMMARY
        echo '```' >> $GITHUB_STEP_SUMMARY
        echo '${{ steps.compare.outputs.results }}' >> $GITHUB_STEP_SUMMARY
        echo '```' >> $GITHUB_STEP_SUMMARY

        echo '### Benchmark results with forbid-unsafe' >> $GITHUB_STEP_SUMMARY
        echo '```' >> $GITHUB_STEP_SUMMARY
        echo '${{ steps.compare-forbid-unsafe.outputs.results }}' >> $GITHUB_STEP_SUMMARY
        echo '```' >> $GITHUB_STEP_SUMMARY