RustCrypto-signatures/.github/workflows/mutation-testing.yml

name: Mutation Testing

# Minimal permissions for security
permissions:
  contents: read

on:
  # Run weekly on Sundays at 3 AM UTC (offset from KEMs to avoid resource contention)
  schedule:
    - cron: "0 3 * * 0"
  # Allow manual triggering
  workflow_dispatch:
    inputs:
      package:
        description: "Package to test (select 'all' for all packages)"
        required: false
        default: "all"
        type: choice
        options:
          - all
          - ml-dsa
          - slh-dsa
          - ecdsa
          - dsa

env:
  CARGO_INCREMENTAL: 0
  CARGO_TERM_COLOR: always
  RUST_MIN_STACK: 6291456

# Only run one mutation test at a time
concurrency:
  group: mutation-testing
  cancel-in-progress: false

jobs:
  mutants:
    name: ${{ matrix.package }}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        package:
          - ml-dsa
          - slh-dsa
        # Only filter if a specific package was requested via workflow_dispatch
        exclude:
          - package: ${{ github.event.inputs.package != 'all' && github.event.inputs.package != 'ml-dsa' && 'ml-dsa' || 'NONE' }}
          - package: ${{ github.event.inputs.package != 'all' && github.event.inputs.package != 'slh-dsa' && 'slh-dsa' || 'NONE' }}
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v4.2.2
        with:
          persist-credentials: false
          submodules: recursive

      - uses: dtolnay/rust-toolchain@stable
        with:
          toolchain: stable

      - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4  # v2.9.1
        with:
          prefix-key: mutants-${{ matrix.package }}

      - name: Install cargo-mutants
        run: cargo install cargo-mutants@26.1.2 --locked

      - name: Run mutation testing
        run: |
          cargo mutants --package "${{ matrix.package }}" --all-features -j 2 --timeout 300 2>&1 | tee mutants-output.txt
          # Extract summary for job summary
          {
            echo "## Mutation Testing Results: ${{ matrix.package }}"
            echo ""
            echo '```'
            tail -20 mutants-output.txt
            echo '```'
          } >> "$GITHUB_STEP_SUMMARY"

      - name: Upload mutation results
        uses: actions/upload-artifact@v7
        if: always()
        with:
          name: mutants-${{ matrix.package }}
          path: |
            mutants.out/
            mutants-output.txt
          retention-days: 30

      - name: Check for missed mutants
        if: always()
        run: |
          if [ -f mutants.out/missed.txt ] && [ -s mutants.out/missed.txt ]; then
            echo "::warning::Some mutations were not caught by tests"
            {
              echo "### Missed Mutations"
              echo '```'
              cat mutants.out/missed.txt
              echo '```'
            } >> "$GITHUB_STEP_SUMMARY"
          fi