distributed 4.0.1

# Reusable Rust quality gate for Distributed libraries and domain crates.
#
# Callers (this repo or any consumer):
#   jobs:
#     quality:
#       permissions:
#         contents: read
#         pull-requests: write   # required for coverage PR comments
#       uses: hops-ops/distributed/.github/workflows/quality.yaml@main
#       with:
#         cargo_test_args: "--verbose --locked"
#
# Pipeline: rustfmt → clippy (-D warnings) → build → test (+ coverage)
# When cargo_coverage is true (default), tests run under cargo-llvm-cov; on
# pull_request a sticky comment shows TOTAL coverage % (not the compile log).
#
# Does not run broker/DB integrations or --all-features (see sibling workflows).

name: Distributed Rust Quality

on:
  workflow_call:
    inputs:
      runs_on:
        description: GitHub-hosted runner label
        type: string
        required: false
        default: ubuntu-latest

      toolchain:
        description: Rust toolchain channel or version
        type: string
        required: false
        default: stable

      cargo_fmt:
        description: Run cargo fmt --check
        type: boolean
        required: false
        default: true

      cargo_clippy:
        description: Run cargo clippy with -D warnings
        type: boolean
        required: false
        default: true

      cargo_build:
        description: Run cargo build before tests
        type: boolean
        required: false
        default: true

      cargo_test:
        description: Run cargo test (or llvm-cov when cargo_coverage is true)
        type: boolean
        required: false
        default: true

      cargo_coverage:
        description: Collect coverage with cargo-llvm-cov and comment on PRs
        type: boolean
        required: false
        default: true

      cargo_build_args:
        description: Extra args for cargo build
        type: string
        required: false
        default: "--verbose"

      cargo_test_args:
        description: Extra args for cargo test / cargo llvm-cov
        type: string
        required: false
        default: "--verbose"

      cargo_clippy_args:
        description: Args after `cargo clippy` (include `--` flags for rustc/clippy)
        type: string
        required: false
        default: "--all-targets -- -D warnings"

      cargo_llvm_cov_args:
        description: Extra args for cargo llvm-cov (e.g. --workspace)
        type: string
        required: false
        default: ""

      rust_cache:
        description: Enable Swatinem/rust-cache
        type: boolean
        required: false
        default: true

jobs:
  quality:
    name: fmt · clippy · build · test · coverage
    runs-on: ${{ inputs.runs_on }}
    permissions:
      contents: read
      pull-requests: write
    env:
      CARGO_TERM_COLOR: always
      RUST_BACKTRACE: "1"

    steps:
      - name: Checkout
        uses: actions/checkout@v7
        with:
          persist-credentials: false

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@stable
        with:
          toolchain: ${{ inputs.toolchain }}
          # trybuild snapshots include const-eval call sites from the standard
          # library. Installing rust-src keeps those diagnostics portable
          # between local development and Linux CI.
          components: rustfmt, clippy, llvm-tools-preview, rust-src

      - name: Rust cache
        if: inputs.rust_cache
        uses: Swatinem/rust-cache@v2

      - name: Install cargo-llvm-cov
        if: inputs.cargo_test && inputs.cargo_coverage
        uses: taiki-e/install-action@cargo-llvm-cov

      - name: cargo fmt --check
        if: inputs.cargo_fmt
        run: cargo fmt --check

      - name: cargo clippy
        if: inputs.cargo_clippy
        run: cargo clippy ${{ inputs.cargo_clippy_args }}

      - name: cargo build
        if: inputs.cargo_build
        run: cargo build ${{ inputs.cargo_build_args }}

      # Run tests under llvm-cov and write lcov. Logs stay in the job log only —
      # they must not be tee'd into the PR comment body.
      - name: cargo llvm-cov (test + lcov)
        if: inputs.cargo_test && inputs.cargo_coverage
        shell: bash
        run: |
          set -euo pipefail
          cargo llvm-cov clean --workspace
          cargo llvm-cov \
            ${{ inputs.cargo_llvm_cov_args }} \
            ${{ inputs.cargo_test_args }} \
            --lcov \
            --output-path lcov.info

      # Quiet report only (no recompile / no test re-run noise in the file we post).
      - name: Coverage summary for PR and job summary
        if: inputs.cargo_test && inputs.cargo_coverage
        id: coverage
        shell: bash
        env:
          # Force plain text for the report file / PR comment
          CARGO_TERM_COLOR: never
          TERM: dumb
        run: |
          set -euo pipefail

          cargo llvm-cov report \
            ${{ inputs.cargo_llvm_cov_args }} \
            --summary-only \
            --color never \
            | tee coverage-summary.txt

          # llvm-cov TOTAL line usually ends with a percentage field, e.g.:
          # TOTAL   1234   56   95.46%   ...
          TOTAL_LINE="$(grep -E '^TOTAL' coverage-summary.txt | tail -n1 || true)"
          PCT="$(echo "$TOTAL_LINE" | grep -oE '[0-9]+([.][0-9]+)?%' | tail -n1 || true)"
          if [ -z "${PCT}" ]; then
            PCT="n/a"
          fi
          echo "total_pct=${PCT}" >> "$GITHUB_OUTPUT"
          echo "Coverage TOTAL: ${PCT}"

          RUN_URL="${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"

          {
            echo "## Code coverage"
            echo ""
            echo "**TOTAL: \`${PCT}\`**"
            echo ""
            echo "<details>"
            echo "<summary>Full summary table</summary>"
            echo ""
            echo '```'
            cat coverage-summary.txt
            echo '```'
            echo ""
            echo "</details>"
            echo ""
            echo "- LCOV artifact: download **\`lcov\`** from this workflow run"
            echo "- [Open workflow run](${RUN_URL})"
            echo ""
            echo "_Generated by \`hops-ops/distributed\` quality workflow (cargo-llvm-cov)._"
          } > coverage-comment.md

          cat coverage-comment.md >> "$GITHUB_STEP_SUMMARY"

      - name: Upload lcov artifact
        if: inputs.cargo_test && inputs.cargo_coverage
        uses: actions/upload-artifact@v7
        with:
          name: lcov
          path: lcov.info
          if-no-files-found: warn

      - name: cargo test
        if: inputs.cargo_test && !inputs.cargo_coverage
        run: cargo test ${{ inputs.cargo_test_args }}

      - name: Comment coverage on PR
        if: >
          inputs.cargo_test &&
          inputs.cargo_coverage &&
          github.event_name == 'pull_request'
        uses: marocchino/sticky-pull-request-comment@v3.0.5
        with:
          header: distributed-rust-coverage
          path: coverage-comment.md
          recreate: true