ci.yml

name: CI

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

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

jobs:
  # TODO: We might want to later fix the version of clang-format so that future checks
  # don't mysteriously fail when a new version is released.
  style-check:
    name: Style check (clang-format)
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Install clang-format
        run: |
          sudo apt-get update
          sudo apt-get install -y clang-format
          echo "CLANG_FORMAT=clang-format" >> $GITHUB_ENV

      - name: Check formatting
        run: |
          mapfile -t FILES < <(git ls-files '*.[ch]pp' '*.c' '*.h')
          if [ ${#FILES[@]} -eq 0 ]; then
            echo "No source files to check"; exit 0
          fi
          echo "clang-format version: $($CLANG_FORMAT --version)"
          echo "Running clang-format diff..."
          bad_files=()

          for f in "${FILES[@]}"; do
            CF_CMD="$CLANG_FORMAT -style=file $f"

            if ! diff -u "$f" <($CF_CMD); then
              echo "::group::❌ $f"
              echo "Command: $CF_CMD"
              diff -u "$f" <($CF_CMD) || true
              echo "::endgroup::"
              bad_files+=("$f")
            fi
          done

          if [ ${#bad_files[@]} -ne 0 ]; then
            file_list=$(printf '%s\n' "${bad_files[@]}")
            file_list_escaped=${file_list//$'\n'/%0A}
            echo "::error::clang-format issues detected in the following files:%0A${file_list_escaped}%0ARun 'clang-format -i' to fix."
            exit 1
          fi

  docs-check:
    name: Docs check
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4

      - name: Install tools
        run: |
          sudo apt-get update -y
          sudo npm install -g markdown-link-check@^3 markdownlint-cli2@^0 cspell@^8

      - name: Check broken links
        run: |
          markdown-link-check -q -c .markdown-link-check.json README.md

      - name: Check typos
        run: |
          if ! npx cspell "README.md" --no-progress --no-summary; then
                echo "::error::cspell found unknown words. \
          If a word is correct, add it to .cspell.json under \"words\"."
                exit 1
              fi

      - name: Check formatting
        run: |
          markdownlint-cli2 README.md

  build:
    name: "Build (${{ matrix.name }})"
    runs-on: ${{ matrix.os }}
    needs: [style-check, docs-check]
    strategy:
      fail-fast: false # Make sure if one build fails, others can still run
      matrix:
        include:
          # Linux
          - os: ubuntu-latest
            compiler: gcc
            version: 13
            build_type: Release
            name: ubuntu-release-gcc
          - os: ubuntu-latest
            compiler: clang
            version: 16
            build_type: Release
            name: ubuntu-release-clang
          - os: ubuntu-latest
            compiler: gcc
            version: 13
            build_type: Debug
            name: ubuntu-debug-gcc
          - os: ubuntu-latest
            compiler: clang
            version: 16
            build_type: Debug
            name: ubuntu-debug-clang
          # Linux arm
          - os: ubuntu-24.04-arm
            compiler: clang
            version: 16
            build_type: Release
            name: ubuntu-arm64-release-clang
          - os: ubuntu-24.04-arm
            compiler: clang
            version: 16
            build_type: Debug
            name: ubuntu-arm64-debug-clang
          # macOS
          - os: macos-14
            compiler: apple-clang
            version: ""
            build_type: Release
            name: macos-release-appleclang
          - os: macos-14
            compiler: apple-clang
            version: ""
            build_type: Debug
            name: macos-debug-appleclang

    steps:
      - uses: actions/checkout@v4

      - name: Setup Python & Conan
        run: |
          python3 -m venv .venv
          source .venv/bin/activate
          pip install -U pip wheel conan==2.16.1 cmake==3.30.0
          conan remote update conancenter --url=https://center2.conan.io
          conan profile detect

      - name: Install compiler (Linux only)
        if: runner.os == 'Linux'
        run: |
          sudo apt-get update
          if [[ "${{ matrix.compiler }}" == "gcc" ]]; then
            sudo apt-get install -y gcc-${{ matrix.version }} g++-${{ matrix.version }}
            echo "CC=gcc-${{ matrix.version }}"  >> $GITHUB_ENV
            echo "CXX=g++-${{ matrix.version }}" >> $GITHUB_ENV
          else
            sudo apt-get install -y clang-${{ matrix.version }} lld
            echo "CC=clang-${{ matrix.version }}"   >> $GITHUB_ENV
            echo "CXX=clang++-${{ matrix.version }}" >> $GITHUB_ENV
          fi
      # We only perform static builds so the output can be exported as an artifact
      # for testing on a clean system without installing dependencies.
      - name: Download Dependencies
        run: |
          source .venv/bin/activate
          conan install . \
            --output-folder build \
            --build=missing \
            -s build_type=${{ matrix.build_type }} \
            -s compiler.cppstd=20 \
            -o "*:shared=False" \
            -o "*:fPIC=False"

      - name: Configure & build
        run: |
          source .venv/bin/activate

          if [[ "${{ runner.os }}" == "Linux" ]]; then
              FIND_SUFFIX='-DCMAKE_FIND_LIBRARY_SUFFIXES=.a'
              EXE_FLAGS='-static -static-libstdc++ -static-libgcc -pthread'
          else
              FIND_SUFFIX=''
              EXE_FLAGS=''
          fi

          cmake -S . -B build \
            -DCMAKE_TOOLCHAIN_FILE=build/build/${{ matrix.build_type }}/generators/conan_toolchain.cmake \
            -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} \
            -DBUILD_SHARED_LIBS=OFF \
            -DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
            ${FIND_SUFFIX} \
            -DCMAKE_EXE_LINKER_FLAGS="${EXE_FLAGS}"
          cmake --build build -j$(nproc || sysctl -n hw.ncpu)

      - name: Package build folder
        run: tar -czf build-${{ matrix.name }}.tar.gz build

      - name: Upload artefact
        uses: actions/upload-artifact@v4
        with:
          name: ${{ matrix.name }}
          path: build-${{ matrix.name }}.tar.gz

  build-sanitize:
    name: "Build (${{ matrix.san }})"
    runs-on: ubuntu-latest
    needs: [style-check, docs-check]

    strategy:
      fail-fast: false
      matrix:
        include:
          # ASan and UBSan can be used together, but TSan is incompatible with ASan.
          # But we keep ASan and UBSan builds separate separate because it isolates
          # memory- and UB-errors for clearer diagnostics.
          - san: asan # AddressSanitizer + LeakSanitizer (ASan + LSAn)
            flag: address,leak
          - san: ubsan # UndefinedBehaviorSanitizer
            flag: undefined
          - san: tsan # ThreadSanitizer
            flag: thread

    steps:
      - uses: actions/checkout@v4

      - name: Setup Python & Conan
        run: |
          python3 -m venv .venv
          source .venv/bin/activate
          pip install -U pip wheel conan==2.16.1 cmake==3.30.0
          conan remote update conancenter --url=https://center2.conan.io
          conan profile detect

      # We only run sanitizers on Linux with Clang, since GCC's support is less mature
      # and sanitizer support on macOS is incomplete.
      - name: Install clang-16
        run: |
          sudo apt-get update
          sudo apt-get install -y clang-16 lld-16
          echo "CC=clang-16"    >> $GITHUB_ENV
          echo "CXX=clang++-16" >> $GITHUB_ENV

      - name: Download dependencies
        run: |
          source .venv/bin/activate
          conan install . \
            --output-folder build \
            --build=missing \
            -s build_type=Debug \
            -s compiler.cppstd=20 \
            -o "*:shared=False"

      - name: Configure & build
        run: |
          source .venv/bin/activate
          cmake -S . -B build \
            -DCMAKE_TOOLCHAIN_FILE=build/build/Debug/generators/conan_toolchain.cmake \
            -DCMAKE_BUILD_TYPE=Debug \
            -DBUILD_SHARED_LIBS=OFF \
            -DCMAKE_EXPORT_COMPILE_COMMANDS=ON \
            -DCMAKE_CXX_FLAGS="-fsanitize=${{ matrix.flag }} -fno-omit-frame-pointer" \
            -DCMAKE_EXE_LINKER_FLAGS="-fsanitize=${{ matrix.flag }}"
          cmake --build build -j$(nproc)

      - name: Package build folder
        run: tar -czf build-${{ matrix.san }}.tar.gz build

      - name: Upload artefact
        uses: actions/upload-artifact@v4
        with:
          name: ${{ matrix.san }}
          path: build-${{ matrix.san }}.tar.gz

  # ─────────────────────────── Unit Tests ───────────────────────────
  unit-tests:
    name: "Unit tests (${{ matrix.target }})"
    needs: [build, build-sanitize]
    strategy:
      fail-fast: false
      matrix:
        include:
          - { target: ubuntu-release-gcc,         os: ubuntu-latest }
          - { target: ubuntu-release-clang,       os: ubuntu-latest }
          - { target: ubuntu-debug-gcc,           os: ubuntu-latest }
          - { target: ubuntu-debug-clang,         os: ubuntu-latest }
          - { target: ubuntu-arm64-release-clang, os: ubuntu-24.04-arm }
          - { target: ubuntu-arm64-debug-clang,   os: ubuntu-24.04-arm }
          - { target: macos-release-appleclang,   os: macos-14 }
          - { target: macos-debug-appleclang,     os: macos-14 }
          - { target: asan,                       os: ubuntu-latest }
          - { target: ubsan,                      os: ubuntu-latest }
          - { target: tsan,                       os: ubuntu-latest }
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/download-artifact@v4
        with:
          name: ${{ matrix.target }}

      - name: Unpack build folder
        run: tar -xzf build-${{ matrix.target }}.tar.gz

      - name: Unit tests
        run: |
          ctest --test-dir build -L unit --output-on-failure

  # ────────────────────────── Stress Tests ──────────────────────────
  stress-tests:
    name: "Stress tests (${{ matrix.target }})"
    needs: [build, build-sanitize]
    strategy:
      fail-fast: false
      matrix:
        include:
          - { target: ubuntu-release-gcc,         os: ubuntu-latest }
          - { target: ubuntu-release-clang,       os: ubuntu-latest }
          - { target: ubuntu-debug-gcc,           os: ubuntu-latest }
          - { target: ubuntu-debug-clang,         os: ubuntu-latest }
          - { target: ubuntu-arm64-release-clang, os: ubuntu-24.04-arm }
          - { target: ubuntu-arm64-debug-clang,   os: ubuntu-24.04-arm }
          - { target: macos-release-appleclang,   os: macos-14 }
          - { target: macos-debug-appleclang,     os: macos-14 }
          - { target: asan,                       os: ubuntu-latest }
          - { target: ubsan,                      os: ubuntu-latest }
          - { target: tsan,                       os: ubuntu-latest }
    runs-on: ${{ matrix.os }}

    steps:
      - uses: actions/checkout@v4

      - uses: actions/download-artifact@v4
        with:
          name: ${{ matrix.target }}

      - name: Unpack build folder
        run: tar -xzf build-${{ matrix.target }}.tar.gz

      - name: Stress tests
        run: |
          ctest --test-dir build -L stress --output-on-failure

  # ──────────────────── Performance comparison ────────────────────
  perf-tests:
    if: github.event_name == 'pull_request'
    name: Performance comparison (main, ${{ matrix.name }})
    needs: build
    runs-on: ${{ matrix.os }}
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-latest
            compiler: clang
            version: 16
            build_type: Release
            name: ubuntu-release-clang

    permissions:
      contents: read

    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 1

      # PR artefact from the build job
      - uses: actions/download-artifact@v4
        with:
          name: ${{ matrix.name }}

      - name: Unpack PR artefact
        run: |
          mkdir -p build-pr
          tar -xzf build-${{ matrix.name }}.tar.gz -C build-pr
          chmod +x build-pr/build/cartogram

      # Only designed to work on Linux
      - name: Setup Python & Conan
        run: |
          sudo apt-get update
          sudo apt-get install -y \
            ${{ matrix.compiler }}-${{ matrix.version }} \
            lld hyperfine python3-venv
          echo "CC=${{ matrix.compiler }}-${{ matrix.version }}"   >> $GITHUB_ENV
          echo "CXX=${{ matrix.compiler }}++-${{ matrix.version }}" >> $GITHUB_ENV

      - name: Build baseline (origin/main)
        run: |
          git fetch --depth 1 --no-tags origin main
          git worktree add ../baseline origin/main
          pushd ../baseline
          python3 -m venv .venv
          source .venv/bin/activate
          pip install --upgrade pip wheel conan==2.16.1 cmake==3.30.0
          conan remote update conancenter --url=https://center2.conan.io
          conan profile detect
          conan install . --output-folder build \
                          --build missing \
                          -s build_type=${{ matrix.build_type }} \
                          -s compiler.cppstd=20 \
                          -o "*:shared=False"
          cmake -S . -B build \
                -DCMAKE_TOOLCHAIN_FILE=build/build/${{ matrix.build_type }}/generators/conan_toolchain.cmake \
                -DCMAKE_BUILD_TYPE=${{ matrix.build_type }} \
                -DBUILD_SHARED_LIBS=OFF
          cmake --build build -j"$(nproc)"
          popd

      # Benchmarks
      - name: Benchmark sample_data maps
        run: |
          python3 -m venv .venv
          source .venv/bin/activate
          bash .github/scripts/benchmark_maps.sh \
            build-pr/build/cartogram \
            ../baseline/build/cartogram \
            results.json

      # Generate performance report
      - name: Create performance report
        run: |
          source .venv/bin/activate
          pip install --upgrade scipy
          python .github/scripts/gen_perf_comment.py results.json comment.md

      # When PR is made from fork, the pull_request will be empty during workflow_run in
      # pr-comment.yml. So, we also pass the PR number as artifact
      - name: Save PR number
        run: echo "${{ github.event.number }}" > pr_number.txt

      # Upload report for the pr-comment.yml workflow
      - name: Upload performance report & PR number
        uses: actions/upload-artifact@v4
        with:
          name: perf-comment # If this name changes, update the pr-comment.yml workflow too
          path: |
            comment.md
            pr_number.txt

  # ─────────────────────────── Fuzzer Tests ─────────────────────────
  # fuzzer-tests:
  #   needs: [build]
  #   strategy:
  #     fail-fast: false
  #     matrix:
  #       target:
  #         - ubuntu-release-gcc
  #         - ubuntu-release-clang
  #         - macos-release-appleclang
  #   runs-on: "${{ contains(matrix.target, 'mac') && 'macos-14' || 'ubuntu-latest' }}"

  #   steps:
  #     - uses: actions/checkout@v4

  #     - uses: actions/download-artifact@v4
  #       with:
  #         name: ${{ matrix.target }}

  #     - name: Install Python in venv
  #       run: |
  #         python3 -m venv .venv
  #         source .venv/bin/activate
  #         pip install -U pip

  #     - name: Unpack build folder
  #       run: tar -xzf build-${{ matrix.target }}.tar.gz

  #     - name: Fuzzer tests
  #       run: |
  #         ctest --test-dir build -L fuzzer --verbose