ci.yml

name: ci

on:
  push:
    branches: [main]
  pull_request:

# One CI run per ref: cancel superseded runs on the same branch/PR.
concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

jobs:
  # ------------------------------------------------------------------
  # The suite that must stay green everywhere: pure Python + numpy, the
  # reference backends, the CLI, and the worked examples. No CUDA, no GPU.
  # ------------------------------------------------------------------
  cpu-tests:
    name: CPU tests (py${{ matrix.python }})
    runs-on: ubuntu-24.04
    strategy:
      fail-fast: false
      matrix:
        python: ["3.10", "3.11", "3.12"]
    steps:
      - uses: actions/checkout@v4

      - uses: actions/setup-python@v5
        with:
          python-version: ${{ matrix.python }}
          cache: pip

      # Installs the package the way a user does. The wheel is pure
      # Python (py3-none-any), so this is also the aarch64 story: no
      # compiler, no CUDA, no architecture-specific wheel needed.
      - name: Install
        run: |
          python -m pip install --upgrade pip
          python -m pip install -e ".[test]"

      - name: Import from outside the checkout
        working-directory: ${{ runner.temp }}
        run: |
          python -c "import coldcore; print('coldcore', coldcore.__version__)"
          coldcore --help
          python -m coldcore --help

      - name: Tests (CPU only)
        run: python -m pytest tests -v -k "not gpu"

      # CLI smoke on the reference backend: K_2(4,1) = 4, a 16-word space
      # that solves in well under a second.
      - name: CLI smoke
        working-directory: ${{ runner.temp }}
        run: |
          coldcore solve --backend ref -p q=2 -p n=4 -p R=1 \
              --floor 4 --notch-budget 5 --hours 0.02

  # ------------------------------------------------------------------
  # Lint. Deliberately permissive (see [tool.ruff] in pyproject.toml):
  # pyflakes + pycodestyle errors + obvious modernisations, no formatter,
  # no style bikeshedding. Pinned so a ruff release cannot turn main red.
  # ------------------------------------------------------------------
  lint:
    name: Lint (ruff)
    runs-on: ubuntu-24.04
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-python@v5
        with:
          python-version: "3.12"
      - run: python -m pip install ruff==0.16.4
      - run: ruff check --output-format=github .

  # ------------------------------------------------------------------
  # Compile-only CUDA build: proves the headers, the ABI and the plugin
  # sources still compile for sm_90. No device is present, so nothing is
  # executed.
  # ------------------------------------------------------------------
  cuda-build:
    name: CUDA compile-only (sm_90, no GPU)
    runs-on: ubuntu-24.04
    container: nvidia/cuda:12.4.1-devel-ubuntu22.04
    steps:
      - uses: actions/checkout@v4
      - run: apt-get update && apt-get install -y cmake git
      # the covering plugin kernels are in-tree (src/plugins/covering/), so
      # the full build compiles here; see VENDORED.md for upstream sync.
      - run: cmake -B build -DCMAKE_BUILD_TYPE=Release -DCOLDCORE_CUDA_ARCHS=90
      - run: cmake --build build -j 2
      - run: test -f build/lib/libcoldcore.so

  # ------------------------------------------------------------------
  # GPU parity tests. GitHub-hosted runners have no CUDA device, so this
  # job only makes sense on a self-hosted runner attached to the
  # maintainers' hardware (GH200). Until such a runner is registered the
  # GPU suite runs manually before release tags (see CONTRIBUTING.md).
  # To enable: register a runner with the labels below and uncomment.
  # ------------------------------------------------------------------
  # gpu-tests:
  #   name: GPU parity tests (self-hosted)
  #   runs-on: [self-hosted, linux, arm64, cuda]
  #   steps:
  #     - uses: actions/checkout@v4
  #     - run: python -m pip install -e ".[test]"
  #     - run: cmake -B build -DCMAKE_BUILD_TYPE=Release && cmake --build build -j
  #     - run: python -m pytest tests -v          # includes the gpu marker