ci.yml

name: CI

on:
  push:
    branches: [ main, develop ]
  pull_request:
    branches: [ main, develop ]

# Cancel superseded runs on the same ref (e.g. rapid pushes to a PR).
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

# Least privilege: jobs only read the repo; codecov auth is via token secret.
permissions:
  contents: read

env:
  CARGO_TERM_COLOR: always
  RUST_BACKTRACE: 1
  # Incremental compilation hurts cold CI builds and bloats the cache; disable it
  # (recommended by Swatinem/rust-cache).
  CARGO_INCREMENTAL: 0
  # Tolerate transient registry/network blips.
  CARGO_NET_RETRY: 10
  RUSTUP_MAX_RETRIES: 10

jobs:
  # Formatting — cheap, fails fast, no build/cache needed.
  fmt:
    name: Rustfmt
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: rustfmt
      - name: Check formatting
        run: cargo fmt --all --check

  # Lints.
  clippy:
    name: Clippy
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: clippy
      - uses: Swatinem/rust-cache@v2
      - name: Run clippy
        run: cargo clippy --all-targets --features example-db -- -D warnings

  # Build and exercise the HiGHS-backed CLI natively on Apple Silicon.
  macos-arm64:
    name: macOS ARM64 build & run
    runs-on: macos-15
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      - name: Verify ARM64 host
        run: "rustc -vV | grep 'host: aarch64-apple-darwin'"
      - name: Build workspace
        run: cargo build --workspace
      - name: Run CLI and ILP smoke test
        run: |
          target/debug/pred list | head -5
          target/debug/pred create MaximumIndependentSet --graph 0-1,1-2,2-3,3-4,4-0 -o mis.json
          target/debug/pred solve mis.json --solver ilp | tee solve.out
          grep -q '"kind": "ilp"' solve.out
          grep -q '"evaluation": "Max(2)"' solve.out

  # Build and exercise the HiGHS-backed CLI natively on 64-bit Windows.
  windows-x86_64:
    name: Windows x86_64 build & run
    runs-on: windows-2025
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      - name: Verify x86_64 host
        shell: pwsh
        run: |
          $hostInfo = rustc -vV | Out-String
          if ($hostInfo -notmatch 'host: x86_64-pc-windows-msvc') {
            throw "Unexpected Rust host:`n$hostInfo"
          }
      - name: Build workspace
        run: cargo build --workspace
      - name: Run CLI and ILP smoke test
        shell: pwsh
        run: |
          $pred = 'target/debug/pred.exe'
          & $pred list | Select-Object -First 5
          & $pred create MaximumIndependentSet --graph 0-1,1-2,2-3,3-4,4-0 -o mis.json
          & $pred solve mis.json --solver ilp | Tee-Object -FilePath solve.out
          $solveOutput = Get-Content solve.out -Raw
          if ($solveOutput -notmatch '"kind": "ilp"') {
            throw 'Expected the ILP solver to run'
          }
          if ($solveOutput -notmatch '"evaluation": "Max\(2\)"') {
            throw 'Expected the maximum independent set value to be 2'
          }

  # Cross-compile the full HiGHS-backed CLI to RISC-V Linux, then execute an
  # ILP solve under QEMU user-mode emulation (not just a link check).
  riscv:
    name: RISC-V build & run
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
        with:
          targets: riscv64gc-unknown-linux-gnu
      - uses: Swatinem/rust-cache@v2
      - name: Install RISC-V cross tools and QEMU
        run: |
          sudo apt-get update
          sudo apt-get install -y gcc-riscv64-linux-gnu g++-riscv64-linux-gnu binutils-riscv64-linux-gnu qemu-user
      - name: Build workspace for RISC-V
        env:
          CARGO_TARGET_RISCV64GC_UNKNOWN_LINUX_GNU_LINKER: riscv64-linux-gnu-gcc
          CC_riscv64gc_unknown_linux_gnu: riscv64-linux-gnu-gcc
          CXX_riscv64gc_unknown_linux_gnu: riscv64-linux-gnu-g++
        run: cargo build --workspace --target riscv64gc-unknown-linux-gnu
      - name: Verify RISC-V executable
        run: |
          riscv64-linux-gnu-readelf -h target/riscv64gc-unknown-linux-gnu/debug/pred \
            | grep 'Machine:.*RISC-V'
      - name: Run CLI smoke test under QEMU
        env:
          PRED: qemu-riscv64 -L /usr/riscv64-linux-gnu target/riscv64gc-unknown-linux-gnu/debug/pred
        run: |
          # Registry loads and the catalog renders on RISC-V.
          $PRED list | head -5
          # End-to-end reduction and HiGHS solve: MIS of a 5-cycle is 2.
          $PRED create MaximumIndependentSet --graph 0-1,1-2,2-3,3-4,4-0 -o mis.json
          $PRED solve mis.json --solver ilp | tee solve.out
          grep -q '"kind": "ilp"' solve.out
          grep -q '"evaluation": "Max(2)"' solve.out

  # Build, test (nextest), doc tests, and paper.
  test:
    name: Test
    runs-on: ubuntu-latest
    # Single feature set across compile + test + doctest so artifacts are reused
    # (no redundant full recompile between steps).
    env:
      FEATURES: "example-db"
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
      - uses: taiki-e/install-action@v2
        with:
          tool: nextest
      - uses: Swatinem/rust-cache@v2
      - name: Install typst
        uses: typst-community/setup-typst@v5

      - name: Compile tests
        run: cargo nextest run --no-run --workspace --features "$FEATURES"

      - name: Run tests
        run: cargo nextest run --workspace --features "$FEATURES"

      # nextest does not run doc tests; run them separately (reuses the build).
      - name: Run doc tests
        run: cargo test --doc --features "$FEATURES" --verbose

      - name: Build paper
        run: make paper

  # Coverage intentionally excludes the optional example database to keep the
  # historical codecov baseline stable.
  coverage:
    name: Code Coverage
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: llvm-tools-preview
      - uses: taiki-e/install-action@v2
        with:
          tool: cargo-llvm-cov,nextest
      - uses: Swatinem/rust-cache@v2
      - name: Generate coverage
        run: cargo llvm-cov nextest --workspace --lcov --output-path lcov.info
      - name: Upload to codecov.io
        uses: codecov/codecov-action@v5
        with:
          files: lcov.info
          fail_ci_if_error: false  # Don't fail CI if upload fails
          token: ${{ secrets.CODECOV_TOKEN }}