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# Cancel superseded runs on the same ref (e.g. rapid pushes to a PR).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 ilp-highs -- -D warnings

  # 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: "ilp-highs 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"

      # The subprocess example tests (tests/suites/examples.rs) shell out to
      # `cargo run --example … --features ilp-highs`. Pre-build those example
      # binaries with that exact feature set so the subprocess reuses artifacts
      # instead of recompiling the whole crate mid-test (which otherwise adds
      # 60s+ to a single test's wall-clock and would trip the nextest timeout).
      - name: Build examples (for subprocess tests)
        run: cargo build --examples --features ilp-highs

      - 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. Feature set intentionally matches the historical coverage gate
  # (ilp-highs only) to keep the 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 --features ilp-highs --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 }}