name: CI

on:
  push:
    branches: [main]
  pull_request:

env:
  CARGO_TERM_COLOR: always
  RUSTFLAGS: -D warnings

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        include:
          # The build most consumers get.
          - name: default
            features: ""
            profile: ""
          # Most numerical goldens need `approx` for assert_ulps_eq.
          - name: approx
            features: "--features approx"
            profile: ""
          # The parallel path, including tests/determinism.rs.
          - name: rayon
            features: "--features approx,rayon"
            profile: ""
          # Critical: debug_assert! is compiled out here, which is where the
          # tie/p_draw and score_sigma validation actually has to hold.
          - name: release
            features: "--features approx"
            profile: "--release"
    name: test (${{ matrix.name }})
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      - run: cargo test ${{ matrix.profile }} ${{ matrix.features }}
      - run: cargo test ${{ matrix.profile }} ${{ matrix.features }} --doc

  determinism:
    name: determinism across thread counts
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
      - uses: Swatinem/rust-cache@v2
      # Posteriors must be bit-identical regardless of how many rayon workers
      # run the color-group sweep.
      - run: |
          for threads in 1 2 4 8; do
            echo "== RAYON_NUM_THREADS=$threads =="
            RAYON_NUM_THREADS=$threads cargo test --release \
              --features approx,rayon --test determinism
          done

  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
        with:
          components: clippy
      - uses: Swatinem/rust-cache@v2
      - run: cargo clippy --all-targets --all-features -- -D warnings

  format:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      # rustfmt.toml uses nightly-only options (imports_granularity).
      - uses: dtolnay/rust-toolchain@nightly
        with:
          components: rustfmt
      - run: cargo +nightly fmt --check

  msrv:
    name: minimum supported Rust version
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@1.85.0
      - uses: Swatinem/rust-cache@v2
      - run: cargo check --all-targets --features approx,rayon