# Adapted from https://github.com/joshka/github-workflows/blob/main/.github/workflows/rust-check.yml
# Thanks to joshka for permission to use this template!
on:
  push:
    branches:
      - main
  pull_request:

name: Check

env:
  CARGO_TERM_COLOR: always

concurrency:
  group: ${{ github.workflow }}-${{ github.head_ref || github.run_id }}
  cancel-in-progress: true

jobs:
  fmt:
    name: stable / fmt
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v5

      - name: Install Rust stable
        uses: dtolnay/rust-toolchain@stable
        with:
          components: rustfmt

      - name: Run cargo fmt
        run: cargo fmt -- --check

      - name: Cache Cargo dependencies
        uses: Swatinem/rust-cache@v2

  clippy:
    name: ${{ matrix.toolchain }} / clippy
    runs-on: ubuntu-latest
    permissions:
      checks: write
    strategy:
      fail-fast: false
      matrix:
        # Get early warnings about new lints introduced in the beta channel
        toolchain: [stable, beta]
    steps:
      - name: Checkout
        uses: actions/checkout@v5

      - name: Install Rust stable
        uses: dtolnay/rust-toolchain@stable
        with:
          components: clippy

      - name: Run clippy action
        uses: clechasseur/rs-clippy-check@v5

      - name: Cache Cargo dependencies
        uses: Swatinem/rust-cache@v2
  doc:
    # run docs generation on nightly rather than stable. This enables features like
    # https://doc.rust-lang.org/beta/unstable-book/language-features/doc-cfg.html which allows an
    # API be documented as only available in some specific platforms.
    name: nightly / doc
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5

      - name: Install Rust nightly
        uses: dtolnay/rust-toolchain@nightly

      - name: Run cargo doc
        run: cargo doc --no-deps --all-features
        env:
          RUSTDOCFLAGS: --cfg docsrs
  msrv:
    # check that we can build using the minimal rust version that is specified by this crate
    name: 1.95.0 / check
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5

      - name: Install 1.95.0
        uses: dtolnay/rust-toolchain@master
        with:
          toolchain: 1.95.0

      - name: cargo +1.95.0 check
        run: cargo check

  dockerfile-msrv:
    # The Dockerfile's pinned Rust image is only built at release time, so a
    # rust-version bump that misses it fails silently until the next release.
    # Catch the drift on every push instead.
    name: dockerfile / msrv
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v5

      - name: Check Dockerfile Rust image against Cargo.toml rust-version
        run: |
          set -euo pipefail
          msrv=$(sed -nE 's/^rust-version = "([0-9.]+)"$/\1/p' Cargo.toml)
          image_tag=$(sed -nE 's/^FROM rust:([0-9.]+) AS builder$/\1/p' Dockerfile)
          : "${msrv:?failed to extract rust-version from Cargo.toml}"
          : "${image_tag:?failed to extract the rust image tag from the Dockerfile}"
          # The rust image tag pins major.minor, so compare on major.minor only
          msrv_mm=$(echo "$msrv" | cut -d. -f1,2)
          image_mm=$(echo "$image_tag" | cut -d. -f1,2)
          if [ "$(printf '%s\n' "$msrv_mm" "$image_mm" | sort -V | head -n1)" != "$msrv_mm" ]; then
            echo "Dockerfile builds with rust:$image_tag, but Cargo.toml declares rust-version = \"$msrv\"."
            echo "Cargo refuses to build under an older toolchain, so the release Docker publish step will fail."
            echo "Update the FROM rust:* line in the Dockerfile to at least $msrv_mm."
            exit 1
          fi
          echo "OK: Dockerfile rust:$image_tag satisfies rust-version $msrv"