name: CI
on: [push, pull_request]

jobs:
  # Here we're keeping on arbitrary LLVM version fixed and varying GCC.
  linux-gcc:
    strategy:
      fail-fast: false
      matrix:
        image:
          # List: https://github.com/conan-io/conan-docker-tools
          - gcc10
          - gcc9
          - gcc8
          - gcc7
          - gcc6

    runs-on: ubuntu-latest
    container:
      image: conanio/${{matrix.image}}
      options: --user root

    steps:
    - uses: actions/checkout@v2
    - name: Create Build Environment
      run: cmake -E make_directory build
    - name: Install libclang
      run: apt-get -qq update && apt-get install -y llvm clang libclang-dev
    - name: Install ninja
      run: type ninja || apt-get install -y ninja-build

    - name: Configure
      working-directory: build/
      run: cmake -GNinja $GITHUB_WORKSPACE
    - name: Build
      working-directory: build/
      run: cmake --build .
    - name: Test
      working-directory: build/
      run: ctest --output-on-failure

  # Here we're varying the LLVM version and using its clang for compiling as well.
  linux-clang:
    strategy:
      fail-fast: false
      matrix:
        version: [7, 8, 9, 10]

    runs-on: ubuntu-latest
    container:
      # Just one of the newer images.
      image: conanio/gcc10
      options: --user root

    steps:
    - uses: actions/checkout@v2
    - name: Create Build Environment
      run: cmake -E make_directory build
    - name: Install libclang
      run: apt-get -qq update && apt-get install -y llvm-${{matrix.version}} clang-${{matrix.version}} libclang-${{matrix.version}}-dev
    - name: Install ninja
      run: type ninja || apt-get install -y ninja-build

    - name: Configure
      working-directory: build/
      run: cmake -GNinja $GITHUB_WORKSPACE -DCMAKE_CXX_COMPILER=clang++-${{matrix.version}}
    - name: Build
      working-directory: build/
      run: cmake --build .
    - name: Test
      working-directory: build/
      run: ctest --output-on-failure