name: Benchmark

on: [pull_request]
jobs:
  bench:
    runs-on: ${{ matrix.os }}

    strategy:
      fail-fast: false
      matrix:
        ghc: ['8.10.2', '8.8.4', '8.6.5']
        os: [ubuntu-latest, macOS-latest]

    steps:
    - uses: actions/checkout@v2
    - run: git fetch origin master # check the master branch for benchmarking
    - uses: actions/setup-haskell@v1
      with:
        ghc-version: ${{ matrix.ghc }}
        cabal-version: '3.2'
        enable-stack: false

    - name: Cache Cabal
      uses: actions/cache@v2
      with:
        path: |
          ~/.cabal/packages
          ~/.cabal/store
        key: ${{ runner.os }}-${{ matrix.ghc }}-cabal-bench

    - run: cabal update

    - run: cabal configure --enable-benchmarks

    - name: Build
      shell: bash
      # Retry it three times to workaround compiler segfaults in windows
      run: cabal build || cabal build || cabal build

    - name: Bench
      shell: bash
      # run the tests without parallelism, otherwise tasty will attempt to run
      # all test cases simultaneously which causes way too many hls
      # instances to be spun up for the poor github actions runner to handle
      run: cabal bench

    - name: Display results
      shell: bash
      run: |
        column -s, -t < bench-results/results.csv | tee bench-results/results.txt

    - name: Archive benchmarking artifacts
      uses: actions/upload-artifact@v2
      with:
        name: bench-results-${{ runner.os }}-${{ matrix.ghc }}
        path: |
           bench-results/results.*
           bench-results/**/*.svg