cabal-in-nix-shell.yml

name: Build & test in nix-shell

on:
  push:
  pull_request:

jobs:
  build_test:
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-22.04, ubuntu-20.04, macos-13, macos-14]
        ghc: [ghc865Binary, ghc884, ghc810]
        cc: [gcc8, gcc14, clang_12, clang_18]
    runs-on: ${{ matrix.os }}
    steps:
      - name: Checkout
        uses: actions/checkout@v3

      - name: Install Nix
        uses: cachix/install-nix-action@v25
        with:
          install_url: https://releases.nixos.org/nix/nix-2.20.5/install
          # NOTE: We avoid using arm64 builds of GHC (because they're mostly broken for early GHC versions) by specifying 'system = x86_64-darwin' for macOS runners
          extra_nix_config: |
            substituters = https://cache.nixos.org https://cache.iog.io
            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
            system-features = benchmark big-parallel kvm nixos-test
            ${{ startsWith(matrix.os, 'macos') && 'system = x86_64-darwin' || '' }}

      - name: Cache cabal files
        uses: actions/cache@v3
        with:
          path: |
            ~/.cabal/packages
            ~/.cabal/store
            dist-newstyle
          key: ${{ runner.os }}-${{ matrix.os }}-${{ hashFiles('**/*.cabal', '**/cabal.project', '**/cabal.project.freeze') }}--${{ matrix.ghc }}
          restore-keys: ${{ runner.os }}-${{ matrix.os }}-

      # Make nix-shell use specific Bash version.
      # Cf. https://nixos.org/manual/nix/stable/command-ref/nix-shell#environment-variables.
      - name: Set shell Bash
        run: echo "NIX_BUILD_SHELL=$(nix-build -A bash .github/workflows/bash.nix)/bin/bash" >> $GITHUB_ENV

      - name: Test nix-shell # test that the Nix shell actually works
        run: nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'echo $PATH; ls -l $(which ghc); ls -l $(which cabal); ghc --version; cabal --version; type cabal'

      - name: Export GHC version env var
        run: echo "GHC_VERSION=$(nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'ghc --numeric-version')" >> $GITHUB_ENV

      - name: Run 'cabal update'
        run: nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'cabal update'

      - name: Build library
        run: nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'cabal build lib:packman'

      - name: Build tests
        run: nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'cabal build --enable-tests'

        # NOTE: Ignores failures caused by https://github.com/jberthold/packman/issues/18.
        #       It's not very useful to have failing CI on the master branch, since it makes us miss newly introduced bugs. Therefore, we ignore this known error, while failing in case of other errors in the same test suite or failure of other test suites.
        #       The condition in human-readable terms is: (all_tests_succeeded || testmthread_logs_contain_issue18_error_string) && other_test_suites_did_not_fail
        #         The condition "other_test_suites_did_not_fail" is tested by asserting that no log files exist that fit the "*-test-fail.log" pattern while excluding the log file of the "testmthread" test suite (testmthread-test-fail.log).
        # TODO: Revert this change once that issue is fixed.
      - name: Run tests
        run: |
          mkdir ci-logs
          nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run '(cabal test --test-log="$(pwd)/ci-logs/\$test-suite-test-\$result.log" || grep "testmthread: Contains an unsupported closure type (whose implementation is missing)" ci-logs/testmthread-test-fail.log) && (! find ci-logs ! -name testmthread-test-fail.log -name "*-test-fail.log"|grep .)'

      # Print output of failed test cases
      - name: Print output of failed tests
        if: failure()
        run: nix-shell --argstr ghcVersion ${{ matrix.ghc }} --argstr ccVersion ${{ matrix.cc }} --run 'tail -v -n +1 ci-logs/*-test-fail.log'