env:
  - CABALVER=1.18 GHCVER=7.6.3
  - CABALVER=1.18 GHCVER=7.8.3
  - CABALVER=1.22 GHCVER=7.10.1

before_install:
  - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
  - travis_retry sudo apt-get update
  - travis_retry sudo apt-get -qq -y install cabal-install-$CABALVER ghc-$GHCVER
  - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH

install:
  - cabal --version
  - echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"
  - travis_retry cabal update
  - |
    if [ $GHCVER = "head" ] || [ ${GHCVER%.*} = "7.8" ]  || [ ${GHCVER%.*} = "7.10" ]; then
      travis_retry sudo apt-get install happy-1.19.4 alex-3.1.3
      export PATH=/opt/alex/3.1.3/bin:/opt/happy/1.19.4/bin:$PATH
    else
      travis_retry sudo apt-get install happy alex
    fi
  
  - cabal install --dependencies-only --enable-tests

script:
  - cabal configure --enable-tests
  - cabal build
  - cabal test
  - cabal check || true
  - cabal sdist

# The following scriptlet checks that the resulting source distribution can be built & installed
  - export SRC_TGZ=$(cabal info . | awk '{print $2 ".tar.gz";exit}') ;
    cd dist/;
    if [ -f "$SRC_TGZ" ]; then
       cabal install --force-reinstalls "$SRC_TGZ";
    else
       echo "expected '$SRC_TGZ' not found";
       exit 1;
    fi