set -e

case $BUILD in

stack)

mkdir -p ~/.local/bin;

if [ `uname` = "Darwin" ]; then

curl -kL https://www.stackage.org/stack/osx-x86_64 | tar xz --strip-components=1 --include '*/stack' -C ~/.local/bin;

else

curl -L https://www.stackage.org/stack/linux-x86_64 | tar xz --wildcards --strip-components=1 -C ~/.local/bin '*/stack';

fi

stack --no-terminal setup

stack --no-terminal test --only-dependencies

;;

cabal)

if [ -n "$STACKAGESNAPSHOT" ]; then

curl -sL https://www.stackage.org/$STACKAGESNAPSHOT/cabal.config | sed 's/constraints:/preferences:/' | grep -v installed > cabal.config

head cabal.config

fi

cabal --version

echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"

if [ -f $HOME/.cabal/packages/hackage.haskell.org/00-index.tar.gz ]; then

zcat $HOME/.cabal/packages/hackage.haskell.org/00-index.tar.gz > $HOME/.cabal/packages/hackage.haskell.org/00-index.tar

fi

cabal update -v

sed -i 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config

cabal install --only-dependencies --enable-tests --enable-benchmarks --dry -v > installplan.txt

sed -i -e '1,/^Resolving /d' installplan.txt; cat installplan.txt

# check whether current requested install-plan matches cached package-db snapshot

if diff -u installplan.txt $HOME/.cabsnap/installplan.txt; then

echo "cabal build-cache HIT";

rm -rfv .ghc;

cp -a $HOME/.cabsnap/ghc $HOME/.ghc;

cp -a $HOME/.cabsnap/lib $HOME/.cabsnap/share $HOME/.cabsnap/bin $HOME/.cabal/;

else

echo "cabal build-cache MISS";

rm -rf $HOME/.cabsnap;

mkdir -p $HOME/.ghc $HOME/.cabal/lib $HOME/.cabal/share $HOME/.cabal/bin;

cabal install --only-dependencies --enable-tests --enable-benchmarks;

fi

# snapshot package-db on cache miss

if [ ! -d $HOME/.cabsnap ]; then

echo "snapshotting package-db to build-cache";

mkdir $HOME/.cabsnap;

cp -a $HOME/.ghc $HOME/.cabsnap/ghc;

cp -a $HOME/.cabal/lib $HOME/.cabal/share $HOME/.cabal/bin installplan.txt $HOME/.cabsnap/;

fi

;;