- - cabal --version
- - echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"
- - travis_retry cabal update
- - sed -i 's/^jobs:/-- jobs:/' ${HOME}/.cabal/config # The container environment reports 16 cores
- - cabal install --only-dependencies --enable-tests --enable-benchmarks
+ - cabal --version
+ - echo "$(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
+ - travis_retry 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