travis: switch CI builds from Stack to cabal-install

 - Add license file.
 - Add Setup.lhs file.
 - Drop obsolete dependency on pretty-show.

.travis.yml

@@ -1,21 +1,85 @@
-# .travis.yml
-
-language: haskell
+# This file has been generated -- see https://github.com/hvr/multi-ghc-travis
+language: c
 sudo: false
 
 cache:
   directories:
-    - $HOME/.stack
+    - $HOME/.cabsnap
+    - $HOME/.cabal/packages
+
+before_cache:
+  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/build-reports.log
+  - rm -fv $HOME/.cabal/packages/hackage.haskell.org/00-index.tar
+
+matrix:
+  include:
+    - env: CABALVER=1.22 GHCVER=7.10.1
+      compiler: ": #GHC 7.10.1"
+      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.1], sources: [hvr-ghc]}}
+    - env: CABALVER=1.22 GHCVER=7.10.2
+      compiler: ": #GHC 7.10.2"
+      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.2], sources: [hvr-ghc]}}
+    - env: CABALVER=1.22 GHCVER=7.10.3
+      compiler: ": #GHC 7.10.3"
+      addons: {apt: {packages: [cabal-install-1.22,ghc-7.10.3], sources: [hvr-ghc]}}
+    - env: CABALVER=1.24 GHCVER=8.0.1
+      compiler: ": #GHC 8.0.1"
+      addons: {apt: {packages: [cabal-install-1.24,ghc-8.0.1], sources: [hvr-ghc]}}
 
 before_install:
-  - curl -L https://github.com/commercialhaskell/stack/releases/download/v1.1.2/stack-1.1.2-linux-x86_64.tar.gz | tar xfz -
-  - install -m 555 -D stack-1.1.2-linux-x86_64/stack $HOME/.local/bin/stack
-  - export PATH=$HOME/.local/bin:$PATH
-  - stack setup
+ - unset CC
+ - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH
 
 install:
-  - stack build hscolour --copy-bins
-  - stack build --only-snapshot --flag=nix-paths:allow-relative-paths
+ - 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 $HOME/.cabsnap/;
+   fi
+
+# Here starts the actual work to be performed for the package under test;
+# any command which exits with a non-zero exit code causes the build to fail.
 script:
-  - stack build --pedantic --test --haddock
+ - if [ -f configure.ac ]; then autoreconf -i; fi
+ - cabal configure --enable-tests --enable-benchmarks -v2  # -v2 provides useful information for debugging
+ - cabal build   # this builds all libraries and executables (including tests/benchmarks)
+ - cabal test
+ - cabal check
+ - cabal sdist   # tests that a source-distribution can be generated
+
+# Check that the resulting source distribution can be built & installed.
+# If there are no other `.tar.gz` files in `dist`, this can be even simpler:
+# `cabal install --force-reinstalls dist/*-*.tar.gz`
+ - SRC_TGZ=$(cabal info . | awk '{print $2;exit}').tar.gz &&
+   (cd dist && cabal install --force-reinstalls "$SRC_TGZ")
+
+# EOF

LICENSE

@@ -0,0 +1,30 @@
+Redistribution and use in source and binary forms, with or
+without modification, are permitted provided that the
+following conditions are met:
+
+  * Redistributions of source code must retain the above
+    copyright notice, this list of conditions and the
+    following disclaimer.
+
+  * Redistributions in binary form must reproduce the above
+    copyright notice, this list of conditions and the
+    following disclaimer in the documentation and/or other
+    materials provided with the distribution.
+
+  * The names of its contributors may not be used to endorse
+    or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Setup.lhs

@@ -0,0 +1,40 @@
+#! /usr/bin/env runhaskell
+
+> module Main ( main ) where
+>
+> import Data.Char
+> import Data.Maybe
+> import Distribution.PackageDescription
+> import Distribution.Simple
+> import Distribution.Simple.LocalBuildInfo
+> import Distribution.Simple.Program
+> import Distribution.Simple.Setup
+>
+> main :: IO ()
+> main = defaultMainWithHooks simpleUserHooks
+>        { hookedPrograms = map simpleProgram programs
+>        , confHook = configure
+>        }
+>
+> programs :: [String]
+> programs = ["nix-instantiate", "nix-build", "nix-env", "nix-store"]
+>
+> configure :: (GenericPackageDescription, HookedBuildInfo) -> ConfigFlags -> IO LocalBuildInfo
+> configure (gpd, hbi) flags = do
+>   lbi' <- confHook simpleUserHooks (gpd, hbi) flags
+>   let paths = map (\p -> (p, maybe p programPath (lookupProgram (simpleProgram p) (withPrograms lbi)))) programs
+>       descr = localPkgDescr lbi'
+>       lib = fromJust (library descr)
+>       libbi = libBuildInfo lib
+>       lbi = lbi' { localPkgDescr = descr
+>                    { library = Just (lib { libBuildInfo = libbi { cppOptions = cppOptions libbi ++ map fmtCppArg paths } })
+>                    }
+>                  }
+>   return lbi
+>
+> fmtCppArg :: (String, FilePath) -> String
+> fmtCppArg (prg, path) = "-DPATH_TO_" ++ map mangle prg ++ "=" ++ show path
+>   where
+>     mangle :: Char -> Char
+>     mangle '-' = '_'
+>     mangle c = toUpper c

cabal2nix.cabal

@@ -11,6 +11,8 @@ homepage:       https://github.com/nixos/cabal2nix#readme
 bug-reports:    https://github.com/nixos/cabal2nix/issues
 maintainer:     Peter Simons <simons@cryp.to>
 license:        BSD3
+license-file:   LICENSE
+tested-with:    GHC > 7.10 && < 8.1
 build-type:     Simple
 cabal-version:  >= 1.10
 
@@ -38,7 +40,6 @@ library
     , lens
     , optparse-applicative
     , pretty >= 1.1.2
-    , pretty-show
     , process
     , SHA
     , split
@@ -65,6 +66,38 @@ library
       Paths_cabal2nix
   default-language: Haskell2010
 
+executable cabal2nix
+  main-is: Main.hs
+  hs-source-dirs:
+      cabal2nix
+  ghc-options: -Wall
+  build-depends:
+      aeson
+    , ansi-wl-pprint
+    , base < 5
+    , bytestring
+    , Cabal > 1.24
+    , containers
+    , deepseq >= 1.4
+    , directory
+    , distribution-nixpkgs
+    , filepath
+    , hackage-db
+    , language-nix
+    , lens
+    , optparse-applicative
+    , pretty >= 1.1.2
+    , process
+    , SHA
+    , split
+    , text
+    , transformers
+    , yaml
+    , cabal2nix
+  other-modules:
+      Paths_cabal2nix
+  default-language: Haskell2010
+
 executable hackage2nix
   main-is: Main.hs
   hs-source-dirs:
@@ -86,7 +119,6 @@ executable hackage2nix
     , lens
     , optparse-applicative
     , pretty >= 1.1.2
-    , pretty-show
     , process
     , SHA
     , split

cabal2nix/Main.hs

@@ -153,7 +153,6 @@ main = bracket (return ()) (\() -> hFlush stdout >> hFlush stderr) $ \() -> do
               , text "  if pkgs.lib.inNixShell then drv.env else drv"
               ]
 
-  -- putStrLn $ ppShow deriv
   print (if optNixShellOutput then shell else pPrint deriv)
 
 readFlagList :: [String] -> FlagAssignment

package.yaml

@@ -4,8 +4,10 @@ synopsis:               Convert Cabal files into Nix build instructions.
 description:            Convert Cabal files into Nix build instructions.
 maintainer:             Peter Simons <simons@cryp.to>
 license:                BSD3
+license-file:           LICENSE
 github:                 nixos/cabal2nix
 category:               Distribution
+tested-with:            GHC > 7.10 && < 8.1
 
 ghc-options:            -Wall
 
@@ -25,7 +27,6 @@ dependencies:
   - lens
   - optparse-applicative
   - pretty >= 1.1.2
-  - pretty-show
   - process
   - SHA
   - split