Cabal after build command (Haskell build system)

Question

Is it possible to tell Cabal to run some command after building the application?

I want for example to generate with a script some .hs files and after building to copy some other files to dist/build/app directory.

Answer 1

Yes. Take a look at postInst and related types/operations.

Distribution.Simple.UserHooks

Here's a quick example, you can hoogle the relevant operations to figure out more. This executes the various .sh scripts, copies files etc. AFTER the cabal build. absoluteInstallDirs tells you where cabal is putting the other files, should you need it.

Hope this helps!

import Distribution.Simple
import Distribution.Simple.LocalBuildInfo
import System.Process
import System.Exit

main = defaultMainWithHooks fixpointHooks

fixpointHooks  = simpleUserHooks { postInst = buildAndCopyFixpoint } 

buildAndCopyFixpoint _ _ pkg lbi 
  = do putStrLn $ "Post Install: " ++ show binDir -- , libDir)
       executeShellCommand "./configure"
       executeShellCommand "./build.sh"
       executeShellCommand $ "chmod a+x external/fixpoint/fixpoint.native "
       executeShellCommand $ "cp external/fixpoint/fixpoint.native " ++ binDir
       executeShellCommand $ "cp external/z3/lib/libz3.* " ++ binDir
  where 
    allDirs     = absoluteInstallDirs pkg lbi NoCopyDest
    binDir      = bindir allDirs ++ "/"

executeShellCommand cmd   = putStrLn ("EXEC: " ++ cmd) >> system cmd >>= check
  where 
    check (ExitSuccess)   = return ()
    check (ExitFailure n) = error $ "cmd: " ++ cmd ++ " failure code " ++ show n
fixpointHooks  = simpleUserHooks { postInst = buildAndCopyFixpoint }