Add sanity checks for wrappers to CI

.travis.yml

@@ -6,6 +6,7 @@
 #
 # version: 0.3
 #
+# Additional changes included a shellcheck step
 language: c
 dist: xenial
 
@@ -86,6 +87,10 @@ install:
 # 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:
+  # Sanity checks for wrapper scripts
+  - shellcheck wrappers/cabal
+  - (cd wrappers && ${HC} -hide-all-packages -package base -package directory -package process -Wall -Werror cabal.hs -o CabalWrapper)
+
   # test that source-distributions can be generated
   - ${CABAL} new-sdist all
   - mv dist-newstyle/sdist/*.tar.gz ${DISTDIR}/
@@ -114,6 +119,3 @@ script:
 
   # Build without installed constraints for packages in global-db
   - rm -f cabal.project.local; ${CABAL} new-build -w ${HC} --disable-tests --disable-benchmarks all
-
-# REGENDATA ["hie-bios.cabal"]
-# EOF

appveyor.yml

@@ -10,8 +10,10 @@ install:
   - choco install -y haskell-stack
   - choco install -y cabal
   - choco install ghc --version %GHCVER%
+  - choco install -y shellcheck
   - refreshenv
   - "set PATH=C:\\ProgramData\\chocolatey\\lib\\ghc\\tools\\ghc-%GHCVER%\\bin;C:\\msys64\\mingw64\\bin;C:\\msys64\\usr\\bin;%PATH%"
+  - shellcheck --version
   - stack --version
   - cabal --version
   - ghc --version
@@ -30,6 +32,10 @@ build_script:
 
 before_test:
   - cabal v2-build --enable-tests -w ghc-%GHCVER%.exe tests
+  # sanity check the wrappers
+  - shellcheck wrappers/cabal
+  - ghc -hide-all-packages -package base -package directory -package process -Wall -Werror wrappers/cabal.hs -o CabalWrapper -odir %TMP%
+
 
 test_script:
   - cabal v2-test -w ghc-%GHCVER%.exe

wrappers/cabal

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 function out(){
-  echo "$1" >> $HIE_BIOS_OUTPUT
+  echo "$1" >> "$HIE_BIOS_OUTPUT"
 }
 
 if [ "$1" == "--interactive" ]; then

wrappers/cabal.hs

@@ -1,11 +1,12 @@
 module Main (main) where
 
 import System.Directory (getCurrentDirectory)
-import System.Environment (getArgs, getEnv, lookupEnv)
+import System.Environment (getArgs, getEnv)
 import System.Exit (exitWith)
 import System.Process (spawnProcess, waitForProcess)
 import System.IO (openFile, hClose, hPutStrLn, IOMode(..))
 
+main :: IO ()
 main = do
   args <- getArgs
   output_file <- getEnv "HIE_BIOS_OUTPUT"