Add failing test for runGhcModT

test/MonadSpec.hs

@@ -1,6 +1,9 @@
+{-# LANGUAGE ScopedTypeVariables #-}
 module MonadSpec where
 
 import Test.Hspec
+import Dir
+import Control.Applicative
 import Control.Monad.Error.Class
 import Language.Haskell.GhcMod.Types
 import Language.Haskell.GhcMod.Monad
@@ -17,3 +20,8 @@ spec = do
                          return "hello"
                      `catchError` (const $ fail "oh noes")
              a `shouldBe` (Left $ GMEString "oh noes")
+
+    describe "runGhcModT" $
+        it "complains if the cabal file fails to parse while a sandbox is present" $ withDirectory_ "test/data/broken-cabal" $ do
+          (a,_) <- runGhcModT defaultOptions (gmCradle <$> ask)
+          a `shouldSatisfy` (\(Left _) -> True)

test/data/broken-cabal/cabal.sandbox.config.in

@@ -0,0 +1,25 @@
+-- This is a Cabal package environment file.
+-- THIS FILE IS AUTO-GENERATED. DO NOT EDIT DIRECTLY.
+-- Please create a 'cabal.config' file in the same directory
+-- if you want to change the default settings for this sandbox.
+
+
+local-repo: @CWD@/test/data/broken-cabal/.cabal-sandbox/packages
+logs-dir: @CWD@/test/data/broken-cabal/.cabal-sandbox/logs
+world-file: @CWD@/test/data/broken-cabal/.cabal-sandbox/world
+user-install: False
+package-db: @CWD@/test/data/broken-cabal/.cabal-sandbox/x86_64-linux-ghc-7.8.3-packages.conf.d
+build-summary: @CWD@/test/data/broken-cabal/.cabal-sandbox/logs/build.log
+
+install-dirs
+  prefix: @CWD@/test/data/broken-cabal/.cabal-sandbox
+  bindir: $prefix/bin
+  libdir: $prefix/lib
+  libsubdir: $arch-$os-$compiler/$pkgid
+  libexecdir: $prefix/libexec
+  datadir: $prefix/share
+  datasubdir: $arch-$os-$compiler/$pkgid
+  docdir: $datadir/doc/$arch-$os-$compiler/$pkgid
+  htmldir: $docdir/html
+  haddockdir: $htmldir
+  sysconfdir: $prefix/etc