Some minor fixups for compilation

hnix.cabal

@@ -2,7 +2,7 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 429fc2370bb078161c283b1238eb797ca1c03c46e4c1a2f68ac80937a901bb79
+-- hash: 2a22f1191905e2b66f2d356247a272e923144902c5ad6026fe72d137f8127a77
 
 name:           hnix
 version:        0.5.0
@@ -135,6 +135,7 @@ test-suite hnix-tests
       NixLanguageTests
       ParserTests
       PrettyTests
+      TestCommon
       Paths_hnix
   hs-source-dirs:
       tests

tests/NixLanguageTests.hs

@@ -23,7 +23,6 @@ import           Nix.Utils
 import           Nix.Stack
 import           Nix.Value
 import           Nix.XML
-import           System.Directory
 import           System.Environment
 import           System.FilePath
 import           System.FilePath.Glob (compile, globDir1)
@@ -128,7 +127,7 @@ assertEval files = catch go $ \case
 
 assertEvalFail :: FilePath -> Assertion
 assertEvalFail file = catch ?? (\(_ :: SomeException) -> return ()) $ do
-  evalResult <- printNix <$> nixEvalFile file
+  evalResult <- printNix <$> hnixEvalFile file
   evalResult `seq` assertFailure $
       file ++ " should not evaluate.\nThe evaluation result was `"
            ++ evalResult ++ "`."

tests/TestCommon.hs

@@ -1,16 +1,16 @@
 module TestCommon where
 
-import           Nix
-import           Nix.Monad
-import           Nix.Monad.Instance
-import           Nix.Parser
-import           Nix.Pretty
-import           System.Directory
-import           System.Environment
-import           System.IO
-import           System.Posix.Temp
-import           System.Process
-import           Test.Tasty.HUnit
+import Nix
+import Nix.Monad.Instance
+import Nix.Parser
+import Nix.Pretty
+import Nix.Value
+import System.Environment
+import System.IO
+import System.Posix.Files
+import System.Posix.Temp
+import System.Process
+import Test.Tasty.HUnit
 
 hnixEvalFile :: FilePath -> IO (NValueNF (Lazy IO))
 hnixEvalFile file =  do
@@ -23,8 +23,7 @@ hnixEvalFile file =  do
         evalLoc (Just file) expression
 
 hnixEvalString :: String -> IO (NValueNF (Lazy IO))
-hnixEvalString expr =  do
-  case parseNixString expr of
+hnixEvalString expr = case parseNixString expr of
     Failure err        ->
         error $ "Parsing failed for expressien `" ++ expr ++ "`.\n" ++ show err
     Success expression -> eval Nothing expression
@@ -35,13 +34,11 @@ nixEvalString expr = do
   hPutStr h expr
   hClose h
   res <- nixEvalFile fp
-  removeFile fp
+  removeLink fp
   return res
 
 nixEvalFile :: FilePath -> IO String
-nixEvalFile fp = do
-  readProcess "nix-instantiate" ["--eval", fp] ""
-
+nixEvalFile fp = readProcess "nix-instantiate" ["--eval", fp] ""
 
 assertEvalMatchesNix :: String -> Assertion
 assertEvalMatchesNix expr = do