Make use of the new Cabal testing interface

Also, take a chance to update the .cabal file

Setup.hs

@@ -1,8 +1,2 @@
 import Distribution.Simple
-import System.Process (rawSystem)
-import System.Exit (ExitCode(..))
-import System.FilePath ((</>))
-main = defaultMainWithHooks $ simpleUserHooks { runTests = \args _ _ _ -> do
-    ExitSuccess <- rawSystem "runhaskell" (("Test" </> "Runner.hs") : args)
-    return ()
-                                              }
+main = defaultMain

haskell-src-exts.cabal

@@ -30,7 +30,7 @@ Homepage:               https://github.com/haskell-suite/haskell-src-exts
 Stability:              Stable
 Tested-with:            GHC==6.10.2, GHC==6.10.4, GHC==6.12.3, GHC==7.0.2
 Build-Type:             Custom
-Cabal-Version:          >= 1.6
+Cabal-Version:          >= 1.10
 
 Extra-Source-Files:
 			CHANGELOG
@@ -115,6 +115,7 @@ Extra-Source-Files:
 Flag base4
 
 Library
+  Default-language:     Haskell98
   Build-Tools:          happy >= 1.17
   Build-Depends:        array >= 0.1, pretty >= 1.0, cpphs >= 1.3
   if flag(base4)
@@ -154,3 +155,17 @@ Library
 Source-Repository head
         Type:           git
         Location:       https://github.com/haskell-suite/haskell-src-exts.git
+
+Test-Suite test
+  type:                exitcode-stdio-1.0
+  main-is:             Test/Runner.hs
+  GHC-Options:         -threaded
+  Default-language:    Haskell2010
+  Build-depends:       base < 5,
+                       haskell-src-exts,
+                       smallcheck >= 1.0,
+                       tasty,
+                       tasty-smallcheck,
+                       tasty-hunit,
+                       filepath,
+                       directory