test: Set nonzero exitcode when tests fail

* Create a single list of quickcheck properties
* Test the result of the quickcehck run
* Exit with appropriate status code

tests/DListProperties.hs

@@ -20,7 +20,7 @@
 --------------------------------------------------------------------------------
 
 -- | QuickCheck property tests for DList.
-module DListProperties (test) where
+module DListProperties (properties) where
 
 --------------------------------------------------------------------------------
 
@@ -183,6 +183,3 @@ properties =
     ("Semigroup stimes", property prop_Semigroup_stimes)
 #endif
   ]
-
-test :: IO ()
-test = quickCheckLabeledProperties properties

tests/DNonEmptyProperties.hs

@@ -8,7 +8,7 @@
 --------------------------------------------------------------------------------
 
 -- | QuickCheck property tests for DNonEmpty.
-module DNonEmptyProperties (test) where
+module DNonEmptyProperties (properties) where
 
 --------------------------------------------------------------------------------
 
@@ -104,6 +104,3 @@ properties =
     ("fromList", property prop_fromList),
     ("Semigroup <>", property prop_Semigroup_append)
   ]
-
-test :: IO ()
-test = quickCheckLabeledProperties properties

tests/Main.hs

@@ -18,14 +18,20 @@ import qualified DListProperties
 import qualified DNonEmptyProperties
 #endif
 import qualified OverloadedStrings
+import QuickCheckUtil (quickCheckLabeledProperties)
+import Control.Monad (unless)
+import Test.QuickCheck (isSuccess)
+import System.Exit (exitFailure)
 
 --------------------------------------------------------------------------------
 
 main :: IO ()
 main = do
-  DListProperties.test
--- CPP: GHC >= 8 for DNonEmpty
+  OverloadedStrings.test
+  result <- quickCheckLabeledProperties $
+    DListProperties.properties
+  -- CPP: GHC >= 8 for DNonEmpty
 #if __GLASGOW_HASKELL__ >= 800
-  DNonEmptyProperties.test
+    ++ DNonEmptyProperties.properties
 #endif
-  OverloadedStrings.test
+  unless (isSuccess result) exitFailure

tests/QuickCheckUtil.hs

@@ -37,8 +37,8 @@ eqOn c f g x = c x ==> f x == g x
 
 --------------------------------------------------------------------------------
 
-quickCheckLabeledProperties :: [(String, Property)] -> IO ()
-quickCheckLabeledProperties = quickCheck . conjoin . map (uncurry label)
+quickCheckLabeledProperties :: [(String, Property)] -> IO Result
+quickCheckLabeledProperties = quickCheckResult . conjoin . map (uncurry label)
 
 --------------------------------------------------------------------------------