Reduce default number of quickcheck tests in dejafu-tests

dejafu-tests/Main.hs

@@ -1,15 +1,30 @@
 module Main where
 
-import Test.Framework (Test, defaultMain, testGroup)
+import Data.Maybe (fromMaybe)
+import System.Environment (getArgs)
+import qualified Test.Framework as T
 
 import Cases
 import Examples
 
 main :: IO ()
-main = defaultMain allTests
+main = do
+  opts <- setDefaults <$> (T.interpretArgsOrExit =<< getArgs)
+  T.defaultMainWithOpts allTests opts
 
-allTests :: [Test]
-allTests = map (uncurry testGroup)
+allTests :: [T.Test]
+allTests = map (uncurry T.testGroup)
   [ ("Test Cases", testCases)
   , ("Examples",   testExamples)
   ]
+
+-- | Reduce the default number of quickcheck runs.
+setDefaults :: T.RunnerOptions -> T.RunnerOptions
+setDefaults opts = opts { T.ropt_test_options = set (T.ropt_test_options opts) } where
+  set (Just opts) = Just (set' opts)
+  set Nothing = Just (set' (T.TestOptions Nothing Nothing Nothing Nothing Nothing Nothing))
+
+  set' opts = opts
+    { T.topt_maximum_generated_tests = Just . fromMaybe 25 $
+        T.topt_maximum_generated_tests opts
+    }