Fix a bug in onlyJsonObjects that made it fail if there was no

content-type.

src/Servant/QuickCheck/Internal/Predicates.hs

@@ -84,15 +84,13 @@ notLongerThan maxAllowed
 -- /Since 0.0.0.0/
 onlyJsonObjects :: ResponsePredicate
 onlyJsonObjects
-  = ResponsePredicate (\resp -> case go resp of
+  = ResponsePredicate (\resp -> do
-      Nothing -> throw $ PredicateFailure "onlyJsonObjects" Nothing resp
+    case lookup "content-type" (first foldedCase <$> responseHeaders resp) of
-      Just () -> return ())
+      Nothing    -> return ()
-    where
+      Just ctype -> when ("application/json" `SBS.isPrefixOf` ctype) $ do
-      go r = do
+        case (decode (responseBody resp) :: Maybe Object) of
-        ctyp <- lookup "content-type" (first foldedCase <$> responseHeaders r)
+          Nothing -> throw $ PredicateFailure "onlyJsonObjects" Nothing resp
-        when ("application/json" `SBS.isPrefixOf` ctyp) $ do
+          Just _  -> return ())
-          (_ :: Object) <- decode (responseBody r)
-          return ()
 
 -- | __Optional__
 --