Fix JSONSchema test assertion to correctly handle the case of invalid…

… namespace.

hydra-node/test/Hydra/JSONSchema.hs

@@ -57,7 +57,13 @@ prop_validateToJSON specFile namespace inputFile =
         forAllBlind (vectorOf 1000 arbitrary) $
           \(a :: [a]) -> monadicIO $ do
             specs <- run $ Aeson.decodeFileStrict specFile
-            let unknownConstructors = Map.keys $ Map.filter (== 0) $ classify specs a
+            let knownKeys = classify specs a
+            let unknownConstructors = Map.keys $ Map.filter (== 0) knownKeys
+
+            when (null knownKeys) $ do
+              monitor $ counterexample $ "No keys found in given namespace: " <> toString namespace
+              assert False
+
             unless (null unknownConstructors) $ do
               let commaSeparated = intercalate ", " (toString <$> unknownConstructors)
               monitor $ counterexample $ "Unimplemented constructors present in specification: " <> commaSeparated
@@ -79,7 +85,7 @@ prop_validateToJSON specFile namespace inputFile =
               mempty
 
         countMatch (strawmanGetConstr -> tag) =
-          Map.alter (Just . maybe 1 (+ 1)) tag
+          Map.adjust (+ 1) tag
      in foldr countMatch knownKeys
   classify _ =
     error $ "Invalid specification file. Does not decode to an object: " <> show specFile