Make findCommand tests run just for MongoDB 3.2 or superior

Database/MongoDB/Query.hs

@@ -1045,7 +1045,7 @@ findCommand Query{..} = do
       , "hint"        =: hint
       , "skip"        =: toInt32 skip
       ]
-      ++ mconcat -- optional fields
+      ++ mconcat -- optional fields. They should not be present if set to 0 and mongo will use defaults
          [ "batchSize" =? toMaybe (/= 0) toInt32 batchSize
          , "limit"     =? toMaybe (/= 0) toInt32 limit
          ]

test/QuerySpec.hs

@@ -43,13 +43,20 @@ insertDuplicateWith testInsert = do
                               ]
   return ()
 
-insertUsers :: ActionWith () -> IO ()
-insertUsers doTest = do
-  db $ insertAll_ "users" [ ["_id" =: "jane", "joined" =: parseDate "2011-03-02", "likes" =: ["golf", "racquetball"]]
+insertUsers :: IO ()
+insertUsers = db $
+  insertAll_ "users" [ ["_id" =: "jane", "joined" =: parseDate "2011-03-02", "likes" =: ["golf", "racquetball"]]
                      , ["_id" =: "joe", "joined" =: parseDate "2012-07-02", "likes" =: ["tennis", "golf", "swimming"]]
                      , ["_id" =: "jill", "joined" =: parseDate "2013-11-17", "likes" =: ["cricket", "golf"]]
                      ]
-  doTest ()
+
+pendingIfMongoVersion :: ((Integer, Integer) -> Bool) -> SpecWith () -> Spec
+pendingIfMongoVersion invalidVersion = before $ do
+  version <- db $ extractVersion . T.splitOn "." . at "version" <$> runCommand1 "buildinfo"
+  when (invalidVersion version) $ pendingWith "This test does not run in the current database version"
+  where
+    extractVersion (major:minor:_) = (read $ T.unpack major, read $ T.unpack minor)
+    extractVersion _               = error "Invalid version specification"
 
 bigDocument :: Document
 bigDocument = (flip map) [1..10000] $ \i -> (fromString $ "team" ++ (show i)) =: ("team " ++ (show i) ++ " name")
@@ -436,14 +443,17 @@ spec = around withCleanDatabase $ do
       collections <- db $ allCollections
       liftIO $ (L.sort collections) `shouldContain` ["team1", "team2", "team3"]
 
-  describe "aggregate" $ around insertUsers $
+  describe "aggregate" $ before_ insertUsers $
     it "aggregates to normalize and sort documents" $ do
       result <- db $ aggregate "users" [ ["$project" =: ["name" =: ["$toUpper" =: "$_id"], "_id" =: 0]]
                                        , ["$sort" =: ["name" =: 1]]
                                        ]
       result `shouldBe` [["name" =: "JANE"], ["name" =: "JILL"], ["name" =: "JOE"]]
 
-  describe "findCommand" $ around insertUsers $ do
+  -- This feature was introduced in MongoDB version 3.2
+  -- https://docs.mongodb.com/manual/reference/command/find/
+  describe "findCommand" $ pendingIfMongoVersion (< (3,2)) $
+    context "when mongo version is 3.2 or superior" $ before insertUsers $ do
       it "fetches all the records" $ do
           result <- db $ rest =<< findCommand (select [] "users")
           length result `shouldBe` 3