Deprecate internal error generation functions

The functions generating errors in the executor should be changed anyway
when we provide better error messages from the executor, with the error
location and response path. So public definitions of these functions are
deprecated now and they are replaced by more generic functions in the
executor code.

src/Language/GraphQL/Execute.hs

@@ -11,9 +11,10 @@ import Data.Text (Text)
 import Language.GraphQL.AST.Document (Document, Name)
 import Language.GraphQL.Execute.Coerce
 import Language.GraphQL.Execute.Execution
+import Language.GraphQL.Execute.Internal
 import qualified Language.GraphQL.Execute.Transform as Transform
 import qualified Language.GraphQL.Execute.Subscribe as Subscribe
-import Language.GraphQL.Error
+import Language.GraphQL.Error (ResponseEventStream, Response, runCollectErrs)
 import qualified Language.GraphQL.Type.Definition as Definition
 import qualified Language.GraphQL.Type.Out as Out
 import Language.GraphQL.Type.Schema
@@ -32,10 +33,7 @@ execute :: (MonadCatch m, VariableValue a, Serialize b)
     -> m (Either (ResponseEventStream m b) (Response b))
 execute schema' operationName subs document =
     case Transform.document schema' operationName subs document of
-        Left queryError -> pure
-            $ Right
-            $ singleError
-            $ Transform.queryError queryError
+        Left queryError -> pure $ singleError $ Transform.queryError queryError
         Right transformed -> executeRequest transformed
 
 executeRequest :: (MonadCatch m, Serialize a)
@@ -47,7 +45,7 @@ executeRequest (Transform.Document types' rootObjectType operation)
     | (Transform.Mutation _ fields) <- operation =
         Right <$> executeOperation types' rootObjectType fields
     | (Transform.Subscription _ fields) <- operation
-        = either (Right . singleError) Left
+        = either singleError Left
         <$> Subscribe.subscribe types' rootObjectType fields
 
 -- This is actually executeMutation, but we don't distinguish between queries