Set the typedefinitionProvider capability if it has a handler

The capability can either be a static bool, or a dynamic option given
the specific file it applies to.  If the server explicitly sets the
option to one of those in its Config we use it, else set it to
statically True if there is a handler for the type definition request.

Author: alanz

src/Language/Haskell/LSP/Core.hs

@@ -600,6 +600,12 @@ initializeRequestHandler' (_configHandler,dispatcherProc) mHandler tvarCtx req@(
           supported (Just _) = Just True
           supported Nothing   = Nothing
 
+          -- If a dynamic setting is provided use it, else set a
+          -- static True if there is a handler.
+          static (Just d) _ = Just d
+          static _ (Just _) = Just (J.GotoOptionsStatic True)
+          static _ Nothing  = Nothing
+
           sync = case textDocumentSync o of
                   Just x -> Just (J.TDSOptions x)
                   Nothing -> Nothing
@@ -618,7 +624,7 @@ initializeRequestHandler' (_configHandler,dispatcherProc) mHandler tvarCtx req@(
               , J._completionProvider               = completionProvider o
               , J._signatureHelpProvider            = signatureHelpProvider o
               , J._definitionProvider               = supported (definitionHandler h)
-              , J._typeDefinitionProvider           = typeDefinitionProvider o
+              , J._typeDefinitionProvider           = static (typeDefinitionProvider o) (typeDefinitionHandler h)
               , J._implementationProvider           = implementationProvider o
               , J._referencesProvider               = supported (referencesHandler h)
               , J._documentHighlightProvider        = supported (documentHighlightHandler h)