LSP implementation returns void for rename (although backend request works)

[mickaelistria]

I'm sending a Language Server Protocol "Rename" request. I can see via telemetry events that this get processed fine (I'm renaming i variable to blah), but the result is empty:

Here is what I receive from OmniSharp-node. The 3rd message shows the the replace works internally, last one shows it's not returned.

jsonrpc":"2.0","method":"telemetry/event","params":{"clientId":"client1","command":"/rename","request":{"FileName":"/home/mistria/git/3dLocalizer/test.cs","Line":9,"Column":8,"RenameTo":"blah"},"silent":false,"sequence":"__request3","time":"2016-08-29T08:50:40.411Z"}}

{"jsonrpc":"2.0","method":"telemetry/event","params":{"Event":"log","Body":{"LogLevel":"INFORMATION","Name":"OmniSharp.Middleware.LoggingMiddleware","Message":"/rename: 200 899ms"},"Seq":21,"Type":"event"}}

{"jsonrpc":"2.0","method":"telemetry/event","params":{"command":"/rename","response":{"Changes":[{"FileName":"/home/mistria/git/3dLocalizer/test.cs","Buffer":"using System;\npublic class HelloWorld\n{\n    public static void Afficher()\n    {\n   \t\tint blah = 0;\n        Console.WriteLine(\"Hello world !\");\n        Console.ReadLine();\n        \n        blah++;\n        int a = blah / 3; \n    }\n}\n","Changes":null}],"ErrorMessage":null},"clientId":"client1","request":{"FileName":"/home/mistria/git/3dLocalizer/test.cs","Line":9,"Column":8,"RenameTo":"blah"},"sequence":"__request3","time":"2016-08-29T08:50:41.313Z","silent":false,"failed":false,"responseTime":902}}

{"jsonrpc":"2.0","id":"1","result":{"changes":{"file:///home/mistria/git/3dLocalizer/test.cs":[]}}}Content-Length: 141