diff --git a/haskell-lsp-types.cabal b/haskell-lsp-types.cabal
--- a/haskell-lsp-types.cabal
+++ b/haskell-lsp-types.cabal
@@ -1,5 +1,5 @@
 name:                haskell-lsp-types
-version:             0.12.0.0
+version:             0.12.1.0
 synopsis:            Haskell library for the Microsoft Language Server Protocol, data types
 
 description:         An implementation of the types to allow language implementors to
diff --git a/src/Language/Haskell/LSP/Types/DataTypesJSON.hs b/src/Language/Haskell/LSP/Types/DataTypesJSON.hs
--- a/src/Language/Haskell/LSP/Types/DataTypesJSON.hs
+++ b/src/Language/Haskell/LSP/Types/DataTypesJSON.hs
@@ -1623,16 +1623,13 @@
 data HoverContents =
     HoverContentsMS (List MarkedString)
   | HoverContents   MarkupContent
-  | HoverContentsEmpty
   deriving (Read,Show,Eq)
 
 instance ToJSON HoverContents where
   toJSON (HoverContentsMS  x) = toJSON x
   toJSON (HoverContents    x) = toJSON x
-  toJSON (HoverContentsEmpty) = A.Null
 instance FromJSON HoverContents where
   parseJSON v@(A.String _) = HoverContentsMS <$> parseJSON v
-  parseJSON   (A.Null)     = pure HoverContentsEmpty
   parseJSON v@(A.Array _)  = HoverContentsMS <$> parseJSON v
   parseJSON v@(A.Object _) = HoverContents   <$> parseJSON v
                          <|> HoverContentsMS <$> parseJSON v
@@ -1646,10 +1643,8 @@
 #endif
 
 instance Monoid HoverContents where
-  mempty = HoverContentsEmpty
+  mempty = HoverContentsMS (List [])
 
-  HoverContentsEmpty `mappend` hc = hc
-  hc `mappend` HoverContentsEmpty = hc
   HoverContents h1   `mappend` HoverContents         h2   = HoverContents (h1 `mappend` h2)
   HoverContents h1   `mappend` HoverContentsMS (List h2s) = HoverContents (mconcat (h1: (map toMarkupContent h2s)))
   HoverContentsMS (List h1s) `mappend` HoverContents         h2    = HoverContents (mconcat ((map toMarkupContent h1s) ++ [h2]))
diff --git a/src/Language/Haskell/LSP/Types/Uri.hs b/src/Language/Haskell/LSP/Types/Uri.hs
--- a/src/Language/Haskell/LSP/Types/Uri.hs
+++ b/src/Language/Haskell/LSP/Types/Uri.hs
@@ -58,7 +58,7 @@
 
 platformAdjustToUriPath :: SystemOS -> FilePath -> String
 platformAdjustToUriPath systemOS srcPath =
-  if systemOS /= windowsOS then srcPath
+  if systemOS /= windowsOS || null srcPath then srcPath
     else let
       drive:rest = FPW.splitDirectories srcPath
       leaveCharUnescaped = (/= ':')