hashable instance for location, range, position (#415)

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: OliverMadine

lsp-types/src/Language/LSP/Types/Common.hs

@@ -18,6 +18,7 @@ module Language.LSP.Types.Common (
 import Control.Applicative
 import Control.DeepSeq
 import Data.Aeson
+import Data.Hashable
 import Data.Int (Int32)
 import Data.Mod.Word
 import Text.Read (Read(readPrec))
@@ -33,6 +34,8 @@ newtype UInt = UInt (Mod (2^31))
   deriving stock (Generic)
   deriving anyclass (NFData)
 
+instance Hashable UInt where hashWithSalt s (UInt n) = hashWithSalt s (unMod n)
+
 instance Show UInt where
   show (UInt u) = show $ unMod u
 

lsp-types/src/Language/LSP/Types/Location.hs

@@ -4,6 +4,7 @@ module Language.LSP.Types.Location where
 
 import           Control.DeepSeq
 import           Data.Aeson.TH
+import           Data.Hashable
 import           GHC.Generics hiding (UInt)
 import           Language.LSP.Types.Common
 import           Language.LSP.Types.Uri
@@ -26,6 +27,8 @@ data Position =
 instance NFData Position
 deriveJSON lspOptions ''Position
 
+instance Hashable Position
+
 -- ---------------------------------------------------------------------
 
 data Range =
@@ -37,6 +40,8 @@ data Range =
 instance NFData Range
 deriveJSON lspOptions ''Range
 
+instance Hashable Range
+
 -- ---------------------------------------------------------------------
 
 data Location =
@@ -48,6 +53,8 @@ data Location =
 instance NFData Location
 deriveJSON lspOptions ''Location
 
+instance Hashable Location
+
 -- ---------------------------------------------------------------------
 
 -- | Represents a link between a source and a target location.