* I updated the setOptions function so it now also returns the generated hashBytes inside the monadic tuple (earlier, it was only returning the flags and the target).

* To thread this down, I added a new rawComponentHash field as a Maybe B.ByteString to the RawComponentInfo data type. This passes the hash from setOptions straight into getCacheDirsDefault.
* Inside getCacheDirsDefault, I added a check:
  * If we have Just mFirstHash, I set the prefix to 'main'. Then, I initiate a new hash and update it with mFirstHash using H.updates, storing this mutated context as baseCtx.
  * If it's Nothing, baseCtx just gets a standard H.init.
* Finally, for opts_hash, it takes that baseCtx and updates it with the opts string (converted via B.pack). This gives out the final 40-character hex string for the SHA1 hash.
 (Also updated getCacheDirs in the session loading to accept the ByteString).
This keeps the path short and stops Windows from crashing

Author: adpad-13

ghcide/session-loader/Development/IDE/Session.hs

@@ -40,6 +40,7 @@ import           Data.List.Extra                     as L
 import qualified Data.Map.Strict                     as Map
 import           Data.Maybe
 import           Data.Proxy
+
 import qualified Data.Text                           as T
 import           Data.Version
 import           Development.IDE.Core.RuleTypes
@@ -682,8 +683,10 @@ loadSessionWithOptions recorder SessionLoadingOptions{..} rootDir que = do
               , sessionLoadingOptions = newSessionLoadingOptions
               }
 
+
         writeTQueue que (runReaderT (getOptionsLoop recorder sessionShake sessionState knownTargetsVar) sessionEnv)
 
+
     -- Each one of deps will be registered as a FileSystemWatcher in the GhcSession action
     -- so that we can get a workspace/didChangeWatchedFiles notification when a dep changes.
     -- The GlobPattern of a FileSystemWatcher can be absolute or relative.
@@ -1072,8 +1075,10 @@ toFlagsMap :: TargetDetails -> [(NormalizedFilePath, (IdeResult HscEnvEq, Depend
 toFlagsMap TargetDetails{..} =
     [ (l, (targetEnv, targetDepends)) | l <-  targetLocations]
 
+
 -- | Mapping from @hie.yaml@ to all components that have been loaded
 -- from this @hie.yaml@ location.
+
 --
 -- See Note [Multi Cradle Dependency Info]
 type HieMap = Map.Map (Maybe FilePath) [RawComponentInfo]
@@ -1102,6 +1107,7 @@ memoIO op = do
                 return (Map.insert k res mp, res)
             Just res -> return (mp, res)
 
+
 ----------------------------------------------------------------------------------------------------
 
 data PackageSetupException