Update CI

.github/workflows/haskell.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ghc-version: ['9.10', '9.8', '9.6', '9.4', '9.2']
+        ghc-version: ['9.12', '9.10', '9.8', '9.6', '9.4']
         # Unlikely that we'll succeed on windows and fail on macos,
         # including it is just burning CI time. But windows could have
         # path or IO issues, so worth including

cabal.project

@@ -1,4 +1,4 @@
-index-state: 2024-12-23T14:00:00Z
+index-state: 2025-06-07T00:00:00Z
 
 packages:
          ./lsp
@@ -13,7 +13,5 @@ benchmarks: True
 package lsp
   flags: +demo
 
-package lsp-types
-  -- This makes a big difference here as lsp-types
-  -- has very many independent modules
-  ghc-options: -j4
+-- Useful if available
+semaphore: true

lsp/src/Language/LSP/Server/Core.hs

@@ -322,7 +322,8 @@ defaultOptions = def
  it is parameterized over a config type variable representing the type for the
  specific configuration data the language server needs to use.
 -}
-data ServerDefinition config = forall m a.
+data ServerDefinition config
+  = forall m a.
   ServerDefinition
   { defaultConfig :: config
   -- ^ The default value we initialize the config variable to.