DRAFT: Completions for cabal.project files, hls-cabal-project-plugin

.gitmodules

@@ -8,3 +8,7 @@
 #     Commit git commit -m "Removed submodule <name>"
 #     Delete the now untracked submodule files
 #     rm -rf path_to_submodule
+
+[submodule "vendor/cabal"]
+	path = vendor/cabal
+	url = https://github.com/rm41339/cabal.git

cabal.project

@@ -6,7 +6,16 @@ packages:
          ./ghcide
          ./hls-plugin-api
          ./hls-test-utils
+         ./vendor/cabal/Cabal
+         ./vendor/cabal/Cabal-syntax
+         ./vendor/cabal/cabal-install
+         ./vendor/cabal/cabal-install-solver
+         ./vendor/cabal/Cabal-described
+         ./vendor/cabal/Cabal-tree-diff
 
+package cabal-install
+  tests: False
+  benchmarks: False
 
 index-state: 2025-05-12T13:26:29Z
 

haskell-language-server.cabal

@@ -317,6 +317,90 @@ test-suite hls-cabal-plugin-tests
     , text
     , hls-plugin-api
 
+-----------------------------
+-- cabal project plugin
+-----------------------------
+
+flag cabalProject
+  description: Enable cabalProject plugin
+  default:     True
+  manual:      True
+
+common cabalProject
+  if flag(cabalProject)
+    build-depends: haskell-language-server:hls-cabal-project-plugin
+    cpp-options: -Dhls_cabal_project
+
+library hls-cabal-project-plugin
+  import:           defaults, pedantic, warnings
+  if !flag(cabalProject)
+    buildable: False
+  exposed-modules:
+    Ide.Plugin.CabalProject
+    Ide.Plugin.CabalProject.Parse
+    Ide.Plugin.CabalProject.Diagnostics
+    Ide.Plugin.CabalProject.Types
+    Ide.Plugin.CabalProject.Completion.Completions
+    Ide.Plugin.CabalProject.Completion.Data
+
+  build-depends:
+    , bytestring
+    , Cabal-syntax          >= 3.7
+    , containers
+    , deepseq
+    , directory
+    , filepath
+    , extra                 >=1.7.4
+    , ghcide                == 2.11.0.0
+    , hashable
+    , hls-plugin-api        == 2.11.0.0
+    , hls-graph             == 2.11.0.0
+    , lens
+    , lsp                   ^>=2.7
+    , lsp-types             ^>=2.3
+    , regex-tdfa            ^>=1.3.1
+    , text
+    , text-rope
+    , transformers
+    , unordered-containers  >=0.2.10.0
+    , containers
+    , process
+    , aeson
+    , Cabal
+    , pretty
+    , cabal-install
+    , cabal-install-solver
+    , haskell-language-server:hls-cabal-plugin
+    , base16-bytestring
+    , cryptohash-sha1
+
+  hs-source-dirs:   plugins/hls-cabal-project-plugin/src
+
+test-suite hls-cabal-project-plugin-tests
+  import:           defaults, pedantic, test-defaults, warnings
+  if !flag(cabalProject)
+    buildable: False
+  type:             exitcode-stdio-1.0
+  hs-source-dirs:   plugins/hls-cabal-project-plugin/test
+  main-is:          Main.hs
+  other-modules:
+    Completer
+    Utils
+  build-depends:
+    , bytestring
+    , Cabal-syntax          >= 3.7
+    , extra
+    , filepath
+    , ghcide
+    , haskell-language-server:hls-cabal-project-plugin
+    , hls-test-utils    == 2.11.0.0
+    , lens
+    , lsp-types
+    , text
+    , hls-plugin-api
+    , cabal-install
+    , haskell-language-server:hls-cabal-plugin
+
 -----------------------------
 -- class plugin
 -----------------------------
@@ -1830,6 +1914,7 @@ library
                   , pedantic
                   -- plugins
                   , cabal
+                  , cabalProject
                   , callHierarchy
                   , cabalfmt
                   , cabalgild

hls-plugin-api/src/Ide/Types.hs

@@ -14,7 +14,7 @@
 {-# LANGUAGE UndecidableInstances  #-}
 {-# LANGUAGE ViewPatterns          #-}
 module Ide.Types
-( PluginDescriptor(..), defaultPluginDescriptor, defaultCabalPluginDescriptor
+( PluginDescriptor(..), defaultPluginDescriptor, defaultCabalPluginDescriptor, defaultCabalProjectPluginDescriptor
 , defaultPluginPriority
 , describePlugin
 , IdeCommand(..)
@@ -1077,6 +1077,21 @@ defaultCabalPluginDescriptor plId desc =
     Nothing
     [".cabal"]
 
+defaultCabalProjectPluginDescriptor :: PluginId -> T.Text -> PluginDescriptor ideState
+defaultCabalProjectPluginDescriptor plId desc =
+  PluginDescriptor
+    plId
+    desc
+    defaultPluginPriority
+    mempty
+    mempty
+    mempty
+    defaultConfigDescriptor
+    mempty
+    mempty
+    Nothing
+    [".project"]
+
 newtype CommandId = CommandId T.Text
   deriving (Show, Read, Eq, Ord)
 instance IsString CommandId where

plugins/hls-cabal-plugin/src/Ide/Plugin/Cabal/Diagnostics.hs

@@ -5,6 +5,8 @@ module Ide.Plugin.Cabal.Diagnostics
 , warningDiagnostic
 , positionFromCabalPosition
 , fatalParseErrorDiagnostic
+, toBeginningOfNextLine
+, mkDiag
   -- * Re-exports
 , FileDiagnostic
 , Diagnostic(..)

plugins/hls-cabal-plugin/test/testdata/completer.cabal

@@ -11,4 +11,4 @@ be
 library
     lib
 
-co
+co