dhall-haskell/dhall-lsp-server/src/Dhall/LSP/Server.hs
Frederik Ramcke 5f3b05a8f2 dhall-lsp-server: Implement completion support (#1190)
* Implement completion support

Completes the following:
- environment variables
- local imports
- identifiers in scope (as well as built-ins)
- record projections
- union constructors

* Add support for general dependent types

Removes the non-dependent let path. Needed since #1164 added support for
general dependent types.

* Remove unused import

* Use monad instance to cast between `Expr Src _`

As suggested by @Gabriel439: Use `typeOf (do _ <- expr; holeExpr)`
instead of `fmap undefined expr`. In the absence of `Embed` constructors
(in this case `Import`s) the two are equivalent.

* Simplify completeFromContext

Caught by @Gabriel439

* Remove debug code

* Add 1s timeout to listDirectory call

As pointed out by @Gabriel439, listDirectory can be a potentially
expensive operation. Adding a timeout should improve the user
experience.

* Fix unclean merge
2019-08-07 14:11:59 +00:00

103 lines
5.1 KiB
Haskell

{-| This is the entry point for the LSP server. -}
module Dhall.LSP.Server(run) where
import Control.Concurrent.MVar
import Data.Default
import qualified Language.Haskell.LSP.Control as LSP.Control
import qualified Language.Haskell.LSP.Core as LSP.Core
import qualified Language.Haskell.LSP.Types as J
import Data.Text (Text)
import qualified System.Log.Logger
import Dhall.LSP.State
import Dhall.LSP.Handlers (nullHandler, wrapHandler, hoverHandler,
didOpenTextDocumentNotificationHandler, didSaveTextDocumentNotificationHandler,
executeCommandHandler, documentFormattingHandler, documentLinkHandler,
completionHandler)
-- | The main entry point for the LSP server.
run :: Maybe FilePath -> IO ()
run mlog = do
setupLogger mlog
state <- newEmptyMVar
-- these two are stubs since we do not use a config
let onInitialConfiguration :: J.InitializeRequest -> Either Text ()
onInitialConfiguration _ = Right ()
let onConfigurationChange :: J.DidChangeConfigurationNotification -> Either Text ()
onConfigurationChange _ = Right ()
-- Callback that is called when the LSP server is started; makes the lsp
-- state (LspFuncs) available to the message handlers through the `state` MVar.
let onStartup :: LSP.Core.LspFuncs () -> IO (Maybe J.ResponseError)
onStartup lsp = do
putMVar state (initialState lsp)
return Nothing
_ <- LSP.Control.run (LSP.Core.InitializeCallbacks {..})
(lspHandlers state)
lspOptions
Nothing
return ()
-- | sets the output logger.
-- | if no filename is provided then logger is disabled, if input is string `[OUTPUT]` then log goes to stderr,
-- | which then redirects inside VSCode to the output pane of the plugin.
setupLogger :: Maybe FilePath -> IO () -- TODO: ADD verbosity
setupLogger Nothing = pure ()
setupLogger (Just "[OUTPUT]") = LSP.Core.setupLogger Nothing [] System.Log.Logger.DEBUG
setupLogger file = LSP.Core.setupLogger file [] System.Log.Logger.DEBUG
-- Tells the LSP client to notify us about file changes. Handled behind the
-- scenes by haskell-lsp (in Language.Haskell.LSP.VFS); we don't handle the
-- corresponding notifications ourselves.
syncOptions :: J.TextDocumentSyncOptions
syncOptions = J.TextDocumentSyncOptions
{ J._openClose = Just True
, J._change = Just J.TdSyncIncremental
, J._willSave = Just False
, J._willSaveWaitUntil = Just False
, J._save = Just $ J.SaveOptions $ Just False
}
-- Server capabilities. Tells the LSP client that we can execute commands etc.
lspOptions :: LSP.Core.Options
lspOptions = def { LSP.Core.textDocumentSync = Just syncOptions
, LSP.Core.completionProvider =
Just (J.CompletionOptions {
_resolveProvider = Nothing
, _triggerCharacters = Just [":", ".", "/"] })
, LSP.Core.executeCommandProvider =
-- Note that this registers the dhall.server.lint command
-- with VSCode, which means that our plugin can't expose a
-- command of the same name. In the case of dhall.lint we
-- name the server-side command dhall.server.lint to work
-- around this peculiarity.
Just (J.ExecuteCommandOptions
(J.List ["dhall.server.lint",
"dhall.server.annotateLet",
"dhall.server.freezeImport",
"dhall.server.freezeAllImports"]))
, LSP.Core.documentLinkProvider =
Just (J.DocumentLinkOptions { _resolveProvider = Just False })
}
lspHandlers :: MVar ServerState -> LSP.Core.Handlers
lspHandlers state
= def { LSP.Core.initializedHandler = Just $ wrapHandler state nullHandler
, LSP.Core.hoverHandler = Just $ wrapHandler state hoverHandler
, LSP.Core.didOpenTextDocumentNotificationHandler = Just $ wrapHandler state didOpenTextDocumentNotificationHandler
, LSP.Core.didChangeTextDocumentNotificationHandler = Just $ wrapHandler state nullHandler
, LSP.Core.didSaveTextDocumentNotificationHandler = Just $ wrapHandler state didSaveTextDocumentNotificationHandler
, LSP.Core.didCloseTextDocumentNotificationHandler = Just $ wrapHandler state nullHandler
, LSP.Core.cancelNotificationHandler = Just $ wrapHandler state nullHandler
, LSP.Core.responseHandler = Just $ wrapHandler state nullHandler
, LSP.Core.executeCommandHandler = Just $ wrapHandler state executeCommandHandler
, LSP.Core.documentFormattingHandler = Just $ wrapHandler state documentFormattingHandler
, LSP.Core.documentLinkHandler = Just $ wrapHandler state documentLinkHandler
, LSP.Core.completionHandler = Just $ wrapHandler state completionHandler
}