Add workspace/executeCommand and clearIndexCache command

build.sbt

@@ -58,6 +58,7 @@ lazy val V = new {
   val scala212 = "2.12.4"
   val scalameta = "2.1.5"
   val scalafix = "0.5.7"
+  val enumeratum = "1.5.12"
 }
 
 lazy val noPublish = List(
@@ -81,7 +82,7 @@ lazy val languageserver = project
     resolvers += Resolver.bintrayRepo("dhpcs", "maven"),
     libraryDependencies ++= Seq(
       "com.dhpcs" %% "scala-json-rpc" % "2.0.1",
-      "com.beachape" %% "enumeratum" % "1.5.12",
+      "com.beachape" %% "enumeratum" % V.enumeratum,
       "com.beachape" %% "enumeratum-play-json" % "1.5.12-2.6.0-M7",
       "com.typesafe.scala-logging" %% "scala-logging" % "3.7.2",
       "io.monix" %% "monix" % "2.3.0",
@@ -116,6 +117,7 @@ lazy val metaserver = project
       "io.get-coursier" %% "coursier-cache" % coursier.util.Properties.version,
       "ch.epfl.scala" % "scalafix-cli" % V.scalafix cross CrossVersion.full,
       "org.scalameta" %% "semanticdb-scalac" % V.scalameta cross CrossVersion.full,
+      "com.beachape" %% "enumeratum" % V.enumeratum,
       "com.lihaoyi" %% "utest" % "0.6.0" % Test,
       "org.scalameta" %% "testkit" % V.scalameta % Test,
     )

languageserver/src/main/scala/langserver/core/LanguageServer.scala

@@ -23,6 +23,7 @@ class LanguageServer(inStream: InputStream, outStream: OutputStream)(implicit s:
       case ("textDocument/hover", request: TextDocumentHoverRequest) => hover(request)
       case ("textDocument/references", request: TextDocumentReferencesRequest) => references(request)
       case ("textDocument/signatureHelp", request: TextDocumentSignatureHelpRequest) => signatureHelp(request)
+      case ("workspace/executeCommand", request: WorkspaceExecuteCommandRequest) => executeCommand(request).map(_ => ExecuteCommandResult)
       case ("shutdown", _: Shutdown) => shutdown()
       case c => Task.raiseError(new IllegalArgumentException(s"Unknown command $c"))
     }
@@ -68,6 +69,8 @@ class LanguageServer(inStream: InputStream, outStream: OutputStream)(implicit s:
   def references(request: TextDocumentReferencesRequest): Task[ReferencesResult] = Task.now(ReferencesResult(Nil))
   def signatureHelp(request: TextDocumentSignatureHelpRequest): Task[SignatureHelpResult] = Task.now(SignatureHelpResult(Nil, None, None))
 
+  // workspace
+  def executeCommand(request: WorkspaceExecuteCommandRequest): Task[Unit] = Task.now(())
 
   def onOpenTextDocument(td: TextDocumentItem): Unit = {
     logger.debug(s"openTextDocument $td")
@@ -88,5 +91,4 @@ class LanguageServer(inStream: InputStream, outStream: OutputStream)(implicit s:
   def onChangeWatchedFiles(changes: Seq[FileEvent]): Unit =
     logger.debug(s"changeWatchedFiles $changes")
 
-
 }

languageserver/src/main/scala/langserver/messages/Commands.scala

@@ -106,7 +106,11 @@ case class ServerCapabilities(
   /**
    * The server provides rename support.
    */
-  renameProvider: Boolean = false
+  renameProvider: Boolean = false,
+  /**
+   * The server provides execute command support.
+   */
+  executeCommandProvider: ExecuteCommandOptions = ExecuteCommandOptions(Nil)
 )
 
 object ServerCapabilities {
@@ -133,6 +137,11 @@ object DocumentOnTypeFormattingOptions {
   implicit val format: Format[DocumentOnTypeFormattingOptions] = Json.format[DocumentOnTypeFormattingOptions]
 }
 
+case class ExecuteCommandOptions(commands: Seq[String])
+object ExecuteCommandOptions {
+  implicit val format: Format[ExecuteCommandOptions] = Json.format[ExecuteCommandOptions]
+}
+
 case class CompletionList(isIncomplete: Boolean, items: Seq[CompletionItem]) extends ResultResponse
 object CompletionList {
   implicit val format = Json.format[CompletionList]
@@ -183,14 +192,14 @@ case class ReferenceParams(
 )
 
 case class DocumentSymbolParams(textDocument: TextDocumentIdentifier) extends ServerCommand
-
 case class TextDocumentSignatureHelpRequest(params: TextDocumentPositionParams) extends ServerCommand
 case class TextDocumentCompletionRequest(params: TextDocumentPositionParams) extends ServerCommand
 case class TextDocumentDefinitionRequest(params: TextDocumentPositionParams) extends ServerCommand
 case class TextDocumentReferencesRequest(params: ReferenceParams) extends ServerCommand
 case class TextDocumentDocumentHighlightRequest(params: TextDocumentPositionParams) extends ServerCommand
 case class TextDocumentHoverRequest(params: TextDocumentPositionParams) extends ServerCommand
 case class TextDocumentFormattingRequest(params: DocumentFormattingParams) extends ServerCommand
+case class WorkspaceExecuteCommandRequest(params: WorkspaceExecuteCommandParams) extends ServerCommand
 
 case class Hover(contents: Seq[MarkedString], range: Option[Range]) extends ResultResponse
 object Hover {
@@ -212,7 +221,8 @@ object ServerCommand extends CommandCompanion[ServerCommand] {
     "textDocument/documentHighlight" -> valueFormat(TextDocumentDocumentHighlightRequest)(_.params),
     "textDocument/hover" -> valueFormat(TextDocumentHoverRequest)(_.params),
     "textDocument/documentSymbol" -> Json.format[DocumentSymbolParams],
-    "textDocument/formatting" -> valueFormat(TextDocumentFormattingRequest)(_.params)
+    "textDocument/formatting" -> valueFormat(TextDocumentFormattingRequest)(_.params),
+    "workspace/executeCommand" -> valueFormat(WorkspaceExecuteCommandRequest)(_.params)
   )
 
   // NOTE: this is a workaround to read `shutdown` request which doesn't have parameters (scala-json-rpc requires parameters for all requests)
@@ -294,6 +304,7 @@ case class DocumentFormattingResult(params: Seq[TextEdit]) extends ResultRespons
 case class SignatureHelpResult(signatures: Seq[SignatureInformation],
                                activeSignature: Option[Int],
                                activeParameter: Option[Int]) extends ResultResponse
+case object ExecuteCommandResult extends ResultResponse
 object SignatureHelpResult {
   implicit val format = Json.format[SignatureHelpResult]
 }
@@ -311,6 +322,7 @@ object ResultResponse extends ResponseCompanion[Any] {
     "textDocument/hover" -> Json.format[Hover],
     "textDocument/documentSymbol" -> valueFormat(DocumentSymbolResult)(_.params),
     "textDocument/formatting" -> valueFormat(DocumentFormattingResult)(_.params),
+    "workspace/executeCommand" -> emptyFormat[ExecuteCommandResult.type],
     "shutdown" -> ShutdownResult.format
   )
 }

languageserver/src/main/scala/langserver/types/types.scala

@@ -317,6 +317,12 @@ object DocumentFormattingParams {
   implicit val format = Json.format[DocumentFormattingParams]
 }
 
+case class WorkspaceExecuteCommandParams(command: String, arguments: Option[Seq[JsValue]])
+object WorkspaceExecuteCommandParams {
+  implicit val format = Json.format[WorkspaceExecuteCommandParams]
+}
+
+
 /**
   * An event describing a file change.
   *

languageserver/src/main/scala/langserver/utils/JsonRpcUtils.scala

@@ -34,8 +34,14 @@ object JsonRpcUtils {
    *         )
    * }}}
    */
-   def valueFormat[A, B: Format](apply: B => A)(unapply: A => B): Format[A] = new Format[A] {
+  def valueFormat[A, B: Format](apply: B => A)(unapply: A => B): Format[A] = new Format[A] {
     override def reads(json: JsValue) = Reads.of[B].reads(json).map(apply(_))
     override def writes(o: A) = Writes.of[B].writes(unapply(o))
   }
+
+  def emptyFormat[A]: Format[A] = new Format[A] {
+    override def reads(json: JsValue) = ???
+    override def writes(u: A) = JsObject.empty
+  }
+
 }

metaserver/src/main/scala/scala/meta/languageserver/ScalametaLanguageServer.scala

@@ -3,7 +3,13 @@ package scala.meta.languageserver
 import java.io.InputStream
 import java.io.OutputStream
 import java.io.PrintStream
+import java.io.IOException
 import java.nio.file.Files
+import java.nio.file.Path
+import java.nio.file.Paths
+import java.nio.file.SimpleFileVisitor
+import java.nio.file.FileVisitResult
+import java.nio.file.attribute.BasicFileAttributes
 import scala.concurrent.duration.FiniteDuration
 import scala.meta.languageserver.compiler.CompilerConfig
 import scala.meta.languageserver.compiler.Cursor
@@ -36,6 +42,8 @@ import langserver.messages.TextDocumentFormattingRequest
 import langserver.messages.TextDocumentHoverRequest
 import langserver.messages.TextDocumentReferencesRequest
 import langserver.messages.TextDocumentSignatureHelpRequest
+import langserver.messages.WorkspaceExecuteCommandRequest
+import langserver.messages.ExecuteCommandOptions
 import langserver.types._
 import monix.eval.Task
 import monix.execution.Cancelable
@@ -135,6 +143,8 @@ class ScalametaLanguageServer(
     }
   }
 
+  private val clearIndexCacheCommand = "clearIndexCache"
+
   override def initialize(
       request: InitializeParams
   ): Task[InitializeResult] = Task {
@@ -158,7 +168,9 @@ class ScalametaLanguageServer(
       documentHighlightProvider = true,
       documentSymbolProvider = true,
       documentFormattingProvider = true,
-      hoverProvider = true
+      hoverProvider = true,
+      executeCommandProvider =
+        ExecuteCommandOptions(WorkspaceCommand.values.map(_.entryName))
     )
     InitializeResult(capabilities)
   }
@@ -289,6 +301,18 @@ class ScalametaLanguageServer(
     sourceChangeSubscriber.onNext(input)
   }
 
+  override def executeCommand(request: WorkspaceExecuteCommandRequest) = Task {
+    import WorkspaceCommand._
+    WorkspaceCommand
+      .withNameOption(request.params.command)
+      .map {
+        case ClearIndexCache =>
+          logger.info("Clearing the index cache")
+          ScalametaLanguageServer.clearCacheDirectory()
+      }
+      .getOrElse(logger.error(s"Unknown command ${request.params.command}"))
+  }
+
   override def onChangeTextDocument(
       td: VersionedTextDocumentIdentifier,
       changes: Seq[TextDocumentContentChangeEvent]
@@ -323,6 +347,27 @@ object ScalametaLanguageServer extends LazyLogging {
     path
   }
 
+  def clearCacheDirectory(): Unit =
+    Files.walkFileTree(
+      cacheDirectory.toNIO,
+      new SimpleFileVisitor[Path] {
+        override def visitFile(
+            file: Path,
+            attr: BasicFileAttributes
+        ): FileVisitResult = {
+          Files.delete(file)
+          FileVisitResult.CONTINUE
+        }
+        override def postVisitDirectory(
+            dir: Path,
+            exc: IOException
+        ): FileVisitResult = {
+          Files.delete(dir)
+          FileVisitResult.CONTINUE
+        }
+      }
+    )
+
   def compilerConfigStream(cwd: AbsolutePath)(
       implicit scheduler: Scheduler
   ): (Observer.Sync[AbsolutePath], Observable[CompilerConfig]) = {

metaserver/src/main/scala/scala/meta/languageserver/WorkspaceCommand.scala

@@ -0,0 +1,15 @@
+package scala.meta.languageserver
+
+import enumeratum.Enum
+import enumeratum.EnumEntry
+import enumeratum.EnumEntry.Uncapitalised
+
+sealed trait WorkspaceCommand extends EnumEntry with Uncapitalised
+
+case object WorkspaceCommand extends Enum[WorkspaceCommand] {
+
+  case object ClearIndexCache extends WorkspaceCommand
+
+  val values = findValues
+
+}

vscode-extension/package.json

@@ -18,6 +18,10 @@
             "command": "scalameta.restartServer",
             "category": "Scalameta Language Server",
             "title": "Restart server"
+        }, {
+            "command": "scalameta.clearIndexCache",
+            "category": "Scalameta Language Server",
+            "title": "Clear index cache"
         }]
     },
     "main": "./out/extension",

vscode-extension/src/extension.ts

@@ -7,7 +7,8 @@ import {
   LanguageClientOptions,
   ServerOptions,
   TransportKind,
-  RevealOutputChannelOn
+  RevealOutputChannelOn,
+  ExecuteCommandRequest
 } from 'vscode-languageclient';
 import { Requirements } from './requirements';
 import { exec } from 'child_process';
@@ -91,5 +92,12 @@ export async function activate(context: ExtensionContext) {
     }
   });
 
+  client.onReady().then(() => {
+    const clearIndexCacheCommand = commands.registerCommand("scalameta.clearIndexCache", async () => {
+      return client.sendRequest(ExecuteCommandRequest.type, { command: "clearIndexCache" });
+    });
+    context.subscriptions.push(clearIndexCacheCommand);
+  });
+
   context.subscriptions.push(client.start(), restartServerCommand);
 }