vscode-dotty: typesafe messages

This replaces the use of strings for identifying messages by
types (WorksheetExecRequest and WorksheetPublishOutputNotification).

Also contains some light cleanup/uniformization

Author: smarter

language-server/src/dotty/tools/languageserver/worksheet/WorksheetClient.scala

@@ -4,11 +4,13 @@ import org.eclipse.lsp4j.services.LanguageClient
 import org.eclipse.lsp4j.jsonrpc.services.JsonNotification
 
 /**
- * A `LanguageClient` that supports the `worksheet/publishOutput` notification.
- *
- * @see dotty.tools.languageserver.worksheet.WorksheetExecOutput
+ * A `LanguageClient` that supports worksheet-specific notifications.
  */
 trait WorksheetClient extends LanguageClient {
+  /**
+   *  A notification that tells the client that a line of a worksheet produced
+   *  the specified output.
+   */
   @JsonNotification("worksheet/publishOutput")
   def publishOutput(output: WorksheetExecOutput): Unit
 }

language-server/src/dotty/tools/languageserver/worksheet/WorksheetMessages.scala

@@ -2,26 +2,21 @@ package dotty.tools.languageserver.worksheet
 
 import org.eclipse.lsp4j.VersionedTextDocumentIdentifier
 
+// All case classes in this file should have zero-parameters secondary
+// constructors to allow Gson to reflectively create instances on
+// deserialization without relying on sun.misc.Unsafe.
+
 /** The parameter for the `worksheet/exec` request. */
 case class WorksheetExecParams(textDocument: VersionedTextDocumentIdentifier) {
-  // Used for deserialization
-  // see https://github.com/lampepfl/dotty/pull/5102#discussion_r222055355
   def this() = this(null)
 }
 
 /** The response to a `worksheet/exec` request. */
-case class WorksheetExecResponse(success: Boolean) {
-  // Used for deserialization
-  // see https://github.com/lampepfl/dotty/pull/5102#discussion_r222055355
+case class WorksheetExecResult(success: Boolean) {
   def this() = this(false)
 }
 
-/**
- * A notification that tells the client that a line of a worksheet
- * produced the specified output.
- */
+/** The parameters to the `worksheet/publishOutput` notification. */
 case class WorksheetExecOutput(textDocument: VersionedTextDocumentIdentifier, line: Int, content: String) {
-  // Used for deserialization
-  // see https://github.com/lampepfl/dotty/pull/5102#discussion_r222055355
   def this() = this(null, 0, null)
 }

language-server/src/dotty/tools/languageserver/worksheet/WorksheetService.scala

@@ -16,18 +16,18 @@ trait WorksheetService { thisServer: DottyLanguageServer =>
   val worksheets: ConcurrentHashMap[URI, CompletableFuture[_]] = new ConcurrentHashMap()
 
   @JsonRequest
-  def exec(params: WorksheetExecParams): CompletableFuture[WorksheetExecResponse] = thisServer.synchronized {
+  def exec(params: WorksheetExecParams): CompletableFuture[WorksheetExecResult] = thisServer.synchronized {
     val uri = new URI(params.textDocument.getUri)
     val future =
       computeAsync { cancelChecker =>
         try {
           val driver = driverFor(uri)
           val sendMessage = (line: Int, msg: String) => client.publishOutput(WorksheetExecOutput(params.textDocument, line, msg))
           evaluateWorksheet(driver, uri, sendMessage, cancelChecker)(driver.currentCtx)
-          WorksheetExecResponse(success = true)
+          WorksheetExecResult(success = true)
         } catch {
           case _: Throwable =>
-            WorksheetExecResponse(success = false)
+            WorksheetExecResult(success = false)
         } finally {
           worksheets.remove(uri)
         }

language-server/test/dotty/tools/languageserver/util/actions/WorksheetAction.scala

@@ -1,6 +1,6 @@
 package dotty.tools.languageserver.util.actions
 
-import dotty.tools.languageserver.worksheet.{WorksheetExecOutput, WorksheetExecParams, WorksheetExecResponse}
+import dotty.tools.languageserver.worksheet.{WorksheetExecOutput, WorksheetExecParams, WorksheetExecResult}
 import dotty.tools.languageserver.util.embedded.CodeMarker
 
 import java.net.URI
@@ -11,7 +11,7 @@ import org.eclipse.lsp4j.VersionedTextDocumentIdentifier
 abstract class WorksheetAction extends Action {
 
   /** Triggers the evaluation of the worksheet. */
-  def triggerEvaluation(marker: CodeMarker): Exec[CompletableFuture[WorksheetExecResponse]] = {
+  def triggerEvaluation(marker: CodeMarker): Exec[CompletableFuture[WorksheetExecResult]] = {
     server.exec(WorksheetExecParams(marker.toVersionedTextDocumentIdentifier))
   }
 

vscode-dotty/src/extension.ts

@@ -11,9 +11,10 @@ import * as vscode from 'vscode';
 import { LanguageClient, LanguageClientOptions, RevealOutputChannelOn,
          ServerOptions } from 'vscode-languageclient';
 import { enableOldServerWorkaround } from './compat'
-
+import { WorksheetPublishOutputNotification } from './protocol'
 import * as worksheet from './worksheet'
 
+
 let extensionContext: ExtensionContext
 let outputChannel: vscode.OutputChannel
 export let client: LanguageClient
@@ -206,7 +207,7 @@ function run(serverOptions: ServerOptions, isOldServer: boolean) {
     enableOldServerWorkaround(client)
 
   client.onReady().then(() => {
-    client.onNotification("worksheet/publishOutput", (params) => {
+    client.onNotification(WorksheetPublishOutputNotification.type, params => {
       worksheet.handleMessage(params)
     })
   })

vscode-dotty/src/protocol.ts

@@ -0,0 +1,47 @@
+import * as vscode from 'vscode'
+import { RequestType, NotificationType } from 'vscode-jsonrpc'
+import { VersionedTextDocumentIdentifier } from 'vscode-languageserver-protocol'
+
+import { client } from './extension'
+
+/** The parameters for the `worksheet/exec` request. */
+export interface WorksheetExecParams {
+  textDocument: VersionedTextDocumentIdentifier
+}
+
+/** The result of the `worksheet/exec` request. */
+export interface WorksheetExecResult {
+  success: boolean
+}
+
+/** The parameters for the `worksheet/publishOutput` notification. */
+export interface WorksheetPublishOutputParams {
+  textDocument: VersionedTextDocumentIdentifier
+  line: number
+  content: string
+}
+
+// TODO: Can be removed once https://github.com/Microsoft/vscode-languageserver-node/pull/421
+// is merged.
+export function asVersionedTextDocumentIdentifier(textDocument: vscode.TextDocument): VersionedTextDocumentIdentifier {
+	return {
+		uri: client.code2ProtocolConverter.asUri(textDocument.uri),
+		version: textDocument.version
+	}
+}
+
+export function asWorksheetExecParams(textDocument: vscode.TextDocument): WorksheetExecParams {
+	return {
+    textDocument: asVersionedTextDocumentIdentifier(textDocument)
+	}
+}
+
+/** The `worksheet/exec` request */
+export namespace WorksheetExecRequest {
+ export const type = new RequestType<WorksheetExecParams, WorksheetExecResult, void, void>("worksheet/exec")
+}
+
+/** The `worksheet/publishOutput` notification */
+export namespace WorksheetPublishOutputNotification {
+	export const type = new NotificationType<WorksheetPublishOutputParams, void>("worksheet/publishOutput")
+}

vscode-dotty/src/worksheet.ts

@@ -1,6 +1,9 @@
 import * as vscode from 'vscode'
+
 import { client } from './extension'
-import { VersionedTextDocumentIdentifier } from 'vscode-languageserver-protocol'
+import {
+  asWorksheetExecParams, WorksheetExecRequest, WorksheetExecParams, WorksheetPublishOutputParams
+} from './protocol'
 
 /** A worksheet managed by vscode */
 class Worksheet {
@@ -61,28 +64,6 @@ class Worksheet {
   }
 }
 
-/** The parameter for the `worksheet/exec` request. */
-class WorksheetExecParams {
-  constructor(textDocument: vscode.TextDocument) {
-    this.textDocument = VersionedTextDocumentIdentifier.create(textDocument.uri.toString(), textDocument.version)
-  }
-
-  readonly textDocument: VersionedTextDocumentIdentifier
-}
-
-/** The parameter for the `worksheet/publishOutput` notification. */
-class WorksheetOutput {
-  constructor(textDocument: VersionedTextDocumentIdentifier, line: number, content: string) {
-    this.textDocument = textDocument
-    this.line = line
-    this.content = content
-  }
-
-  readonly textDocument: VersionedTextDocumentIdentifier
-  readonly line: number
-  readonly content: string
-}
-
 /**
  * The command key for evaluating a worksheet. Exposed to users as
  * `Run worksheet`.
@@ -139,7 +120,7 @@ export function evaluateWorksheet(document: vscode.TextDocument): Thenable<{}> {
       title: "Evaluating worksheet",
       cancellable: true
     }, (_, token) => {
-      return client.sendRequest("worksheet/exec", new WorksheetExecParams(worksheet.document), token)
+      return client.sendRequest(WorksheetExecRequest.type, asWorksheetExecParams(document), token)
     })
   } else {
     return Promise.reject()
@@ -173,7 +154,7 @@ function _prepareWorksheet(worksheet: Worksheet) {
  *
  * @param message The result of evaluating part of a worksheet.
  */
-export function handleMessage(output: WorksheetOutput) {
+export function handleMessage(output: WorksheetPublishOutputParams) {
 
   const editor = vscode.window.visibleTextEditors.find(e => {
     let uri = e.document.uri.toString()