test: disconnect and reconnect to LSP (#396)

client/src/engine/jobs.ts

@@ -32,6 +32,7 @@ export enum Request {
   apiRemJar = 'api/remJar',
   apiVersion = 'api/version',
   apiShutdown = 'api/shutdown',
+  apiDisconnect = 'api/disconnect',
 
   lspCheck = 'lsp/check',
   lspCodelens = 'lsp/codelens',

client/src/extension.ts

@@ -134,6 +134,7 @@ export async function activate(context: vscode.ExtensionContext, launchOptions:
   // Register commands for command palette
   registerCommand('flix.internalRestart', makeHandleRestartClient(context, { shouldUpdateFlix: false }))
   registerCommand('flix.internalDownloadLatest', makeHandleRestartClient(context, { shouldUpdateFlix: true }))
+  registerCommand('flix.simulateDisconnect', handlers.simulateDisconnect(client))
   registerCommand('flix.runMain', handlers.runMain(context, launchOptions))
 
   registerCommand('flix.cmdInit', handlers.cmdInit(context, launchOptions))

client/src/handlers/handlers.ts

@@ -11,6 +11,14 @@ const _ = require('lodash/fp')
 
 let flixTerminal: vscode.Terminal | null = null
 
+/**
+ * Request that the server should disconnect. Returns promise that will resolve when the server has been reconnected.
+ * Used for testing purposes.
+ */
+export function simulateDisconnect(client: LanguageClient) {
+  return () => client.sendNotification(jobs.Request.apiDisconnect)
+}
+
 export function makeHandleRunJob(client: LanguageClient, request: jobs.Request) {
   return function handler() {
     client.sendNotification(request)

server/src/engine/flix.ts

@@ -69,6 +69,11 @@ export function updateUserConfiguration(userConfiguration: UserConfiguration) {
   _.set(userConfiguration, 'userConfiguration', startEngineInput)
 }
 
+export function simulateDisconnect() {
+  const job = { request: jobs.Request.apiDisconnect }
+  queue.enqueue(job)
+}
+
 export async function start(input: StartEngineInput) {
   if (flixInstance || socket.isOpen()) {
     await stop()

server/src/engine/jobs.ts

@@ -32,6 +32,7 @@ export enum Request {
   apiRemJar = 'api/remJar',
   apiVersion = 'api/version',
   apiShutdown = 'api/shutdown',
+  apiDisconnect = 'api/disconnect',
 
   lspCheck = 'lsp/check',
   lspCodelens = 'lsp/codelens',

server/src/handlers/handlers.ts

@@ -91,6 +91,14 @@ export function handleReplaceConfiguration(userConfiguration: engine.UserConfigu
   engine.updateUserConfiguration(userConfiguration)
 }
 
+/**
+ * Simulates the language server disconnecting.
+ * Used for testing.
+ */
+export function handleDisconnect() {
+  engine.simulateDisconnect()
+}
+
 /**
  * Runs when both client and server are ready.
  */

server/src/server.ts

@@ -19,6 +19,8 @@ connection.onInitialize(handlers.handleInitialize)
 // The user has changed something in the configuration
 connection.onNotification(jobs.Request.internalReplaceConfiguration, handlers.handleReplaceConfiguration)
 
+connection.onNotification(jobs.Request.apiDisconnect, handlers.handleDisconnect)
+
 // Event happens once after either startup or a restart - starts the engine
 connection.onNotification(jobs.Request.internalReady, handlers.handleReady)
 

test/src/disconnect.test.ts

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2024 Holger Dal Mogensen
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import * as assert from 'assert'
+import * as vscode from 'vscode'
+import { getTestDocUri } from './util'
+
+suite('Server disconnect', () => {
+  test('When server is disconnected a reconnection should happen automatically', async () => {
+    await vscode.commands.executeCommand('flix.simulateDisconnect')
+
+    // Ensure that the server is reconnected
+    const docUri = getTestDocUri('src/Main.flix')
+    const position = new vscode.Position(9, 12)
+    const r = (await vscode.commands.executeCommand('vscode.executeHoverProvider', docUri, position)) as vscode.Hover[]
+    const contents = r[0].contents[0] as vscode.MarkdownString
+    assert.strictEqual(contents.value.includes('Type'), true)
+  })
+})