Display warnings if server is outdated

vscode-client/package.json

@@ -35,6 +35,8 @@
     "postinstall": "node ./node_modules/vscode/bin/install"
   },
   "dependencies": {
+    "@types/semver-compare": "^1.0.0",
+    "semver-compare": "^1.0.0",
     "vscode": "^1.1.14",
     "vscode-languageclient": "^4.1.3"
   }

vscode-client/src/extension.ts

@@ -1,18 +1,27 @@
 'use strict'
 
+import semverCompare = require('semver-compare')
 import { ExtensionContext, window, workspace } from 'vscode'
 import {
   LanguageClient,
   LanguageClientOptions,
   ServerOptions,
 } from 'vscode-languageclient'
 
-import { getServerCommand } from './util'
+import { getServerInfo } from './util'
 
-export function activate(context: ExtensionContext) {
-  getServerCommand()
-    .then(command => start(context, command))
-    .catch(_ => handleMissingExecutable())
+const MINIMUM_SERVER_VERSION = '1.1.2'
+
+export async function activate(context: ExtensionContext) {
+  try {
+    const { command, version } = await getServerInfo()
+    if (semverCompare(version, MINIMUM_SERVER_VERSION) === -1) {
+      return handleOutdatedExecutable()
+    }
+    start(context, command)
+  } catch (error) {
+    handleMissingExecutable()
+  }
 }
 
 function start(context: ExtensionContext, command: string) {
@@ -53,11 +62,12 @@ function start(context: ExtensionContext, command: string) {
   context.subscriptions.push(disposable)
 }
 
-function handleMissingExecutable() {
-  const message = `Can't find bash-language-server on your PATH. Please install it using npm i -g bash-language-server.`
-  const options = {
-    modal: false,
-  }
+function handleOutdatedExecutable() {
+  const message = `Outdated bash server. Please upgrade by running "npm i -g bash-language-server".`
+  window.showErrorMessage(message, { modal: false })
+}
 
-  window.showErrorMessage(message, options)
+function handleMissingExecutable() {
+  const message = `Can't find bash-language-server on your PATH. Please install it using "npm i -g bash-language-server".`
+  window.showErrorMessage(message, { modal: false })
 }

vscode-client/src/util.ts

@@ -17,18 +17,21 @@ function getBasePath(): Promise<string> {
   })
 }
 
-export async function getServerCommand(): Promise<string> {
+type ServerInfo = { command: string; version: string }
+
+export async function getServerInfo(): Promise<ServerInfo> {
   const basePath = await getBasePath()
   const name = isWindows() ? 'bash-language-server.cmd' : 'bash-language-server'
   const command = Path.join(basePath, name)
 
-  return new Promise<string>((resolve, reject) => {
-    // Simply check if the bash-language-server is installed.
-    execFile(command, ['-v'], err => {
+  return new Promise<ServerInfo>((resolve, reject) => {
+    execFile(command, ['-v'], (err, stdout) => {
       if (err) {
         reject(err)
       }
-      resolve(command)
+      const versionMatch = stdout.match(/\d+[.]\d+[.]\d+/)
+      const version = (versionMatch && versionMatch[0]) || '0.0.0'
+      resolve({ command, version })
     })
   })
 }

vscode-client/yarn.lock

@@ -2,6 +2,10 @@
 # yarn lockfile v1
 
 
+"@types/semver-compare@^1.0.0":
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/@types/semver-compare/-/semver-compare-1.0.0.tgz#b6e39ec7d0d3f03e5e74ec654bfbbfbc3bbe1b19"
+
 ajv@^5.1.0:
   version "5.5.2"
   resolved "https://registry.yarnpkg.com/ajv/-/ajv-5.5.2.tgz#73b5eeca3fab653e3d3f9422b341ad42205dc965"
@@ -1377,6 +1381,10 @@ safe-buffer@^5.0.1, safe-buffer@^5.1.1, safe-buffer@~5.1.0, safe-buffer@~5.1.1:
   version "5.1.1"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.1.tgz#893312af69b2123def71f57889001671eeb2c853"
 
+semver-compare@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/semver-compare/-/semver-compare-1.0.0.tgz#0dee216a1c941ab37e9efb1788f6afc5ff5537fc"
+
 semver@^5.4.1:
   version "5.5.0"
   resolved "https://registry.yarnpkg.com/semver/-/semver-5.5.0.tgz#dc4bbc7a6ca9d916dee5d43516f0092b58f7b8ab"