editors/code/src/server.ts

   1 import { lookpath } from 'lookpath';
   2 import { homedir, platform } from 'os';
   3 import * as lc from 'vscode-languageclient';
   4
   5 import { window, workspace } from 'vscode';
   6 import { Config } from './config';
   7 import { Highlighter } from './highlighting';
   8
   9 function expandPathResolving(path: string) {
  10     if (path.startsWith('~/')) {
  11         return path.replace('~', homedir());
  12     }
  13     return path;
  14 }
  15
  16 export class Server {
  17     public static highlighter = new Highlighter();
  18     public static config = new Config();
  19     public static client: lc.LanguageClient;
  20
  21     public static async start(
  22         notificationHandlers: Iterable<[string, lc.GenericNotificationHandler]>
  23     ) {
  24         // '.' Is the fallback if no folder is open
  25         // TODO?: Workspace folders support Uri's (eg: file://test.txt). It might be a good idea to test if the uri points to a file.
  26         let folder: string = '.';
  27         if (workspace.workspaceFolders !== undefined) {
  28             folder = workspace.workspaceFolders[0].uri.fsPath.toString();
  29         }
  30
  31         const command = expandPathResolving(this.config.raLspServerPath);
  32         // FIXME: remove check when the following issue is fixed:
  33         // https://github.com/otiai10/lookpath/issues/4
  34         if (platform() !== 'win32') {
  35             if (!(await lookpath(command))) {
  36                 throw new Error(
  37                     `Cannot find rust-analyzer server \`${command}\` in PATH.`
  38                 );
  39             }
  40         }
  41         const run: lc.Executable = {
  42             command,
  43             options: { cwd: folder }
  44         };
  45         const serverOptions: lc.ServerOptions = {
  46             run,
  47             debug: run
  48         };
  49         const traceOutputChannel = window.createOutputChannel(
  50             'Rust Analyzer Language Server Trace'
  51         );
  52         const clientOptions: lc.LanguageClientOptions = {
  53             documentSelector: [{ scheme: 'file', language: 'rust' }],
  54             initializationOptions: {
  55                 publishDecorations: true,
  56                 lruCapacity: Server.config.lruCapacity,
  57                 maxInlayHintLength: Server.config.maxInlayHintLength,
  58                 excludeGlobs: Server.config.excludeGlobs,
  59                 useClientWatching: Server.config.useClientWatching,
  60                 featureFlags: Server.config.featureFlags
  61             },
  62             traceOutputChannel
  63         };
  64
  65         Server.client = new lc.LanguageClient(
  66             'rust-analyzer',
  67             'Rust Analyzer Language Server',
  68             serverOptions,
  69             clientOptions
  70         );
  71         // HACK: This is an awful way of filtering out the decorations notifications
  72         // However, pending proper support, this is the most effecitve approach
  73         // Proper support for this would entail a change to vscode-languageclient to allow not notifying on certain messages
  74         // Or the ability to disable the serverside component of highlighting (but this means that to do tracing we need to disable hihlighting)
  75         // This also requires considering our settings strategy, which is work which needs doing
  76         // @ts-ignore The tracer is private to vscode-languageclient, but we need access to it to not log publishDecorations requests
  77         Server.client._tracer = {
  78             log: (messageOrDataObject: string | any, data?: string) => {
  79                 if (typeof messageOrDataObject === 'string') {
  80                     if (
  81                         messageOrDataObject.includes(
  82                             'rust-analyzer/publishDecorations'
  83                         ) ||
  84                         messageOrDataObject.includes(
  85                             'rust-analyzer/decorationsRequest'
  86                         )
  87                     ) {
  88                         // Don't log publish decorations requests
  89                     } else {
  90                         // @ts-ignore This is just a utility function
  91                         Server.client.logTrace(messageOrDataObject, data);
  92                     }
  93                 } else {
  94                     // @ts-ignore
  95                     Server.client.logObjectTrace(messageOrDataObject);
  96                 }
  97             }
  98         };
  99         Server.client.registerProposedFeatures();
 100         Server.client.onReady().then(() => {
 101             for (const [type, handler] of notificationHandlers) {
 102                 Server.client.onNotification(type, handler);
 103             }
 104         });
 105         Server.client.start();
 106     }
 107 }