import * as lc from 'vscode-languageclient'; import * as vscode from 'vscode'; import { Config } from './config'; import { CallHierarchyFeature } from 'vscode-languageclient/lib/callHierarchy.proposed'; import { SemanticTokensFeature, DocumentSemanticsTokensSignature } from 'vscode-languageclient/lib/semanticTokens.proposed'; export async function createClient(config: Config, serverPath: string): Promise { // '.' Is the fallback if no folder is open // 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. const workspaceFolderPath = vscode.workspace.workspaceFolders?.[0]?.uri.fsPath ?? '.'; const run: lc.Executable = { command: serverPath, options: { cwd: workspaceFolderPath }, }; const serverOptions: lc.ServerOptions = { run, debug: run, }; const traceOutputChannel = vscode.window.createOutputChannel( 'Rust Analyzer Language Server Trace', ); const cargoWatchOpts = config.cargoWatchOptions; const clientOptions: lc.LanguageClientOptions = { documentSelector: [{ scheme: 'file', language: 'rust' }], initializationOptions: { publishDecorations: !config.highlightingSemanticTokens, lruCapacity: config.lruCapacity, maxInlayHintLength: config.maxInlayHintLength, cargoWatchEnable: cargoWatchOpts.enable, cargoWatchArgs: cargoWatchOpts.arguments, cargoWatchCommand: cargoWatchOpts.command, cargoWatchAllTargets: cargoWatchOpts.allTargets, excludeGlobs: config.excludeGlobs, useClientWatching: config.useClientWatching, featureFlags: config.featureFlags, withSysroot: config.withSysroot, cargoFeatures: config.cargoFeatures, rustfmtArgs: config.rustfmtArgs, }, traceOutputChannel, middleware: { // Workaround for https://github.com/microsoft/vscode-languageserver-node/issues/576 async provideDocumentSemanticTokens(document: vscode.TextDocument, token: vscode.CancellationToken, next: DocumentSemanticsTokensSignature) { const res = await next(document, token); if (res === undefined) throw new Error('busy'); return res; } } as any }; const res = new lc.LanguageClient( 'rust-analyzer', 'Rust Analyzer Language Server', serverOptions, clientOptions, ); // HACK: This is an awful way of filtering out the decorations notifications // However, pending proper support, this is the most effecitve approach // Proper support for this would entail a change to vscode-languageclient to allow not notifying on certain messages // Or the ability to disable the serverside component of highlighting (but this means that to do tracing we need to disable hihlighting) // This also requires considering our settings strategy, which is work which needs doing // @ts-ignore The tracer is private to vscode-languageclient, but we need access to it to not log publishDecorations requests res._tracer = { log: (messageOrDataObject: string | unknown, data?: string) => { if (typeof messageOrDataObject === 'string') { if ( messageOrDataObject.includes( 'rust-analyzer/publishDecorations', ) || messageOrDataObject.includes( 'rust-analyzer/decorationsRequest', ) ) { // Don't log publish decorations requests } else { // @ts-ignore This is just a utility function res.logTrace(messageOrDataObject, data); } } else { // @ts-ignore res.logObjectTrace(messageOrDataObject); } }, }; // To turn on all proposed features use: res.registerProposedFeatures(); // Here we want to just enable CallHierarchyFeature since it is available on stable. // Note that while the CallHierarchyFeature is stable the LSP protocol is not. res.registerFeature(new CallHierarchyFeature(res)); if (config.highlightingSemanticTokens) { res.registerFeature(new SemanticTokensFeature(res)); } return res; }