import * as vscode from 'vscode'; import * as lc from 'vscode-languageclient'; import { Ctx, sendRequestWithRetry } from './ctx'; export function activateInlayHints(ctx: Ctx) { const hintsUpdater = new HintsUpdater(ctx); vscode.window.onDidChangeVisibleTextEditors(async _ => { await hintsUpdater.refresh(); }, ctx.subscriptions); vscode.workspace.onDidChangeTextDocument(async e => { if (e.contentChanges.length === 0) return; if (e.document.languageId !== 'rust') return; await hintsUpdater.refresh(); }, ctx.subscriptions); vscode.workspace.onDidChangeConfiguration(_ => { hintsUpdater.setEnabled(ctx.config.displayInlayHints); }, ctx.subscriptions); ctx.onDidRestart(_ => hintsUpdater.setEnabled(ctx.config.displayInlayHints)); } interface InlayHintsParams { textDocument: lc.TextDocumentIdentifier; } interface InlayHint { range: vscode.Range; kind: string; label: string; } const typeHintDecorationType = vscode.window.createTextEditorDecorationType({ after: { color: new vscode.ThemeColor('rust_analyzer.inlayHint'), }, }); class HintsUpdater { private pending: Map = new Map(); private ctx: Ctx; private enabled: boolean; constructor(ctx: Ctx) { this.ctx = ctx; this.enabled = ctx.config.displayInlayHints; } async setEnabled(enabled: boolean) { if (this.enabled == enabled) return; this.enabled = enabled; if (this.enabled) { await this.refresh(); } else { this.allEditors.forEach(it => this.setDecorations(it, [])); } } async refresh() { if (!this.enabled) return; const promises = this.allEditors.map(it => this.refreshEditor(it)); await Promise.all(promises); } private async refreshEditor(editor: vscode.TextEditor): Promise { const newHints = await this.queryHints(editor.document.uri.toString()); if (newHints == null) return; const newDecorations = newHints.map(hint => ({ range: hint.range, renderOptions: { after: { contentText: `: ${hint.label}`, }, }, })); this.setDecorations(editor, newDecorations); } private get allEditors(): vscode.TextEditor[] { return vscode.window.visibleTextEditors.filter( editor => editor.document.languageId === 'rust', ); } private setDecorations( editor: vscode.TextEditor, decorations: vscode.DecorationOptions[], ) { editor.setDecorations( typeHintDecorationType, this.enabled ? decorations : [], ); } private async queryHints(documentUri: string): Promise { let client = this.ctx.client; if (!client) return null; const request: InlayHintsParams = { textDocument: { uri: documentUri }, }; let tokenSource = new vscode.CancellationTokenSource(); let prev = this.pending.get(documentUri); if (prev) prev.cancel(); this.pending.set(documentUri, tokenSource); try { return await sendRequestWithRetry( client, 'rust-analyzer/inlayHints', request, tokenSource.token, ); } finally { if (!tokenSource.token.isCancellationRequested) { this.pending.delete(documentUri); } } } }