import * as vscode from 'vscode'; import * as ra from '../rust-analyzer-api'; import { Ctx, Cmd, Disposable } from '../ctx'; import { isRustDocument, RustEditor, isRustEditor, sleep } from '../util'; const AST_FILE_SCHEME = "rust-analyzer"; // Opens the virtual file that will show the syntax tree // // The contents of the file come from the `TextDocumentContentProvider` export function syntaxTree(ctx: Ctx): Cmd { const tdcp = new TextDocumentContentProvider(ctx); void new AstInspector(ctx); ctx.pushCleanup(vscode.workspace.registerTextDocumentContentProvider(AST_FILE_SCHEME, tdcp)); return async () => { const editor = vscode.window.activeTextEditor; const rangeEnabled = !!editor && !editor.selection.isEmpty; const uri = rangeEnabled ? vscode.Uri.parse(`${tdcp.uri.toString()}?range=true`) : tdcp.uri; const document = await vscode.workspace.openTextDocument(uri); tdcp.eventEmitter.fire(uri); void await vscode.window.showTextDocument(document, { viewColumn: vscode.ViewColumn.Two, preserveFocus: true }); }; } class TextDocumentContentProvider implements vscode.TextDocumentContentProvider { readonly uri = vscode.Uri.parse('rust-analyzer://syntaxtree'); readonly eventEmitter = new vscode.EventEmitter(); constructor(private readonly ctx: Ctx) { vscode.workspace.onDidChangeTextDocument(this.onDidChangeTextDocument, this, ctx.subscriptions); vscode.window.onDidChangeActiveTextEditor(this.onDidChangeActiveTextEditor, this, ctx.subscriptions); } private onDidChangeTextDocument(event: vscode.TextDocumentChangeEvent) { if (isRustDocument(event.document)) { // We need to order this after language server updates, but there's no API for that. // Hence, good old sleep(). void sleep(10).then(() => this.eventEmitter.fire(this.uri)); } } private onDidChangeActiveTextEditor(editor: vscode.TextEditor | undefined) { if (editor && isRustEditor(editor)) { this.eventEmitter.fire(this.uri); } } provideTextDocumentContent(uri: vscode.Uri, ct: vscode.CancellationToken): vscode.ProviderResult { const rustEditor = this.ctx.activeRustEditor; if (!rustEditor) return ''; // When the range based query is enabled we take the range of the selection const range = uri.query === 'range=true' && !rustEditor.selection.isEmpty ? this.ctx.client.code2ProtocolConverter.asRange(rustEditor.selection) : null; const params = { textDocument: { uri: rustEditor.document.uri.toString() }, range, }; return this.ctx.client.sendRequest(ra.syntaxTree, params, ct); } get onDidChange(): vscode.Event { return this.eventEmitter.event; } } // FIXME: consider implementing this via the Tree View API? // https://code.visualstudio.com/api/extension-guides/tree-view class AstInspector implements vscode.HoverProvider, Disposable { private static readonly astDecorationType = vscode.window.createTextEditorDecorationType({ fontStyle: "normal", border: "#ffffff 1px solid", }); private rustEditor: undefined | RustEditor; constructor(ctx: Ctx) { ctx.pushCleanup(vscode.languages.registerHoverProvider({ scheme: AST_FILE_SCHEME }, this)); vscode.workspace.onDidCloseTextDocument(this.onDidCloseTextDocument, this, ctx.subscriptions); vscode.window.onDidChangeVisibleTextEditors(this.onDidChangeVisibleTextEditors, this, ctx.subscriptions); ctx.pushCleanup(this); } dispose() { this.setRustEditor(undefined); } private onDidCloseTextDocument(doc: vscode.TextDocument) { if (this.rustEditor && doc.uri.toString() === this.rustEditor.document.uri.toString()) { this.setRustEditor(undefined); } } private onDidChangeVisibleTextEditors(editors: vscode.TextEditor[]) { if (editors.every(suspect => suspect.document.uri.scheme !== AST_FILE_SCHEME)) { this.setRustEditor(undefined); return; } this.setRustEditor(editors.find(isRustEditor)); } private setRustEditor(newRustEditor: undefined | RustEditor) { if (newRustEditor !== this.rustEditor) { this.rustEditor?.setDecorations(AstInspector.astDecorationType, []); } this.rustEditor = newRustEditor; } provideHover(doc: vscode.TextDocument, hoverPosition: vscode.Position): vscode.ProviderResult { if (!this.rustEditor) return; const astTextLine = doc.lineAt(hoverPosition.line); const rustTextRange = this.parseRustTextRange(this.rustEditor.document, astTextLine.text); if (!rustTextRange) return; this.rustEditor.setDecorations(AstInspector.astDecorationType, [rustTextRange]); this.rustEditor.revealRange(rustTextRange); const rustSourceCode = this.rustEditor.document.getText(rustTextRange); const astTextRange = this.findAstRange(astTextLine); return new vscode.Hover(["```rust\n" + rustSourceCode + "\n```"], astTextRange); } private findAstRange(astLine: vscode.TextLine) { const lineOffset = astLine.range.start; const begin = lineOffset.translate(undefined, astLine.firstNonWhitespaceCharacterIndex); const end = lineOffset.translate(undefined, astLine.text.trimEnd().length); return new vscode.Range(begin, end); } private parseRustTextRange(doc: vscode.TextDocument, astLine: string): undefined | vscode.Range { const parsedRange = /\[(\d+); (\d+)\)/.exec(astLine); if (!parsedRange) return; const [begin, end] = parsedRange.slice(1).map(off => doc.positionAt(+off)); return new vscode.Range(begin, end); } }