| // Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| /// Helper for debug JS nodes. |
| |
| library js.debug; |
| |
| import 'package:js_ast/js_ast.dart'; |
| import '../util/util.dart' show Indentation, Tagging; |
| |
| /// Unparse the JavaScript [node]. |
| String nodeToString(Node node) { |
| JavaScriptPrintingOptions options = new JavaScriptPrintingOptions( |
| shouldCompressOutput: true, |
| preferSemicolonToNewlineInMinifiedOutput: true); |
| LenientPrintingContext printingContext = |
| new LenientPrintingContext(); |
| new Printer(options, printingContext).visit(node); |
| return printingContext.getText(); |
| } |
| |
| /// Visitor that creates an XML-like representation of the structure of a |
| /// JavaScript [Node]. |
| class DebugPrinter extends BaseVisitor with Indentation, Tagging<Node> { |
| StringBuffer sb = new StringBuffer(); |
| |
| void visitNodeWithChildren(Node node, String type) { |
| openNode(node, type); |
| node.visitChildren(this); |
| closeNode(); |
| } |
| |
| @override |
| void visitNode(Node node) { |
| visitNodeWithChildren(node, '${node.runtimeType}'); |
| } |
| |
| @override |
| void visitName(Name node) { |
| openAndCloseNode(node, '${node.runtimeType}', {'name': node.name}); |
| } |
| |
| @override |
| void visitLiteralString(LiteralString node) { |
| openAndCloseNode(node, '${node.runtimeType}', {'value': node.value}); |
| } |
| |
| /** |
| * Pretty-prints given node tree into string. |
| */ |
| static String prettyPrint(Node node) { |
| var p = new DebugPrinter(); |
| node.accept(p); |
| return p.sb.toString(); |
| } |
| } |
| |
| /// Simple printing context that doesn't throw on errors. |
| class LenientPrintingContext extends SimpleJavaScriptPrintingContext { |
| @override |
| void error(String message) { |
| buffer.write('>>$message<<'); |
| } |
| } |