Even better stack chains with VM async/await.

lib/src/frame.dart

 // Copyright (c) 2013, 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.
 
 library frame;
 
 
 import 'package:path/path.dart' as path;
 
 import 'trace.dart';
@@ skipping 39 matching lines @@
     r'(\d*)' // The line number. Empty in Safari if it's unknown.
     r'(?::(\d*))?' // The column number. Not present in older browsers and
                    // empty in Safari if it's unknown.
     r'$');
 
 // foo/bar.dart 10:11 in Foo._bar
 // http://dartlang.org/foo/bar.dart in Foo._bar
 final _friendlyFrame = new RegExp(
     r'^(\S+)(?: (\d+)(?::(\d+))?)?\s+([^\d]\S*)$');
 
+/// A regular expression that matches asynchronous member names generated by the
+/// VM.
+final _asyncBody = new RegExp(r'<(<anonymous closure>|[^>]+)_async_body>');
+
 final _initialDot = new RegExp(r"^\.");
 
 /// A single stack frame. Each frame points to a precise location in Dart code.
 class Frame {
   /// The URI of the file in which the code is located.
   ///
   /// This URI will usually have the scheme `dart`, `file`, `http`, or `https`.
   final Uri uri;
 
   /// The line number on which the code location is located.
@@ skipping 60 matching lines @@
     }
 
     var match = _vmFrame.firstMatch(frame);
     if (match == null) {
       throw new FormatException("Couldn't parse VM stack trace line '$frame'.");
     }
 
     // Get the pieces out of the regexp match. Function, URI and line should
     // always be found. The column is optional.
     var member = match[1]
-        .replaceAll("<<anonymous closure>_async_body>", "<async>")
+        .replaceAll(_asyncBody, "<async>")
         .replaceAll("<anonymous closure>", "<fn>");
     var uri = Uri.parse(match[2]);
 
     var lineAndColumn = match[3].split(':');
     var line = lineAndColumn.length > 1 ? int.parse(lineAndColumn[1]) : null;
     var column = lineAndColumn.length > 2 ? int.parse(lineAndColumn[2]) : null;
     return new Frame(uri, line, column, member);
   }
 
   /// Parses a string representation of a Chrome/V8 stack frame.
@@ skipping 129 matching lines @@
     // their stack frames. However, if we do get a relative path, we should
     // handle it gracefully.
     if (uriOrPath.contains('\\')) return path.windows.toUri(uriOrPath);
     return Uri.parse(uriOrPath);
   }
 
   Frame(this.uri, this.line, this.column, this.member);
 
   String toString() => '$location in $member';
 }