Fixing stack traces on IE10.

pkg/stack_trace/lib/src/trace.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 trace;
 
 import 'dart:collection';
 import 'dart:math' as math;
 
 import 'frame.dart';
 import 'lazy_trace.dart';
 import 'utils.dart';
 import 'vm_trace.dart';
 
 final _terseRegExp = new RegExp(r"(-patch)?(/.*)?$");
 
 /// A RegExp to match V8's stack traces.
 ///
 /// V8's traces start with a line that's either just "Error" or else is a
 /// description of the exception that occurred. That description can be multiple
 /// lines, so we just look for any line other than the first that begins with
-/// four spaces and "at".
-final _v8Trace = new RegExp(r"\n    at ");
+/// three or four spaces and "at".
+final _v8Trace = new RegExp(r"\n    ?at ");
+
+/// A RegExp to match indidual lines of V8's stack traces.
+///
+/// This is intended to filter out the leading exception details of the trace
+/// though it is possible for the message to match this as well.
+final _v8TraceLine = new RegExp(r"    ?at ");
 
 /// A RegExp to match Firefox's stack traces.
 ///
 /// Firefox's trace frames start with the name of the function in which the
 /// error occurred, possibly including its parameters inside `()`. For example,
 /// `.VW.call$0("arg")@http://pub.dartlang.org/stuff.dart.js:560`.
 final _firefoxTrace = new RegExp(r"^([.0-9A-Za-z_$/<]|\(.*\))*@");
 
 /// A RegExp to match this package's stack traces.
 final _friendlyTrace = new RegExp(r"^[^\s]+( \d+:\d+)?\s+[^\s]+($|\n)");
@@ skipping 65 matching lines @@
   /// Parses a string representation of a Dart VM stack trace.
   Trace.parseVM(String trace)
       : this(trace.trim().split("\n").map((line) => new Frame.parseVM(line)));
 
   /// Parses a string representation of a Chrome/V8 stack trace.
   Trace.parseV8(String trace)
       : this(trace.split("\n").skip(1)
           // It's possible that an Exception's description contains a line that
           // looks like a V8 trace line, which will screw this up.
           // Unfortunately, that's impossible to detect.
-          .skipWhile((line) => !line.startsWith("    at "))
+          .skipWhile((line) => !line.startsWith(_v8TraceLine))
           .map((line) => new Frame.parseV8(line)));
 
   /// Parses a string representation of an Internet Explorer stack trace.
   ///
   /// IE10+ traces look just like V8 traces. Prior to IE10, stack traces can't
   /// be retrieved.
   Trace.parseIE(String trace)
       : this.parseV8(trace);
 
   /// Parses a string representation of a Firefox stack trace.
@@ skipping 67 matching lines @@
     // Figure out the longest path so we know how much to pad.
     var longest = frames.map((frame) => frame.location.length)
         .fold(0, math.max);
 
     // Print out the stack trace nicely formatted.
     return frames.map((frame) {
       return '${padRight(frame.location, longest)}  ${frame.member}\n';
     }).join();
   }
 }