Properly map function names with named arguments.

lib/source_map_stack_trace.dart

 // 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.
 
 import 'package:path/path.dart' as p;
 import 'package:source_maps/source_maps.dart';
 import 'package:stack_trace/stack_trace.dart';
 
 /// Convert [stackTrace], a stack trace generated by dart2js-compiled
 /// JavaScript, to a native-looking stack trace using [sourceMap].
@@ skipping 63 matching lines @@
         // its member names. Use the span's identifier if available, otherwise
         // use the minified member name.
         minified
             ? (span.isIdentifier ? span.text : frame.member)
             : _prettifyMember(frame.member));
   }).where((frame) => frame != null));
 }
 
 /// Reformats a JS member name to make it look more Dart-like.
 String _prettifyMember(String member) {
   return member

[kevmoo, 2016/06/15 19:26:10]

Orthogonal: How often is this method called? During anything perf-critical?

Creating all of the RegExp instances on every call could cause a lot of unneeded
GC churn. Just curious...

[nweiz, 2016/06/15 20:29:09]

For now I don't think it's being used anywhere performance-critical. If it
starts showing up in the profiler, we can optimize it then.

       // Get rid of the noise that Firefox sometimes adds.
       .replaceAll(new RegExp(r"/?<$"), "")
-      // Get rid of arity indicators.
-      .replaceAll(new RegExp(r"\$\d+$"), "")
+      // Get rid of arity indicators and named arguments.
+      .replaceAll(new RegExp(r"\$\d+(\$[a-zA-Z_0-9]+)*$"), "")
       // Convert closures to <fn>.
       .replaceAllMapped(new RegExp(r"(_+)closure\d*\.call$"),
           // The number of underscores before "closure" indicates how nested it
           // is.
           (match) => ".<fn>" * match[1].length)
       // Get rid of explicitly-generated calls.
       .replaceAll(new RegExp(r"\.call$"), "")
       // Get rid of the top-level method prefix.
       .replaceAll(new RegExp(r"^dart\."), "")
       // Get rid of library namespaces.
       .replaceAll(new RegExp(r"[a-zA-Z_0-9]+\$"), "")
       // Get rid of the static method prefix. The class name also exists in the
       // invocation, so we're not getting rid of any information.
       .replaceAll(new RegExp(r"^[a-zA-Z_0-9]+.(static|dart)."), "")
       // Convert underscores after identifiers to dots. This runs the risk of
       // incorrectly converting members that contain underscores, but those are
       // contrary to the style guide anyway.
       .replaceAllMapped(new RegExp(r"([a-zA-Z0-9]+)_"),
           (match) => match[1] + ".");
 }