Index: pkg/stack_trace/lib/src/lazy_trace.dart |
diff --git a/pkg/stack_trace/lib/src/lazy_trace.dart b/pkg/stack_trace/lib/src/lazy_trace.dart |
new file mode 100644 |
index 0000000000000000000000000000000000000000..8c4482971bd6a3b4690df51e8a6b4e7975ca2d3d |
--- /dev/null |
+++ b/pkg/stack_trace/lib/src/lazy_trace.dart |
@@ -0,0 +1,34 @@ |
+// 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 lazy_trace; |
+ |
+import 'frame.dart'; |
+import 'trace.dart'; |
+ |
+/// A thunk for lazily constructing a [Trace]. |
+typedef Trace TraceThunk(); |
+ |
+/// A wrapper around a [TraceThunk]. This works around issue 9579 by avoiding |
+/// the conversion of native [StackTrace]s to strings until it's absolutely |
+/// necessary. |
+class LazyTrace implements Trace { |
+ final TraceThunk _thunk; |
+ Trace _inner; |
+ |
+ LazyTrace(this._thunk); |
+ |
+ Trace get _trace { |
+ if (_inner == null) _inner = _thunk(); |
+ return _inner; |
+ } |
+ |
+ List<Frame> get frames => _trace.frames; |
+ String get stackTrace => _trace.stackTrace; |
+ String get fullStackTrace => _trace.fullStackTrace; |
+ Trace get terse => new LazyTrace(() => _trace.terse); |
+ Trace foldFrames(bool predicate(frame)) => |
+ new LazyTrace(() => _trace.foldFrames(predicate)); |
+ String toString() => _trace.toString(); |
+} |