Dart 类型'；LazyTrace'；未加载

从Dart编辑器设置新安装的Dart Polymer项目时，出现以下错误：

--- 5:47:24 PM Starting pub serve : testing ---
Loading source assets...
Loading polymer transformers...
Serving testing web on http://localhost:8080
in ShutdownIsolate: Unhandled exception:
Uncaught Error: 'package:stack_trace/src/trace.dart': malformed type: line 107 pos 16: type 'LazyTrace' is not loaded
    return new LazyTrace(() => new Trace.parse(trace.toString()));
               ^
type error.
Stack Trace:
#0      Trace.Trace.from (package:stack_trace/src/trace.dart:107:16)
#1      Chain.Chain.forTrace (package:stack_trace/src/chain.dart:121:53)
#2      CrossIsolateException.serialize (package:$pub/serialize/exception.dart:46:43)
#3      serializeException (package:$pub/serialize/exception.dart:88:43)
#4      respond.<anonymous closure> (package:$pub/serialize.dart:164:34)
#5      _RootZone.runBinary (dart:async/zone.dart:1156)
#6      _Future._propagateToListeners.handleError (dart:async/future_impl.dart:524)
#7      _Future._propagateToListeners (dart:async/future_impl.dart:582)
#8      _Future._propagateToListeners.handleWhenCompleteCallback.<anonymous closure> (dart:async/future_impl.dart:563)
#9      _RootZone.runUnary (dart:async/zone.dart:1151)
#10     _Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:496)
#11     _Future._propagateToListeners (dart:async/future_impl.dart:579)
#12     _Future._completeWithValue (dart:async/future_impl.dart:339)
#13     _Future._asyncComplete.<anonymous closure> (dart:async/future_impl.dart:401)
#14     _asyncRunCallbackLoop (dart:async/schedule_microtask.dart:41)
#15     _asyncRunCallback (dart:async/schedule_microtask.dart:48)
#16     _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:84)
#17     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:131)

#0      _rootHandleUncaughtError.<anonymous closure> (dart:async/zone.dart:883)
#1      _asyncRunCallbackLoop (dart:async/schedule_microtask.dart:41)
#2      _asyncRunCallback (dart:async/schedule_microtask.dart:48)
#3      _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:84)
#4      _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:131)

公开发行

name: testing
description: A sample Polymer application
dependencies:
    polymer: ">=0.12.0 <0.13.0"
transformers:
- polymer:
    entry_points: web/testing.html

---

现在我看不到stack_trace包中定义的LazyTrace类。是否有人对此问题有经验？

请尝试从包含

pubspec.yaml

文件的目录运行命令行上的

pub cache repair

和

pub get

。感谢您的回答。这似乎是一个可能的解决方案，但问题仍然存在。请将您的

pubspec.yaml

、

pubspec.lock

和

dart--version

的输出添加到您的问题中。如果将版本设置为

any

，您可能会得到过时的版本。当您运行

pub-upgrade

时，输出将显示新版本的可用位置。如果您想要更新的版本，您必须向依赖项添加更具体的版本约束，如

polymer:'>=0.15.1+5'

。谢谢居里。我现在把它整理好了。

name: testing
description: A sample Polymer application
dependencies:
    polymer: ">=0.12.0 <0.13.0"
transformers:
- polymer:
    entry_points: web/testing.html

➜  testing  dart --version
Dart VM version: 1.7.2 (Tue Oct 14 06:58:25 2014) on "macos_x64"