Wie den vollen Stack-Trace für Asynchron-Ausführung

Question

Für ein kleines Beispiel wie

import 'dart:async'; 
import 'package:stack_trace/stack_trace.dart'; 

void main() { 
    scheduleAsync(); 
} 

void scheduleAsync() { 
    new Future.delayed(new Duration(seconds: 1)) 
     .then((_) => runAsync()); 
} 

void runAsync() { 
    throw 'oh no!'; 
} 

zu bekommen bekomme ich diesen Stack-Trace. Am weitesten kann ich den Rückruf zurückverfolgen, ist der runAsync() Anruf in scheduleAsync(). Es ist keine Information übrig, dass scheduleAsync von main aufgerufen wurde.

 
Unhandled exception: 
Uncaught Error: oh no! 
Stack Trace: 
#0  runAsync (file:///home/myuser/dart/playground/bin/stack_trace/main.dart:14:3) 
#1  scheduleAsync. (file:///home/myuser/dart/playground/bin/stack_trace/main.dart:10:28) 
#2  _RootZone.runUnary (dart:async/zone.dart:1155) 
#3  _Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:484) 
#4  _Future._propagateToListeners (dart:async/future_impl.dart:567) 
#5  _Future._complete (dart:async/future_impl.dart:348) 
#6  Future.Future.delayed. (dart:async/future.dart:228) 
#7  Timer._createTimer. (dart:async-patch/timer_patch.dart:16) 
#8  _Timer._runTimers (dart:isolate-patch/timer_impl.dart:385) 
#9  _handleMessage (dart:isolate-patch/timer_impl.dart:411) 
#10  _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:142) 

#0  _rootHandleUncaughtError. (dart:async/zone.dart:886) 
#1  _asyncRunCallbackLoop (dart:async/schedule_microtask.dart:41) 
#2  _asyncRunCallback (dart:async/schedule_microtask.dart:48) 
#3  _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:96) 
#4  _Timer._runTimers (dart:isolate-patch/timer_impl.dart:392) 
#5  _handleMessage (dart:isolate-patch/timer_impl.dart:411) 
#6  _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:142) 

Process finished with exit code 255 

Gibt es eine Möglichkeit, die vollständige Stack-Trace zu erhalten?

Answer 1

Das stack_trace Paket https://pub.dartlang.org/packages/stack_trace setzt den gesamten Stack-Trace zusammen.

Siehe auch
- this blog post von einem Entwickler des Pakets stack_trace.
- http://news.dartlang.org/2016/01/unboxing-packages-stacktrace.html?m=1

import 'dart:async'; 
import 'package:stack_trace/stack_trace.dart'; 

void main() { 
    Chain.capture(() { 
    scheduleAsync(); // <= pass my code in Chain.capture 
    }, onError: (error, stack) { 
     print(error); 
     print(stack); 
    }); 
} 

void scheduleAsync() { 
    new Future.delayed(new Duration(seconds: 1)) 
     .then((_) => runAsync()); 
} 

void runAsync() { 
    throw 'oh no!'; 
} 

erzeugt diese Ausgabe, die auf die erste Zeile in main zurückverfolgen lässt.

 
oh no! 
main.dart 19:3            runAsync 
main.dart 15:28            scheduleAsync. 
package:stack_trace/src/stack_zone_specification.dart 134:26 registerUnaryCallback.. 
package:stack_trace/src/stack_zone_specification.dart 210:15 StackZoneSpecification._run 
package:stack_trace/src/stack_zone_specification.dart 134:18 registerUnaryCallback. 
dart:async/zone.dart 902          _rootRunUnary 
dart:async/zone.dart 804          _CustomZone.runUnary 
dart:async/future_impl.dart 484        _Future._propagateToListeners.handleValueCallback 
dart:async/future_impl.dart 567        _Future._propagateToListeners 
dart:async/future_impl.dart 348        _Future._complete 
dart:async/future.dart 228         Future.Future.delayed. 
package:stack_trace/src/stack_zone_specification.dart 210:15 StackZoneSpecification._run 
package:stack_trace/src/stack_zone_specification.dart 124:52 registerCallback. 
dart:async/zone.dart 891          _rootRun 
dart:async/zone.dart 796          _CustomZone.run 
dart:async/zone.dart 704          _CustomZone.runGuarded 
dart:async/zone.dart 729          _CustomZone.bindCallback. 
package:stack_trace/src/stack_zone_specification.dart 210:15 StackZoneSpecification._run 
package:stack_trace/src/stack_zone_specification.dart 124:52 registerCallback. 
dart:async/zone.dart 895          _rootRun 
dart:async/zone.dart 796          _CustomZone.run 
dart:async/zone.dart 704          _CustomZone.runGuarded 
dart:async/zone.dart 729          _CustomZone.bindCallback. 
dart:async-patch/timer_patch.dart 16       Timer._createTimer. 
dart:isolate-patch/timer_impl.dart 385      _Timer._runTimers 
dart:isolate-patch/timer_impl.dart 411      _handleMessage 
dart:isolate-patch/isolate_patch.dart 142      _RawReceivePortImpl._handleMessage 
===== asynchronous gap =========================== 
dart:async/zone.dart 828          _CustomZone.registerUnaryCallback 
dart:async/future_impl.dart 208        _Future.then 
main.dart 15:12            scheduleAsync 
main.dart 6:18            main. 
package:stack_trace/src/chain.dart 82:24      Chain.capture. 
dart:async/zone.dart 895          _rootRun 
dart:async/zone.dart 796          _CustomZone.run 
dart:async/zone.dart 1251          runZoned 
package:stack_trace/src/chain.dart 80:20      Chain.capture 
main.dart 5:16            main 
dart:isolate-patch/isolate_patch.dart 255      _startIsolate. 
dart:isolate-patch/isolate_patch.dart 142      _RawReceivePortImpl._handleMessage 


Process finished with exit code 0 

Noch mehr nützlich ist die lapidare Version

import 'dart:async'; 
import 'package:stack_trace/stack_trace.dart'; 

void main() { 
    Chain.capture(() { 
    scheduleAsync(); 
    }, onError: (error, stack) { 
     print(error); 
     print(new Trace.from(stack).terse); 
    }); 
} 

void scheduleAsync() { 
    new Future.delayed(new Duration(seconds: 1)) 
     .then((_) => runAsync()); 
} 

void runAsync() { 
    throw 'oh no!'; 
} 

, die produziert:

 
oh no! 
main.dart 19:3  runAsync 
main.dart 15:28  scheduleAsync. 
===== asynchronous gap =========================== 
dart:async   _Future.then 
main.dart 15:12  scheduleAsync 
main.dart 6:18  main. 
package:stack_trace Chain.capture 
main.dart 5:16  main 


Process finished with exit code 0