For a small example like
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!';
}
I get this stack trace. The furthest I can trace the call back is the runAsync() call in scheduleAsync().
There is no information left, that scheduleAsync was called from main.
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
Is there a way to get the full stack trace?
The stack_trace package https://pub.dartlang.org/packages/stack_trace puts together the whole stack trace.
See also
- this blog post from a developer of the stack_trace package.
- 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!';
}
produces this output which allows trace back to the first line in main.
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
Even more useful is the terse 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!';
}
which produces:
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