Make unwinding follow the awaiter link attached to the timeout handler,
which allows it to continue past the asynchronous gap into the
corresponding listeners. This significantly improves the stack trace:
for example a timing out `await Socket.connect()` now produces:
SocketException: Connection timed out, ...
_NativeSocket.connect.<anonymous closure>.<anonymous closure>
_RootZone.run (dart:async/zone.dart:1655:54)
Future.timeout.<anonymous closure>
<asynchronous suspension>
_RawSocket.connect.<anonymous closure>
<asynchronous suspension>
Socket._connect.<anonymous closure>
<asynchronous suspension>
main
<asynchronous suspension>
Where without this change it produced:
SocketException: Connection timed out, ...
_NativeSocket.connect.<anonymous closure>.<anonymous closure>
_RootZone.run
Future.timeout.<anonymous closure>
Timer._createTimer.<anonymous closure>
_Timer._runTimers
_Timer._handleMessage
_RawReceivePort._handleMessage
Which is much less informative.
TEST=vm/dart/awaiter_stacks
Fixes https://github.com/dart-lang/sdk/issues/56431
Change-Id: If4798e9e216ed88480a2b2b91ad6fa13dcb14ca4
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/380982
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Lasse Nielsen <lrn@google.com>
Vyacheslav Egorov
090c07ad1f