| library catch_errors; |
| |
| import 'dart:async'; |
| |
| Stream catchErrors(dynamic body()) { |
| StreamController controller; |
| |
| bool onError(e, st) { |
| controller.add(e); |
| return true; |
| } |
| |
| void onListen() { |
| runZoned(body, onError: onError); |
| } |
| |
| controller = new StreamController(onListen: onListen); |
| return controller.stream; |
| } |
| |
| runZonedScheduleMicrotask(body(), |
| {void onScheduleMicrotask(void callback()), Function onError}) { |
| if (onScheduleMicrotask == null) { |
| return runZoned(body, onError: onError); |
| } |
| HandleUncaughtErrorHandler errorHandler; |
| if (onError != null) { |
| errorHandler = (Zone self, ZoneDelegate parent, Zone zone, error, |
| StackTrace stackTrace) { |
| try { |
| return self.parent.runUnary(onError, error); |
| } catch (e, s) { |
| if (identical(e, error)) { |
| return parent.handleUncaughtError(zone, error, stackTrace); |
| } else { |
| return parent.handleUncaughtError(zone, e, s); |
| } |
| } |
| }; |
| } |
| ScheduleMicrotaskHandler asyncHandler; |
| if (onScheduleMicrotask != null) { |
| asyncHandler = (Zone self, ZoneDelegate parent, Zone zone, f()) { |
| self.parent.runUnary(onScheduleMicrotask, () => zone.runGuarded(f)); |
| }; |
| } |
| ZoneSpecification specification = new ZoneSpecification( |
| handleUncaughtError: errorHandler, scheduleMicrotask: asyncHandler); |
| Zone zone = Zone.current.fork(specification: specification); |
| if (onError != null) { |
| return zone.runGuarded(body); |
| } else { |
| return zone.run(body); |
| } |
| } |