Microtasks are no longer dispatched after a runtime syntax error

[nex3]

If a syntax error is encountered at runtime, it's not detected synchronously while main() is on the stack, and the isolate recovers using Isolate.setErrorsFatal(false), microtasks in that isolate will cease to be dispatched. For example:

import 'dart:async';
import 'dart:isolate';

void badFn() {continue;}

void main() {
  var errorPort = new ReceivePort();
  Isolate.current.setErrorsFatal(false);
  Isolate.current.addErrorListener(errorPort.sendPort);
  errorPort.listen((message) {
    print("caught error");
    Timer.run(() => print("after timer"));
    scheduleMicrotask(() => print("after microtask"));
  });

  scheduleMicrotask(() => badFn());
}

This prints "caught error" and "after timer", but not "after microtask".

[nex3]

See also #23684, which proposes to make runtime syntax errors thrown like other exceptions.

[natebosch]

Given that the Dart 2 VM no longer attempts to execute code with a parse error I don't think this issue is relevant anymore.