Migrate async tests to strong

tests/lib_strong/async/catch_errors13_test.dart

+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:async_helper/async_helper.dart';
+import "package:expect/expect.dart";
+import 'dart:async';
+import 'catch_errors.dart';
+
+main() {
+  asyncStart();
+  Completer done = new Completer();
+
+  var events = [];
+  // Work around bug that makes scheduleMicrotask use Timers. By invoking
+  // `scheduleMicrotask` here we make sure that asynchronous non-timer events
+  // are executed before any Timer events.
+  scheduleMicrotask(() { });
+
+  // Test that errors are caught by nested `catchErrors`. Also uses
+  // `scheduleMicrotask` in the body of a Timer.
+  bool outerTimerRan = false;
+  int outerTimerCounterDelayCount = 0;
+  catchErrors(() {
+    events.add("catch error entry");
+    catchErrors(() {
+      events.add("catch error entry2");
+      Timer.run(() { throw "timer error"; });
+
+      // We want this timer to run after the timer below. When the machine is
+      // slow we saw that the timer below was scheduled more than 50ms after
+      // this line. A duration of 50ms was therefore not enough to guarantee
+      // that this timer runs before the timer below.
+      // Instead of increasing the duration to a bigger amount we decided to
+      // verify that the other timer already ran, and reschedule if not.
+      // This way we could reduce the timeout (to 10ms now), while still
+      // allowing for more time, in case the machine is slow.
+      void runDelayed() {
+        new Timer(const Duration(milliseconds: 10),
+                  () {
+                    if (outerTimerRan) {
+                      scheduleMicrotask(() { throw "scheduleMicrotask"; });
+                      throw "delayed error";
+                    } else if (outerTimerCounterDelayCount < 100) {
+                      outerTimerCounterDelayCount++;
+                      runDelayed();
+                    }
+                  });
+      }
+
+      runDelayed();
+    }).listen((x) {
+      events.add(x);
+      if (x == "scheduleMicrotask") {
+        throw "inner done throw";
+      }
+    });
+    events.add("after inner");
+    Timer.run(() {
+      outerTimerRan = true;
+      throw "timer outer";
+    });
+    throw "inner throw";
+  }).listen((x) {
+      events.add(x);
+      if (x == "inner done throw") done.complete(true);
+    },
+    onDone: () { Expect.fail("Unexpected callback"); });
+
+  done.future.whenComplete(() {
+    // Give callbacks time to run.
+    Timer.run(() {
+      Expect.listEquals([
+                         "catch error entry",
+                         "catch error entry2",
+                         "after inner",
+                         "main exit",
+                         "inner throw",
+                         "timer error",
+                         "timer outer",
+                         "delayed error",
+                         "scheduleMicrotask",
+                         "inner done throw"
+                         ],
+                         events);
+      asyncEnd();
+    });
+  });
+  events.add("main exit");
+}