Don't trigger unneeded ActionSpyEvent for AsyncAction (mobxjs#784)

* Fix for mobxjs#734

* Update async_action.dart

* spy_test.dart: ensure that spy-event is raised only once for async actions that involve scheduleMicrotask

* Updated changelog

* Updated mobx version

* Removed unneeded newline

* Removed unneeded newline

Co-authored-by: Pavan Podila <[email protected]>

mobx/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.0.7+3
+
+- Fixed unnecessary ActionSpyEvents being triggered for AsyncAction
+
 ## 2.0.7+1 - 2.0.7+2
 
 - Package upgrades

mobx/lib/mobx.dart

@@ -65,4 +65,4 @@ export 'package:mobx/src/core.dart'
 export 'package:mobx/src/core/atom_extensions.dart';
 
 /// The current version as per `pubspec.yaml`
-const version = '2.0.7+2';
+const version = '2.0.7+3';

mobx/lib/src/api/async/async_action.dart

@@ -24,6 +24,7 @@ class AsyncAction {
   }
 
   Future<R> run<R>(Future<R> Function() body) async {
+    final actionInfo = _actions.startAction(name: _actions.name);
     try {
       return await _zone.run(body);
     } finally {
@@ -32,33 +33,23 @@ class AsyncAction {
       // Needed to make sure that all mobx state changes are
       // applied after `await run()` completes, not sure why.
       await Future.microtask(_noOp);
+      _actions.endAction(actionInfo);
     }
   }
 
   static dynamic _noOp() => null;
 
   R _run<R>(Zone self, ZoneDelegate parent, Zone zone, R Function() f) {
-    final actionInfo = _actions.startAction(name: '${_actions.name}(Zone.run)');
-    try {
-      final result = parent.run(zone, f);
-      return result;
-    } finally {
-      _actions.endAction(actionInfo);
-    }
+    final result = parent.run(zone, f);
+    return result;
   }
 
   // Will be invoked for a catch clause that has a single argument: exception or
   // when a result is produced
   R _runUnary<R, A>(
       Zone self, ZoneDelegate parent, Zone zone, R Function(A a) f, A a) {
-    final actionInfo =
-        _actions.startAction(name: '${_actions.name}(Zone.runUnary)');
-    try {
-      final result = parent.runUnary(zone, f, a);
-      return result;
-    } finally {
-      _actions.endAction(actionInfo);
-    }
+    final result = parent.runUnary(zone, f, a);
+    return result;
   }
 
   // Will be invoked for a catch clause that has two arguments: exception and stacktrace

mobx/pubspec.yaml

@@ -1,5 +1,5 @@
 name: mobx
-version: 2.0.7+2
+version: 2.0.7+3
 description: "MobX is a library for reactively managing the state of your applications. Use the power of observables, actions, and reactions to supercharge your Dart and Flutter apps."
 
 homepage: https://github.com/mobxjs/mobx.dart

mobx/test/spy_test.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:mobx/mobx.dart';
 import 'package:test/test.dart';
 
@@ -124,6 +126,41 @@ void main() {
       d();
     });
 
+    test('spy-event is raised only once when an AsyncAction is executed',
+        () async {
+      var eventCount = 0;
+      var endEventCount = 0;
+      final d = mainContext.spy((event) {
+        if (event is ActionSpyEvent) {
+          eventCount += 1;
+        }
+
+        if (event is EndedSpyEvent && event.type == 'action') {
+          endEventCount += 1;
+        }
+      });
+
+      final actionCompleter = Completer();
+      final microtaskCompleter = Completer();
+      AsyncAction('test').run(() async {
+        scheduleMicrotask(() {
+          microtaskCompleter.complete();
+        });
+        actionCompleter.complete();
+      });
+      await actionCompleter.future;
+      await microtaskCompleter.future;
+
+      // This is needed to ensure that all spy callbacks are executed
+      // before moving on to `expect`s.
+      await Future.value();
+
+      expect(eventCount, 1);
+      expect(endEventCount, 1);
+
+      d();
+    });
+
     test('spy-event is raised when a Reaction is executed', () {
       final o = Observable(0);
       final d1 = reaction((_) => o.value, (_) {}, name: 'test');