emit will now queue events and not yield to loop; v2.0

eventemitter/__init__.py

@@ -1,16 +1,18 @@
-__version__ = "1.4"
+__version__ = "2.0"
 __author__ = "Rossen Georgiev"
 
 from collections import defaultdict, OrderedDict
 import gevent
 from gevent.event import AsyncResult
+from gevent.queue import Queue
 
 
 class EventEmitter(object):
     """
     Implements event emitter using ``gevent`` module.
     Every callback is executed via :meth:`gevent.spawn`.
     """
+    __worker = None
 
     def emit(self, event, *args):
         """
@@ -20,24 +22,29 @@ def emit(self, event, *args):
         :type event: any type
         :param args: any or no arguments
         """
+        if hasattr(self, '_EventEmitter__callbacks'):
+            self.__queue.put((event, args))
+            self.__queue.put((None, (event,) + args))
 
-        gevent.idle()
+            if self.__worker is None or self.__worker.ready():
+                self.__worker = gevent.spawn(self.__emit_worker)
 
-        if hasattr(self, '_EventEmitter__callbacks'):
-            if event in self.__callbacks:
-                for callback, once in list(self.__callbacks[event].items()):
-                    if once:
-                        self.remove_listener(event, callback)
-                    if isinstance(callback, AsyncResult):
-                        callback.set(args)
-                    else:
-                        gevent.spawn(callback, *args)
+    def __emit_worker(self):
+        for event, args in self.__queue:
+            if hasattr(self, '_EventEmitter__callbacks'):
+                if event in self.__callbacks:
+                    for callback, once in list(self.__callbacks[event].items()):
+                        if once:
+                            self.remove_listener(event, callback)
+                        if isinstance(callback, AsyncResult):
+                            callback.set(args)
+                        else:
+                            gevent.spawn(callback, *args)
 
-                    gevent.idle()
+                        gevent.idle()
 
-        # every event is also emitted as None
-        if event is not None:
-            self.emit(None, event, *args)
+            if self.__queue.empty():
+                break
 
     def on(self, event, callback=None, once=False):
         """
@@ -61,6 +68,7 @@ def handle_event():
 
         if not hasattr(self, '_EventEmitter__callbacks'):
             self.__callbacks = defaultdict(OrderedDict)
+            self.__queue = Queue()
 
         # when used function
         if callback:

tests/test_eventemitter.py

@@ -12,6 +12,10 @@ class Dummy(EventEmitter):
         self.dummy = Dummy()
         self.calls = 0
 
+    def idle(self):
+        for _ in range(100):
+            gevent.idle()
+
     def test_emit_with_args(self):
         @self.dummy.on('one')
         def func_one(a):
@@ -24,20 +28,28 @@ def func_two(a, b):
         self.dummy.emit('one', 1)
         self.dummy.emit('two', 10, 100)
 
+        self.idle()
         self.assertEqual(self.calls, 111)
 
+        self.dummy.emit('one', 1)
+        self.dummy.emit('two', 10, 100)
+
+        self.idle()
+        self.assertEqual(self.calls, 222)
+
     def test_emit_async(self):
         result = gevent.event.AsyncResult()
         self.dummy.on('event', result)
         self.dummy.emit('event', 1)
 
-        self.assertEqual(result.get(block=False), (1,))
+        self.assertEqual(result.get(block=True, timeout=1), (1,))
 
         result2 = gevent.event.AsyncResult()
         self.dummy.on('event', result2)
         self.dummy.emit('event', 1, 2, 3)
 
-        self.assertEqual(result2.get(block=False), (1, 2, 3))
+        self.idle()
+        self.assertEqual(result2.get(block=True, timeout=1), (1, 2, 3))
 
     def test_on(self):
         def func_one():
@@ -50,6 +62,7 @@ def func_two():
         self.dummy.on('event', func_two)
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(self.calls, 11)
 
     def test_on_decorator(self):
@@ -63,6 +76,7 @@ def func_two():
 
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(self.calls, 11)
 
     def test_once(self):
@@ -73,6 +87,7 @@ def func_one():
         self.dummy.emit('event')
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(self.calls, 1)
 
     def test_once_decorator(self):
@@ -83,16 +98,19 @@ def func_one():
         self.dummy.emit('event')
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(self.calls, 1)
 
     def test_wait_event(self):
         def tiny_worker():
             self.dummy.wait_event('event')
 
         g = gevent.spawn(tiny_worker)
+        self.idle()
 
         self.dummy.emit('event')
 
+        self.idle()
         g.get(block=False)
 
     def test_wait_event_with_timeout(self):
@@ -123,6 +141,7 @@ def func_one():
         self.dummy.emit('event')
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(self.calls, 0)
 
     def test_remove_all_listeners(self):
@@ -142,6 +161,7 @@ def func_three():
         self.dummy.emit('event')
         self.dummy.emit('other')
 
+        self.idle()
         self.assertEqual(self.calls, 0)
 
     def test_remove_all_listeners_for_event(self):
@@ -161,6 +181,7 @@ def func_three():
         self.dummy.emit('event')
         self.dummy.emit('other')
 
+        self.idle()
         self.assertEqual(self.calls, 100)
 
     def test_callback_call_order(self):
@@ -179,4 +200,5 @@ def aaa():
 
         self.dummy.emit('event')
 
+        self.idle()
         self.assertEqual(result, [3, 2, 1])