allow **kwargs in @sync_performer wrapped functions

Fixes #68

Author: radix

effect/_sync.py

@@ -65,11 +65,11 @@ def perform_foo(dispatcher, foo):
             return do_side_effect(foo)
     """
     @wraps(f)
-    def sync_wrapper(*args):
+    def sync_wrapper(*args, **kwargs):
         box = args[-1]
         pass_args = args[:-1]
         try:
-            box.succeed(f(*pass_args))
+            box.succeed(f(*pass_args, **kwargs))
         except:
             box.fail(sys.exc_info())
     return sync_wrapper

effect/test_sync.py

@@ -114,3 +114,13 @@ def original(something, dispatcher, intent):
         original.attr = 1
         wrapped = sync_performer(new_func)
         self.assertEqual(wrapped.__name__, 'sync_wrapper')
+
+    def test_kwargs(self):
+        """Additional kwargs are passed through."""
+        @sync_performer
+        def p(dispatcher, intent, extra):
+            return extra
+
+        dispatcher = lambda _: partial(p, extra='extra val')
+        result = sync_perform(dispatcher, Effect('foo'))
+        self.assertEqual(result, 'extra val')