Use generator in Mailbox.get_mail to limit memory leak

django_mailbox/models.py

@@ -408,17 +408,16 @@ class Mailbox(models.Model):
         new_mail = []
         connection = self.get_connection()
         if not connection:
-            return new_mail
+            return
         for message in connection.get_message(condition):
             msg = self.process_incoming_message(message)
             if not msg is None:
-                new_mail.append(msg)
+                yield msg
         self.last_polling = now()
         if django.VERSION >= (1, 5):  # Django 1.5 introduces update_fields
             self.save(update_fields=['last_polling'])
         else:
             self.save()
-        return new_mail
 
     def __str__(self):
         return self.name

django_mailbox/tests/base.py

@@ -66,7 +66,7 @@ class EmailMessageTestCase(TestCase):
                 raise EmailIntegrationTimeout()
             messages = self.mailbox.get_new_mail(condition)
             if messages:
-                return messages
+                return list(messages)
             time.sleep(5)
 
     def _get_email_as_text(self, name):

django_mailbox/tests/test_mailbox.py

@@ -32,5 +32,5 @@ class TestMailbox(TestCase):
                 'generic_message.eml',
             ))
         self.assertEqual(mailbox.last_polling, None)
-        mailbox.get_new_mail()
+        list(mailbox.get_new_mail())
         self.assertNotEqual(mailbox.last_polling, None)