fix remove non existing events

Author: uralbash

docs/example.rst

@@ -36,9 +36,9 @@ Events registered automatically, but you can do it manually:
    from sqlalchemy.orm import mapper
 
    from sqlalchemy_mptt.events import TreesManager
-   from sqlalchemy_mptt.mixins import BaseNestedSets
+   from .models import MyUser
 
-   tree_manager = TreesManager(BaseNestedSets)
+   tree_manager = TreesManager(MyUser)
    tree_manager.register_mapper(mapper)  # register events before_insert,
                                          # before_update and before_delete
 
@@ -55,6 +55,19 @@ Or remove events if it required:
    tree_manager.register_mapper(mapper,       # remove events before_insert,
                                 remove=True)  # before_update and before_delete
 
+Or remove for your custom model:
+
+.. code-block:: python
+
+   from sqlalchemy.orm import mapper
+
+   from sqlalchemy_mptt.events import TreesManager
+   from .models import MyUser
+
+   tree_manager = TreesManager(MyUser)
+   tree_manager.register_mapper(mapper,       # remove events before_insert,
+                                remove=True)  # before_update and before_delete
+
 Data structure
 ~~~~~~~~~~~~~~
 

setup.py

@@ -10,7 +10,7 @@ def read(name):
 
 setup(
     name='sqlalchemy_mptt',
-    version='0.1.9',
+    version='0.1.9.post0',
     url='http://github.com/ITCase/sqlalchemy_mptt/',
     author='Svintsov Dmitry',
     author_email='sacrud@uralbash.ru',

sqlalchemy_mptt/events.py

@@ -361,7 +361,8 @@ def register_mapper(self, mapper, remove=False):
             ('before_delete', self.before_delete),
         ):
             if remove:
-                event.remove(self.base_class, e, h)
+                if event.contains(self.base_class, e, h):
+                    event.remove(self.base_class, e, h)
             else:
                 event.listen(self.base_class, e, h, propagate=True)
         return self

sqlalchemy_mptt/tests/__init__.py

@@ -86,6 +86,16 @@ def stop_query_counter(self):
                      self.catch_queries)
 
     def setUp(self):
+
+        # register events
+        from .test_mixins import Tree2
+        from sqlalchemy.orm import mapper
+        from sqlalchemy_mptt.events import TreesManager
+
+        tree_manager = TreesManager(Tree2)
+        tree_manager.register_mapper(mapper)
+
+        # sqla settings
         self.engine = create_engine('sqlite:///:memory:')
         Session = mptt_sessionmaker(sessionmaker(bind=self.engine))
         self.session = Session()

sqlalchemy_mptt/tests/test_events.py

@@ -12,7 +12,10 @@
 
 import unittest
 
-from sqlalchemy import Boolean, Column, Integer
+from sqlalchemy import Column, Boolean, Integer
+from sqlalchemy.orm import mapper
+from sqlalchemy.event import contains
+from sqlalchemy_mptt.events import TreesManager
 from sqlalchemy.ext.declarative import declarative_base
 
 from . import TreeTestingMixin
@@ -51,3 +54,40 @@ class TestTree(TreeTestingMixin, unittest.TestCase):
 class TestTreeWithCustomId(TreeTestingMixin, unittest.TestCase):
     base = Base
     model = TreeWithCustomId
+
+
+class Events(object):
+
+    def test_register(self):
+        from sqlalchemy_mptt import BaseNestedSets
+        tree_manager = TreesManager(BaseNestedSets)
+        tree_manager.register_mapper(mapper)
+        self.assertTrue(contains(BaseNestedSets, 'before_insert',
+                                 tree_manager.before_insert))
+        self.assertTrue(contains(BaseNestedSets, 'before_update',
+                                 tree_manager.before_update))
+        self.assertTrue(contains(BaseNestedSets, 'before_delete',
+                                 tree_manager.before_delete))
+
+    def test_register_and_remove(self):
+        from sqlalchemy_mptt import BaseNestedSets
+        tree_manager = TreesManager(BaseNestedSets)
+        tree_manager.register_mapper(mapper)
+        tree_manager.register_mapper(mapper, remove=True)
+        self.assertFalse(contains(BaseNestedSets, 'before_insert',
+                                  tree_manager.before_insert))
+        self.assertFalse(contains(BaseNestedSets, 'before_update',
+                                  tree_manager.before_update))
+        self.assertFalse(contains(BaseNestedSets, 'before_delete',
+                                  tree_manager.before_delete))
+
+    def test_remove(self):
+        from sqlalchemy_mptt import BaseNestedSets
+        tree_manager = TreesManager(BaseNestedSets)
+        tree_manager.register_mapper(mapper, remove=True)
+        self.assertFalse(contains(BaseNestedSets, 'before_insert',
+                                  tree_manager.before_insert))
+        self.assertFalse(contains(BaseNestedSets, 'before_update',
+                                  tree_manager.before_update))
+        self.assertFalse(contains(BaseNestedSets, 'before_delete',
+                                  tree_manager.before_delete))