instrumented collection fires append/delete events inappropriately when assigning collection slices

[Mike Bayer]

Index: test/orm/collection.py
===================================================================
--- test/orm/collection.py      (revision 3659)
+++ test/orm/collection.py      (working copy)
@@ -274,10 +274,35 @@
             self.assert_(e4 not in canary.data)
             self.assert_(e3 in canary.data)

+    def _test_list_slice(self, typecallable, creator=entity_maker):
+        class Foo(object):
+            pass
+        canary = Canary()
+        manager.register_class(Foo)
+        manager.register_attribute(Foo, 'attr', True, extension=canary,
+                                   typecallable=typecallable)
+        
+        obj = Foo()
+        e1 = creator()
+        e2 = creator()
+        e3 = creator()
+        obj.attr = [e2, e3](e1,)
+        assert e1 in canary.added
+        assert e2 in canary.added
+        assert e3 in canary.added
+
+        obj.attr = obj.attr[1:](1:)
+        assert e1 in canary.removed
+        assert e2 in canary.added
+        assert e3 in canary.added
+        assert e2 not in canary.removed
+        assert e3 not in canary.removed
+
     def test_list(self):
         self._test_adapter(list)
         self._test_list(list)
         self._test_list_bulk(list)
+        self._test_list_slice(list)

     def test_list_subclass(self):
         class MyList(list):

[Mike Bayer]

heres an ORM test that can go into test/orm/cascade.py:

from sqlalchemy import *
from sqlalchemy.orm import *

engine = create_engine('sqlite://', echo=True)

meta = MetaData(engine)

a = Table('a', meta, Column('id', Integer, primary_key=True), Column('foo', String(30)))
b = Table('b', meta, Column('id', Integer, primary_key=True), Column('foo', String(30)), Column('a_id', Integer, ForeignKey('a.id')))

class A(object):
    def __init__(self, foo):
        self.foo = foo
class B(object):
    def __init__(self, foo):
        self.foo = foo

mapper(A, a, properties={
    'bs':relation(B, cascade="all, delete-orphan")
})
mapper(B, b)

meta.create_all()

a1 = A('a1')
a1.bs.append(B('b1'))
a1.bs.append(B('b2'))
a1.bs.append(B('b3'))

sess = create_session()
sess.save(a1)
sess.flush()

assert b.count(b.c.a_id == None).scalar() == 0

assert b.count().scalar() == 3

a1 = sess.query(A).get(a1.id)
assert len(a1.bs) == 3
a1.bs = list(a1.bs)
assert not class_mapper(B)._is_orphan(a1.bs[0](0))
a1.bs[0](0).foo='b2modified'
a1.bs[1](1).foo='b3modified'
sess.flush()

assert b.count().scalar() == 3

[jek]

2d3f907ac0a23d410ecc3c74afc6d63bd2abc186

[Mike Bayer]

Removing milestone: 0.4.xx (automated comment)