- Fixed an issue where a particular base class within utils

didn't implement ``__slots__``, and therefore meant all subclasses
of that class didn't either, negating the rationale for ``__slots__``
to be in use.  Didn't cause any issue except on IronPython
which apparently does not implement ``__slots__`` behavior compatibly
with cPython.
Fixes #3494

1 files changed, 29 insertions, 1 deletions

diff --git a/test/base/test_utils.py b/test/base/test_utils.py
index 256f52850..8074de53e 100644
--- a/test/base/test_utils.py
+++ b/test/base/test_utils.py
@@ -2,13 +2,14 @@ import copy
 
 from sqlalchemy import util, sql, exc, testing
 from sqlalchemy.testing import assert_raises, assert_raises_message, fixtures
-from sqlalchemy.testing import eq_, is_, ne_, fails_if
+from sqlalchemy.testing import eq_, is_, ne_, fails_if, mock
 from sqlalchemy.testing.util import picklers, gc_collect
 from sqlalchemy.util import classproperty, WeakSequence, get_callable_argspec
 from sqlalchemy.sql import column
 from sqlalchemy.util import langhelpers
 import inspect
 
+
 class _KeyedTupleTest(object):
 
     def _fixture(self, values, labels):
@@ -284,6 +285,33 @@ class MemoizedAttrTest(fixtures.TestBase):
         eq_(f1.bar(), 20)
         eq_(val[0], 21)
 
+    def test_memoized_slots(self):
+        canary = mock.Mock()
+
+        class Foob(util.MemoizedSlots):
+            __slots__ = ('foo_bar', 'gogo')
+
+            def _memoized_method_gogo(self):
+                canary.method()
+                return "gogo"
+
+            def _memoized_attr_foo_bar(self):
+                canary.attr()
+                return "foobar"
+
+        f1 = Foob()
+        assert_raises(AttributeError, setattr, f1, "bar", "bat")
+
+        eq_(f1.foo_bar, "foobar")
+
+        eq_(f1.foo_bar, "foobar")
+
+        eq_(f1.gogo(), "gogo")
+
+        eq_(f1.gogo(), "gogo")
+
+        eq_(canary.mock_calls, [mock.call.attr(), mock.call.method()])
+
 
 class ToListTest(fixtures.TestBase):
     def test_from_string(self):