Make islots private.

3 files changed, 7 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index f36a511..08fd892 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,11 +5,13 @@ Change log for the astroid package (used to be astng)
     * `Class.metaclass()` now handles module-level __metaclass__ declaration
       on python 2, and no longer looks at the __metaclass__ class attribute on
       python 3.
+
     * Function nodes can detect if they are decorated with subclasses
       of builtin descriptors when determining their type
       (`classmethod` and `staticmethod`).
 
-    * Add `slots` and `islots` methods to `Class` nodes.
+    * Add `slots` method to `Class` nodes, for retrieving
+      the list of valid slots it defines.
 
 2014-04-30  --  1.1.1
     * `Class.metaclass()` looks in ancestors when the current class
diff --git a/scoped_nodes.py b/scoped_nodes.py
index 88b8642..95d45a5 100644
--- a/scoped_nodes.py
+++ b/scoped_nodes.py
@@ -1136,8 +1136,10 @@ class Class(Statement, LocalsDictNodeNG, FilterStmtsMixin):
                     break
         return klass
 
-    def islots(self):
+    def _islots(self):
         """ Return an iterator with the inferred slots. """
+        if '__slots__' not in self.locals:
+            return
         for slots in self.igetattr('__slots__'):
             # check if __slots__ is a valid type
             for meth in ITER_METHODS:
@@ -1184,4 +1186,4 @@ class Class(Statement, LocalsDictNodeNG, FilterStmtsMixin):
     @cached
     def slots(self):
         """ Return all the slots for this node. """
-        return list(self.islots())
+        return list(self._islots())
diff --git a/test/unittest_scoped_nodes.py b/test/unittest_scoped_nodes.py
index dfcdd00..37ff3be 100644
--- a/test/unittest_scoped_nodes.py
+++ b/test/unittest_scoped_nodes.py
@@ -898,7 +898,6 @@ def g2():
         self.assertIsInstance(first_slots[1], nodes.Const)
         self.assertEqual(first_slots[0].value, "a")
         self.assertEqual(first_slots[1].value, "b")
-        self.assertEqual(list(first.islots()), first_slots)
 
         second_slots = astroid['Second'].slots()
         self.assertEqual(len(second_slots), 1)