deal with overridden getattr etc.

thomasballinger · thomasballinger · commit fb3dc2280595 · 2015-12-25T12:10:51.000-08:00
diff --git a/bpython/simpleeval.py b/bpython/simpleeval.py
@@ -30,11 +30,12 @@
 
 import ast
 from six import string_types
+import inspect
 from six.moves import builtins
 
 from bpython import line as line_properties
 from bpython._py3compat import py3
-from bpython.inspection import is_new_style
+from bpython.inspection import is_new_style, AttrCleaner
 
 _string_type_nodes = (ast.Str, ast.Bytes) if py3 else (ast.Str,)
 _numeric_types = (int, float, complex) + (() if py3 else (long,))
@@ -239,11 +240,12 @@ def evaluate_current_attribute(cursor_offset, line, namespace=None):
 def safe_get_attribute(obj, attr):
     """Gets attributes without triggering descriptors on new-style clases"""
     if is_new_style(obj):
-        result = safe_get_attribute_new_style(obj, attr)
-        if isinstance(result, member_descriptor):
-            # will either be the same slot descriptor or the value
-            return getattr(obj, attr)
-        return result
+        with AttrCleaner(obj):
+            result = safe_get_attribute_new_style(obj, attr)
+            if isinstance(result, member_descriptor):
+                # will either be the same slot descriptor or the value
+                return getattr(obj, attr)
+            return result
     return getattr(obj, attr)
 
 
@@ -264,16 +266,12 @@ def safe_get_attribute_new_style(obj, attr):
     """
     if not is_new_style(obj):
         raise ValueError("%r is not a new-style class or object" % obj)
-    to_look_through = (obj.mro()
-                       if hasattr(obj, 'mro')
-                       else [obj] + type(obj).mro())
+    to_look_through = (obj.__mro__
+                       if inspect.isclass(obj)
+                       else (obj,) + type(obj).__mro__)
 
-    found_in_slots = hasattr(obj, '__slots__') and attr in obj.__slots__
     for cls in to_look_through:
         if hasattr(cls, '__dict__') and attr in cls.__dict__:
             return cls.__dict__[attr]
 
-    if found_in_slots:
-        return AttributeIsEmptySlot
-
     raise AttributeError()
diff --git a/bpython/test/test_simpleeval.py b/bpython/test/test_simpleeval.py
@@ -162,6 +162,24 @@ def s4(self):
         raise AssertionError('Property __get__ executed')
 
 
+class OverridenGetattr(object):
+    def __getattr__(self, attr):
+        raise AssertionError('custom __getattr__ executed')
+    a = 1
+
+
+class OverridenGetattribute(object):
+    def __getattribute__(self, attr):
+        raise AssertionError('custom __getattrribute__ executed')
+    a = 1
+
+
+class OverridenMRO(object):
+    def __mro__(self):
+        raise AssertionError('custom mro executed')
+    a = 1
+
+
 member_descriptor = type(Slots.s1)
 
 
@@ -218,5 +236,17 @@ def test_lookup_with_property_and_slots(self):
                           Slots.__dict__['s3'])
         self.assertIsInstance(sga(SlotsSubclass, 's3'), property)
 
+    def test_lookup_on_overriden_methods(self):
+        sga = safe_get_attribute
+        self.assertEqual(sga(OverridenGetattr(), 'a'), 1)
+        self.assertEqual(sga(OverridenGetattribute(), 'a'), 1)
+        self.assertEqual(sga(OverridenMRO(), 'a'), 1)
+        with self.assertRaises(AttributeError):
+            sga(OverridenGetattr(), 'b')
+        with self.assertRaises(AttributeError):
+            sga(OverridenGetattribute(), 'b')
+        with self.assertRaises(AttributeError):
+            sga(OverridenMRO(), 'b')
+
 if __name__ == '__main__':
     unittest.main()
