Refactor allowed_getattr_callback a bit to not raise random errors.

jedi/evaluate/compiled/access.py

@@ -275,17 +275,18 @@ class DirectObjectAccess(object):
             return False
 
     def is_allowed_getattr(self, name):
+        # TODO this API is ugly.
         try:
             attr, is_get_descriptor = getattr_static(self._obj, name)
         except AttributeError:
-            raise
+            return False, False
         else:
             if is_get_descriptor \
                     and not type(attr) in ALLOWED_DESCRIPTOR_ACCESS:
                 # In case of descriptors that have get methods we cannot return
                 # it's value, because that would mean code execution.
-                return False
-        return True
+                return True, True
+        return True, False
 
     def getattr(self, name, default=_sentinel):
         try:

jedi/evaluate/compiled/context.py

@@ -310,12 +310,13 @@ class CompiledObjectFilter(AbstractFilter):
         """
         To remove quite a few access calls we introduced the callback here.
         """
-        try:
-            if not allowed_getattr_callback():
-                return [self._get_cached_name(name, is_empty=True)]
-        except AttributeError:
+        has_attribute, is_descriptor = allowed_getattr_callback()
+        if not has_attribute:
             return []
 
+        if is_descriptor:
+            return [self._get_cached_name(name, is_empty=True)]
+
         if self._is_instance and name not in dir_callback():
             return []
         return [self._get_cached_name(name)]