Fix an issue around __dir__ in the interpreter

Fixes #1027.

jedi/evaluate/compiled/context.py

@@ -305,20 +305,21 @@ class CompiledObjectFilter(AbstractFilter):
             name,
             lambda: self._compiled_object.access_handle.is_allowed_getattr(name),
             lambda: self._compiled_object.access_handle.dir(),
+            check_has_attribute=True
         )
 
-    def _get(self, name, allowed_getattr_callback, dir_callback):
+    def _get(self, name, allowed_getattr_callback, dir_callback, check_has_attribute=False):
         """
         To remove quite a few access calls we introduced the callback here.
         """
         has_attribute, is_descriptor = allowed_getattr_callback()
-        if not has_attribute:
+        if check_has_attribute and not has_attribute:
             return []
 
         # Always use unicode objects in Python 2 from here.
         name = force_unicode(name)
 
-        if is_descriptor:
+        if is_descriptor or not has_attribute:
             return [self._get_cached_name(name, is_empty=True)]
 
         if self._is_instance and name not in dir_callback():

test/test_api/test_interpreter.py

@@ -298,3 +298,27 @@ def test_repr_execution_issue():
     d, = script.goto_definitions()
     assert d.name == 'ErrorRepr'
     assert d.type == 'instance'
+
+
+def test_dir_magic_method():
+    class CompleteAttrs(object):
+        def __getattr__(self, name):
+            if name == 'foo':
+                return 1
+            if name == 'bar':
+                return 2
+            raise AttributeError(name)
+
+        def __dir__(self):
+            return ['foo', 'bar'] + object.__dir__(self)
+
+    itp = jedi.Interpreter("ca.", [{'ca': CompleteAttrs()}])
+    completions = itp.completions()
+    names = [c.name for c in completions]
+    assert '__dir__' in names
+    assert '__eq__' in names
+    assert 'foo' in names
+    assert 'bar' in names
+
+    foo = [c for c in completions if c.name == 'foo'][0]
+    assert foo._goto_definitions() == []