Move is_side_effect to Definition and correct bugs

jedi/api/classes.py

@@ -523,16 +523,6 @@ class BaseDefinition(object):
         """
         return self._name.infer().get_type_hint()
 
-    def is_side_effect(self):
-        """
-        Checks if a name is defined as ``self.foo = 3``. In case of self, this
-        function would return False, for foo it would return True.
-        """
-        tree_name = self._name.tree_name
-        if tree_name is None:
-            return False
-        return tree_name.parent.type == 'trailer'
-
 
 class Completion(BaseDefinition):
     """
@@ -717,6 +707,16 @@ class Definition(BaseDefinition):
         else:
             return self._name.tree_name.is_definition()
 
+    def is_side_effect(self):
+        """
+        Checks if a name is defined as ``self.foo = 3``. In case of self, this
+        function would return False, for foo it would return True.
+        """
+        tree_name = self._name.tree_name
+        if tree_name is None:
+            return False
+        return tree_name.is_definition() and tree_name.parent.type == 'trailer'
+
     def __eq__(self, other):
         return self._name.start_pos == other._name.start_pos \
             and self.module_path == other.module_path \

test/test_api/test_names.py

@@ -175,12 +175,15 @@ def test_no_error(get_names):
     'code, index, is_side_effect', [
         ('x', 0, False),
         ('x.x', 0, False),
-        ('x.x', 1, True),
+        ('x.x', 1, False),
-        ('def x(x): x.x', 1, False),
+        ('x.x = 3', 0, False),
-        ('def x(x): x.x', 3, True),
+        ('x.x = 3', 1, True),
+        ('def x(x): x.x = 3', 1, False),
+        ('def x(x): x.x = 3', 3, True),
         ('import sys; sys.path', 0, False),
         ('import sys; sys.path', 1, False),
-        ('import sys; sys.path', 2, True),
+        ('import sys; sys.path', 2, False),
+        ('import sys; sys.path = []', 2, True),
     ]
 )
 def test_is_side_effect(get_names, code, index, is_side_effect):