fix a very annoying caching problem

jedi/evaluate_representation.py

@@ -469,7 +469,7 @@ class Execution(Executable):
 
         if base.isinstance(Class):
             # There maybe executions of executions.
-            stmts = [Instance(base, self.var_args)]
+            return [Instance(base, self.var_args)]
         elif isinstance(base, Generator):
             return base.iter_content()
         else:

jedi/helpers.py

@@ -13,6 +13,11 @@ def fast_parent_copy(obj):
     new_elements = {}
 
     def recursion(obj):
+        if isinstance(obj, pr.Statement):
+            # Need to set _set_vars, otherwise the cache is not working
+            # correctly, don't know why.
+            obj.get_set_vars()
+
         new_obj = copy.copy(obj)
         new_elements[obj] = new_obj
 

jedi/parsing.py

@@ -408,9 +408,6 @@ class Parser(object):
         stmt.parent = self.top_module
         self._check_user_stmt(stmt)
 
-        # TODO somehow this is important here. But it slows down Jedi, remove!
-        stmt.get_set_vars()
-
         if tok in always_break + not_first_break:
             self._gen.push_last_back()
         return stmt, tok