Use additional vars when templating included file names

Fixes #9669

lib/ansible/playbook/play.py

@@ -619,8 +619,14 @@ class Play(object):
                 dirname = self.basedir
                 if original_file:
                     dirname = os.path.dirname(original_file)
-                include_file = template(dirname, tokens[0], mv)
+
+                # temp vars are used here to avoid trampling on the existing vars structures
+                temp_vars = utils.merge_hash(self.vars, self.vars_file_vars)
+                temp_vars = utils.merge_hash(temp_vars, mv)
+                temp_vars = utils.merge_hash(temp_vars, self.playbook.extra_vars)
+                include_file = template(dirname, tokens[0], temp_vars)
                 include_filename = utils.path_dwim(dirname, include_file)
+
                 data = utils.parse_yaml_from_file(include_filename, vault_password=self.vault_password)
                 if 'role_name' in x and data is not None:
                     for y in data: