Template play vars after reading them

Fixes #9242

lib/ansible/playbook/play.py

@@ -84,6 +84,11 @@ class Play(object):
         if self.playbook.inventory.src() is not None:
             self.vars['inventory_file'] = self.playbook.inventory.src()
 
+        # template the play vars with themselves and the extra vars
+        # from the playbook, to make sure they're correct
+        all_vars = utils.combine_vars(self.vars, self.playbook.extra_vars)
+        self.vars = template(basedir, self.vars, all_vars)
+
         # We first load the vars files from the datastructure
         # so we have the default variables to pass into the roles
         self.vars_files = ds.get('vars_files', [])