only forward common args that were given, stop forwarding _args_given

cli_function.py

@@ -162,7 +162,6 @@ class CliFunction:
         Resolve default arguments from the config file and CLI param defaults.
 
         Add an extra _args_given argument which determines if an argument was given or not.
-        If _args_given is already present in kwargs, preserve it.
         '''
         args_with_defaults = kwargs.copy()
         # Add missing args from config file.
@@ -198,10 +197,7 @@ class CliFunction:
                     args_with_defaults[key] = argument.default
                 else:
                     raise Exception('Value not given for mandatory argument: ' + key)
-        if '_args_given' in kwargs:
-            args_with_defaults['_args_given'] = kwargs['_args_given']
-        else:
-            args_with_defaults['_args_given'] = args_given
+        args_with_defaults['_args_given'] = args_given
         if 'config_file' in args_with_defaults:
             del args_with_defaults['config_file']
         return args_with_defaults

common.py

@@ -682,7 +682,9 @@ Valid emulators: {}
         and are all defined in this class instead of in the derived class
         of the script.
         '''
-        return {key:self.env[key] for key in self._common_args | {'_args_given'}}
+        return {
+            key:self.env[key] for key in self._common_args if self.env['_args_given'][key]
+        }
 
     def get_stats(self, stat_re=None, stats_file=None):
         if stat_re is None: