Fix incorrect error message for arguments with choices

knack/parser.py

@@ -30,6 +30,20 @@
 ]
 
 
+def _get_action_name(argument):
+    # copied from argparse in order not to use a protected method
+    if argument is None:
+        return None
+    if argument.option_strings:
+        return '/'.join(argument.option_strings)
+    if argument.metavar not in (None, argparse.SUPPRESS):
+        return argument.metavar
+    if argument.dest not in (None, argparse.SUPPRESS):
+        return argument.dest
+
+    return None
+
+
 class CLICommandParser(argparse.ArgumentParser):
 
     @staticmethod
@@ -266,19 +280,34 @@ def _check_value(self, action, value):
         import sys
 
         if action.choices is not None and value not in action.choices:
-            # parser has no `command_source`, value is part of command itself
-            error_msg = "{prog}: '{value}' is not in the '{prog}' command group. See '{prog} --help'.".format(
-                prog=self.prog, value=value)
-            logger.error(error_msg)
-            candidates = difflib.get_close_matches(value, action.choices, cutoff=0.7)
+            is_command = action.dest in ["_command", "_subcommand"]
+            candidates = action.choices
+            if is_command:
+                candidates = difflib.get_close_matches(value, action.choices, cutoff=0.7)
+
             if candidates:
                 print_args = {
                     's': 's' if len(candidates) > 1 else '',
                     'verb': 'are' if len(candidates) > 1 else 'is',
-                    'value': value
+                    'value': value,
+                    'action': _get_action_name(action),
+                    'choices': ', '.join(map(repr, candidates))
                 }
-                suggestion_msg = "\nThe most similar choice{s} to '{value}' {verb}:\n".format(**print_args)
+
+            if is_command:
+                # parser has no `command_source`, value is part of command itself
+                error_msg = "{prog}: '{value}' is not in the '{prog}' command group. See '{prog} --help'.".format(
+                    prog=self.prog, value=value)
+                logger.error(error_msg)
+                if candidates:
+                    suggestion_msg = "\nThe most similar choice{s} to '{value}' {verb}:\n".format(**print_args)
+                    suggestion_msg += '\n'.join(['\t' + candidate for candidate in candidates])
+                    print(suggestion_msg, file=sys.stderr)
+            else:
+                error_msg = "{prog}: invalid choice '{value}'. See '{prog} --help'.".format(
+                    prog=self.prog, value=value)
+                logger.error(error_msg)
+                suggestion_msg = "\nPossible choice{s} for argument '{action}' {verb}:\n".format(**print_args)
                 suggestion_msg += '\n'.join(['\t' + candidate for candidate in candidates])
                 print(suggestion_msg, file=sys.stderr)
-
             self.exit(2)