Moved decorators._set_parser_prog() to argparse_custom.set_parser_prog().

Author: kmvanbrunt

cmd2/argparse_custom.py

@@ -291,6 +291,56 @@ def generate_range_error(range_min: int, range_max: float) -> str:
     return err_str
 
 
+def set_parser_prog(parser: argparse.ArgumentParser, prog: str) -> None:
+    """Recursively set prog attribute of a parser and all of its subparsers.
+
+    Does so that the root command is a command name and not sys.argv[0].
+
+    :param parser: the parser being edited
+    :param prog: new value for the parser's prog attribute
+    """
+    # Set the prog value for this parser
+    parser.prog = prog
+    req_args: list[str] = []
+
+    # Set the prog value for the parser's subcommands
+    for action in parser._actions:
+        if isinstance(action, argparse._SubParsersAction):
+            # Set the _SubParsersAction's _prog_prefix value. That way if its add_parser() method is called later,
+            # the correct prog value will be set on the parser being added.
+            action._prog_prefix = parser.prog
+
+            # The keys of action.choices are subcommand names as well as subcommand aliases. The aliases point to the
+            # same parser as the actual subcommand. We want to avoid placing an alias into a parser's prog value.
+            # Unfortunately there is nothing about an action.choices entry which tells us it's an alias. In most cases
+            # we can filter out the aliases by checking the contents of action._choices_actions. This list only contains
+            # help information and names for the subcommands and not aliases. However, subcommands without help text
+            # won't show up in that list. Since dictionaries are ordered in Python 3.6 and above and argparse inserts the
+            # subcommand name into choices dictionary before aliases, we should be OK assuming the first time we see a
+            # parser, the dictionary key is a subcommand and not alias.
+            processed_parsers = []
+
+            # Set the prog value for each subcommand's parser
+            for subcmd_name, subcmd_parser in action.choices.items():
+                # Check if we've already edited this parser
+                if subcmd_parser in processed_parsers:
+                    continue
+
+                subcmd_prog = parser.prog
+                if req_args:
+                    subcmd_prog += " " + " ".join(req_args)
+                subcmd_prog += " " + subcmd_name
+                set_parser_prog(subcmd_parser, subcmd_prog)
+                processed_parsers.append(subcmd_parser)
+
+            # We can break since argparse only allows 1 group of subcommands per level
+            break
+
+        # Need to save required args so they can be prepended to the subcommand usage
+        if action.required:
+            req_args.append(action.dest)
+
+
 class CompletionItem(str):  # noqa: SLOT000
     """Completion item with descriptive text attached.
 

cmd2/cmd2.py

@@ -784,9 +784,7 @@ def _build_parser(
         else:
             raise TypeError(f"Invalid type for parser_builder: {type(parser_builder)}")
 
-        from .decorators import _set_parser_prog
-
-        _set_parser_prog(parser, prog)
+        argparse_custom.set_parser_prog(parser, prog)
 
         return parser
 

cmd2/decorators.py

@@ -192,56 +192,6 @@ def cmd_wrapper(*args: Any, **kwargs: Any) -> Optional[bool]:
     return arg_decorator
 
 
-def _set_parser_prog(parser: argparse.ArgumentParser, prog: str) -> None:
-    """Recursively set prog attribute of a parser and all of its subparsers.
-
-    Does so that the root command is a command name and not sys.argv[0].
-
-    :param parser: the parser being edited
-    :param prog: new value for the parser's prog attribute
-    """
-    # Set the prog value for this parser
-    parser.prog = prog
-    req_args: list[str] = []
-
-    # Set the prog value for the parser's subcommands
-    for action in parser._actions:
-        if isinstance(action, argparse._SubParsersAction):
-            # Set the _SubParsersAction's _prog_prefix value. That way if its add_parser() method is called later,
-            # the correct prog value will be set on the parser being added.
-            action._prog_prefix = parser.prog
-
-            # The keys of action.choices are subcommand names as well as subcommand aliases. The aliases point to the
-            # same parser as the actual subcommand. We want to avoid placing an alias into a parser's prog value.
-            # Unfortunately there is nothing about an action.choices entry which tells us it's an alias. In most cases
-            # we can filter out the aliases by checking the contents of action._choices_actions. This list only contains
-            # help information and names for the subcommands and not aliases. However, subcommands without help text
-            # won't show up in that list. Since dictionaries are ordered in Python 3.6 and above and argparse inserts the
-            # subcommand name into choices dictionary before aliases, we should be OK assuming the first time we see a
-            # parser, the dictionary key is a subcommand and not alias.
-            processed_parsers = []
-
-            # Set the prog value for each subcommand's parser
-            for subcmd_name, subcmd_parser in action.choices.items():
-                # Check if we've already edited this parser
-                if subcmd_parser in processed_parsers:
-                    continue
-
-                subcmd_prog = parser.prog
-                if req_args:
-                    subcmd_prog += " " + " ".join(req_args)
-                subcmd_prog += " " + subcmd_name
-                _set_parser_prog(subcmd_parser, subcmd_prog)
-                processed_parsers.append(subcmd_parser)
-
-            # We can break since argparse only allows 1 group of subcommands per level
-            break
-
-        # Need to save required args so they can be prepended to the subcommand usage
-        if action.required:
-            req_args.append(action.dest)
-
-
 #: Function signatures for command functions that use an argparse.ArgumentParser to process user input
 #: and optionally return a boolean
 ArgparseCommandFuncOptionalBoolReturn = Callable[[CommandParent, argparse.Namespace], Optional[bool]]

tests/test_argparse.py

@@ -290,7 +290,7 @@ def base_helpless(self, args) -> None:
     parser_bar.set_defaults(func=base_bar)
 
     # create the parser for the "helpless" subcommand
-    # This subcommand has aliases and no help text. It exists to prevent changes to _set_parser_prog() which
+    # This subcommand has aliases and no help text. It exists to prevent changes to set_parser_prog() which
     # use an approach which relies on action._choices_actions list. See comment in that function for more
     # details.
     parser_helpless = base_subparsers.add_parser('helpless', aliases=['helpless_1', 'helpless_2'])
@@ -401,7 +401,7 @@ def test_subcommand_invalid_help(subcommand_app) -> None:
 
 
 def test_add_another_subcommand(subcommand_app) -> None:
-    """This tests makes sure _set_parser_prog() sets _prog_prefix on every _SubParsersAction so that all future calls
+    """This tests makes sure set_parser_prog() sets _prog_prefix on every _SubParsersAction so that all future calls
     to add_parser() write the correct prog value to the parser being added.
     """
     base_parser = subcommand_app._command_parsers.get(subcommand_app.do_base)

tests_isolated/test_commandset/test_argparse_subcommands.py

@@ -45,7 +45,7 @@ def base_helpless(self, args) -> None:
     parser_bar.set_defaults(func=base_bar)
 
     # create the parser for the "helpless" subcommand
-    # This subcommand has aliases and no help text. It exists to prevent changes to _set_parser_prog() which
+    # This subcommand has aliases and no help text. It exists to prevent changes to set_parser_prog() which
     # use an approach which relies on action._choices_actions list. See comment in that function for more
     # details.
     parser_helpless = base_subparsers.add_parser('helpless', aliases=['helpless_1', 'helpless_2'])