now raising an exception by default when encountering unparsed arg(s)

Author: fracpete

CHANGES.rst

@@ -1,6 +1,15 @@
 Changelog
 =========
 
+0.0.7 (2023-11-09)
+------------------
+
+- `Plugin.parse_args` now returns any unparsed arguments that were found
+- the `args_to_objects` method now raises an Exception by default when
+  unknown arguments are encountered for a plugin (can be controlled with
+  the `allow_unknown_args` parameter)
+
+
 0.0.6 (2023-10-11)
 ------------------
 

setup.py

@@ -30,7 +30,7 @@ def _read(f):
         '': 'src'
     },
     packages=find_namespace_packages(where='src'),
-    version="0.0.6",
+    version="0.0.7",
     author='Peter Reutemann',
     author_email='fracpete@waikato.ac.nz',
 )

src/seppl/_args.py

@@ -52,7 +52,7 @@ def split_args(args: List[str], handlers: List[str]) -> Dict[str, List[str]]:
     return result
 
 
-def args_to_objects(args: Dict[str, List[str]], valid_plugins: Dict[str, Plugin], allow_global_options: bool = False) -> List[Plugin]:
+def args_to_objects(args: Dict[str, List[str]], valid_plugins: Dict[str, Plugin], allow_global_options: bool = False, allow_unknown_args: bool = False) -> List[Plugin]:
     """
     Instantiates the plugins from the parsed arguments dictionary.
 
@@ -62,6 +62,8 @@ def args_to_objects(args: Dict[str, List[str]], valid_plugins: Dict[str, Plugin]
     :type valid_plugins: dict
     :param allow_global_options: whether global options are allowed (ie options that don't follow a plugin name)
     :type allow_global_options: bool
+    :param allow_unknown_args: whether to allow unknown args (eg typos or unknown plugins)
+    :type allow_unknown_args: bool
     :return: the list of instantiated plugins
     :rtype: list
     """
@@ -75,7 +77,9 @@ def args_to_objects(args: Dict[str, List[str]], valid_plugins: Dict[str, Plugin]
 
         name = args[key][0]
         plugin = copy.deepcopy(valid_plugins[name])
-        plugin.parse_args(args[key][1:])
+        unknown = plugin.parse_args(args[key][1:])
+        if not allow_unknown_args and (len(unknown) > 0):
+            raise Exception("Found unknown argument(s) for plugin '%s': %s" % (plugin.name(), str(unknown)))
         result.append(plugin)
     return result
 

src/seppl/_plugin.py

@@ -4,6 +4,9 @@
 from ._types import classes_to_str
 
 
+UNKNOWN_ARGS = "unknown_args"
+
+
 class Plugin:
     """
     Base class for plugins.
@@ -38,6 +41,7 @@ def _create_argparser(self) -> argparse.ArgumentParser:
             description=self.description(),
             prog=self.name(),
             formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+        parser.add_argument(UNKNOWN_ARGS, nargs=argparse.REMAINDER)
         return parser
 
     def _apply_args(self, ns: argparse.Namespace):
@@ -49,18 +53,19 @@ def _apply_args(self, ns: argparse.Namespace):
         """
         pass
 
-    def parse_args(self, args: List[str]) -> 'Plugin':
+    def parse_args(self, args: List[str]) -> list:
         """
         Parses the command-line arguments.
 
         :param args: the arguments to parse
         :type args: list
-        :return: itself
-        :rtype: Plugin
+        :return: any unknown args
+        :rtype: list
         """
         parser = self._create_argparser()
-        self._apply_args(parser.parse_args(args))
-        return self
+        ns = parser.parse_args(args)
+        self._apply_args(ns)
+        return ns.unknown_args
 
     def print_help(self):
         """