Pass custom help formatter to subparsers (#336) (#339)

* Pass custom help formatter to subparsers (#336)

* Fix formatting in field_wrapper.py

Signed-off-by: Fabrice Normandin <[email protected]>

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Signed-off-by: Fabrice Normandin <[email protected]>
Co-authored-by: Fabrice Normandin <[email protected]>

Author: zrlf

simple_parsing/wrappers/field_wrapper.py

@@ -1021,7 +1021,7 @@ def add_subparsers(self, parser: ArgumentParser):
         # subparsers.required = default_value is dataclasses.MISSING
         for subcommand, dataclass_type in self.subparsers_dict.items():
             logger.debug(f"adding subparser '{subcommand}' for type {dataclass_type}")
-            subparser = subparsers.add_parser(subcommand)
+            subparser = subparsers.add_parser(subcommand, formatter_class=parser.formatter_class)
             # Just for typing correctness, as we didn't explicitly change
             # the return type of subparsers.add_parser method.)
             subparser = cast("ArgumentParser", subparser)