gh-132717: argparse: Call the convert function for default values of variadic arguments
#132724
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mpkocher
reviewed
Jun 27, 2025
| setattr(namespace, action.dest, | ||
| self._get_value(action, action.default)) | ||
| elif (action.nargs not in (OPTIONAL, None) and | ||
| isinstance(action.default, (list, tuple)) and |
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This seems like it's going to create issues. What is so special about list and tuple? What about set, deque, etc..?
The design of argparse is very loose. I suspect "fixing" this without breaking backwards compatibility might be challenging.
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Hey — thanks for the PR! Unfortunately, changing this behavior is likely to break existing user code. Much of argparse’s design, quirks included, has been stable for a long time, so even seemingly simple changes can have pretty widespread impact. I think we'd be better off clarifying this behaviour in the docs. |
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nargsvalues #132717