Move argument grouping into FunctionSchema (#48195)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/48195
The general approach is to change Arguments, splitting `positional`, `kwarg_only` and `out`, into `pre_self_positional`, `self_arg`, `post_self_positional`, and `pre_tensor_options_kwarg_only`, `tensor_options` and `post_tensor_options_kwarg_only`. The splits are as you'd expect: we extract out the self argument and the tensor options arguments, and record the other arguments that came before and after. To do this, we move the logic in `group_arguments` to the parsing process.
Some fuzz in the process:
* I renamed `ThisArgument` to `SelfArgument`, since we don't actually use the terminology "this" outside of C++ (and the model is Python biased)
* I kept the `group_arguments` function, which now just reads out the arguments from the structured model in the correct order. In the long term, we should get rid of this function entirely, but for now I kept it as is to reduce churn.
* I decided to arbitrarily say that when self is missing, everything goes in "post-self", but when tensor options is missing, everything goes in "pre-tensor-options". This was based on where you typically find the argument in question: self is usually at front (so most args are after it), while tensor options are typically at the end (so most args go before it).
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Reviewed By: zhangguanheng66
Differential Revision: D25231166
Pulled By: ezyang
fbshipit-source-id: 25d77ad8319c4ce0bba4ad82e451bf536ef823ad
