Use of deprecated ast.Object

[cbandy]

cmd/errtrace uses ast.Object which was deprecated in Go 1.22. Discussed here: https://go.dev/issue/52463

[abhinav]

Yeah, we'll need to switch to go/types for the auto-instrumenter.

[prashantv]

errtrace uses ast.Object in a pretty limited way: to resolve identifiers to named returns (within the same function). Using go/types seems heavier, and not sure how well it works when resolving single files (e.g., for errtrace -w <file.go>.

The partial object resolution is all we need, and seems like the functionality isn't going away, but is marked deprecated to help guard against misuse. From the issue:

It is true that, potentially, using the partial object resolution in go/ast is fine for some use cases. Perhaps they only deal with very simple Go code that doesn't run into any of the limitations against go/types. I think it should be fine for those (hopefully very rare) cases to consciously ignore the deprecation notice.

Is the errtrace use-case impacted by any of the limitations? If not, I'm wondering whether switching to go/types will be worthwhile.