Misleading description of PartialEq derived implementation for enums in docs

[nirvana-msu]

Current docs on PartialEq derive state:

When derived on enums, each variant is equal to itself and not equal to the other variants.

I interpret the above statement as "PartialEq compares enum discriminants", which is not the case.

This is true for enums variants with no data, however for enum variants that are struct-like or tuple struct-like, derived PartialEq actually compares the fields (which is expected) and not just discriminants:
https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=64530ce03a4506d1e82a1df4d78765ff

[eggyal]

@rustbot label: +A-docs +C-cleanup +E-easy +T-libs-api

[eggyal]

@rustbot claim