Make `add_tally()` S3 generic?

[etiennebacher]

count(), add_count(), and tally() are generics but add_tally() is not:

sloop::is_s3_generic("count", env = getNamespace("dplyr"))
#> [1] TRUE
sloop::is_s3_generic("add_count", env = getNamespace("dplyr"))
#> [1] TRUE
sloop::is_s3_generic("tally", env = getNamespace("dplyr"))
#> [1] TRUE
sloop::is_s3_generic("add_tally", env = getNamespace("dplyr"))
#> [1] FALSE

Is it possible to make add_tally() generic?

It looks like this was already planned in #3739 but add_tally() was forgotten.

[etiennebacher]

Sorry for the "bump"-like comment, but it seems that dplyr will get a new release soon-ish so I'm wondering if this issue could make it in the list of new features. It seems to be an omission from #3739 so I suppose there shouldn't be any concern regarding the stability of add_tally().