Error when applying contrasts to grouping variable in `grouped_df`

[tsostarics]

library(contrastable)
data.frame(v1 = c('a','b','c')) |> 
  dplyr::group_by(v1) |> 
  contrastable::enlist_contrasts(v1 ~ treatment_code)

Converting to factors: v1
Error in `dplyr::mutate()`:
! Problem while computing `..1 = dplyr::across(dplyr::all_of(which_to_factors), factor)`.
ℹ The error occurred in group 0: character(0).
Caused by error in `across()`:
! Can't subset columns that don't exist.
✖ Column `v1` doesn't exist.

Error from the internal mutate call comes from attempting to set contrasts on a grouping column in a dataframe. Options to fix:

• Force ungroup on the dataframe before passing to mutate, add message that this is happening
• Add more helpful error message telling user to ungroup the factors they're attempting to set contrasts to
• Drop grouping columns that the user is trying to set, but keep grouping columns not involved in contrast functions (less overbearing but more involved than just ungroup)
• Force ungroup before passing to mutate, but then regroup after applying contrasts (needs intermediate step to save grouping column names)

[tsostarics]

Revisiting this, it seems like dropping the dplyr implementation a while ago inadvertently fixed this.