check_dots_empty() and missing arguments

[krlmlr]

Can we support the "trailing comma" idiom with check_dots_empty(), the same way as we do in list() ?

fun <- function(..., a = NULL) {
  rlang::check_dots_empty()
}

# Expected
fun(1)
#> Error in `fun()`:
#> ! `...` must be empty.
#> x Problematic argument:
#> • ..1 = 1
#> ℹ Did you forget to name an argument?

# Expected
fun(a = 1)
#> NULL

# Unexpected
fun(
  a = 1,
)
#> Error in `fun()`:
#> ! `...` must be empty.
#> x Problematic argument:
#> • ..1 = <empty>
#> ℹ Did you forget to name an argument?

^{Created on 2022-04-19 by the reprex package (v2.0.1)}

[lionel-]

hmm I don't see why not. Any objections to this @hadley?

[hadley]

Seems fine to me.