.ragged default in modify_depth is not correcly evaluated

[cderv]

library(purrr)
x1 <- list(
  list(1),
  list(list(2))
)
# it works as expected
modify_depth(x1, .depth = -1, ~ . + 1, .ragged = TRUE) %>% str()
#> List of 2
#>  $ :List of 1
#>   ..$ : num 2
#>  $ :List of 1
#>   ..$ :List of 1
#>   .. ..$ : num 3

# .ragged should also be TRUE by default here because .depth is negative
modify_depth(x1, .depth = -1, ~ . + 1)
#> Error: List not deep enough

We have an error because value of .ragged is FALSE, because .depth is modified
internally before .ragged is evaluated.

purrr/R/modify.R

Lines 203 to 212 in 977f1fd

	modify_depth.default <- function(.x, .depth, .f, ..., .ragged = .depth < 0) {
	stopifnot(is_integerish(.depth, n = 1))
	if (.depth < 0) {
	.depth <- vec_depth(.x) + .depth
	}
	.f <- as_mapper(.f, ...)
	modify_depth_rec(.x, .depth, .f, ..., .ragged = .ragged)
	}