Uninformative error when leaving an empty @param

[pierrecamilleri]

Hi,
Leaving an empty #' @param in a roxygen comment leads to an error with no information at all to identify the problem:
Error in FUN(X[[i]], ...) : index out of bound

I believe it could be useful to specify in which comment the error occurs in such situations.

[hadley]

Minimal reprex:

library(roxygen2)
roc_proc_text(rd_roclet(), "
  #' Title
  #' @param
  #'
  #' @export
  foo <- function() {}"
)
#> Error in FUN(X[[i]], ...): subscript out of bounds

^{Created on 2019-07-25 by the reprex package (v0.3.0)}