devtools::check() will miss package dependency if respective code only appears in function arguments

[ramiromagno]

Using {devtools} version 2.4.4..

Assume a vanilla package (no Imports whatsoever in DESCRIPTION) with only one source R file with one function only:

#' Star wars dataset
#'
#' @param x A data frame.
#'
#' @export
star_wars <- function(x = dplyr::starwars) {
  print(x)
}

devtools::check() will be oblivious to the dependency on {dplyr}:

── R CMD check results ──────────────────────────────────────────────────────────────────────────── weird 0.1.0 ────
Duration: 7.9s

0 errors ✔ | 0 warnings ✔ | 0 notes ✔

R CMD check succeeded

If I try to include this dependency, then I get:

── R CMD check results ──────────────────────────────────────────────────────────────────────────── weird 0.1.0 ────
Duration: 7.8s

❯ checking dependencies in R code ... NOTE
  Namespace in Imports field not imported from: ‘dplyr’
    All declared Imports should be used.

0 errors ✔ | 0 warnings ✔ | 1 note ✖

[jennybc]

What you are noticing is behaviour, admittedly sort of unexpected and quirky, of R CMD check, not of devtools::check(). So it's not something we will or can fix.

There are ways to suppress this NOTE, which I've recorded here (and this was a good nudge for us to include this content in the R Packages book):

hadley/r-pkgs#828

[ramiromagno]

Thanks Jenny!

[moodymudskipper]

FWIW I've reported it to r-devel and it's fixed in dev so should not be an issue from 4.3 onwards