[LINT_BUG]: Objects exported from packages and functions run in purrr::map causes lint errors

[vibalre]

box.linters version

0.10.0

Sample source code to lint

# module.R
#' @export
my_constant <- 42

#' @export
my_function <- function(x) {
  x >= 1
}

# object.R
box::use(
  dplyr[storms],
  purrr[map, map_chr],
  stringr[str_to_upper],
)

box::use(
  . / module[my_constant, my_function],
)

#' @export
my_names <-
  map_chr(
    names(storms),
    str_to_upper
  )

#' @export
my_new_constant <- my_constant / 3

#' @export
my_answer <- map(c(1, 2, 3), my_function)

Lint command used

lintr::lint(
    "object.R",
    linters = lintr::linters_with_defaults(defaults = box.linters::rhino_default_linters)
)

Lint result

Line 2[box_pkg_fun_exists_linter] Function not exported by package.
Line 2[box_unused_attached_pkg_fun_linter] Imported function unused.
Line 4[box_unused_attached_pkg_fun_linter] Imported function unused.

Expected result

There should be no lint errors.

[radbasa]

@jakubnowicki I think I know what's going on here. Or rather, what's not going on.

A data object from a package is being imported. We currently use getNamespaceExports() to determine what functions a package exports. This does not return data objects.

And because the unused attached package function linter assumes all the attached objects from a package are function, it is complaining that storm() is not used.

The unused str_to_upper is the same. The linter is looking for a function token with the name str_to_upper. The str_to_upper in the map_chr() call is a plain object token.

Issue 1 will need to wait for the full support for box namespace exports from {box}.

Issue 2 and 3 can be handled within the linter functions.

[radbasa]

Issues 2 and 3 handled by PR 128.

Leaving this issue open for issue 1.