"Could not find function" in Roxygen examples during CMD check

Question

I'm running a CMD check on a package in RStudio, part of which analyses the @examples in the inline Roxygen documentation.

I'm getting this error:

checking examples ... ERROR
Running examples in ‘packagename-Ex.R’ failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: checkDate
> ### Title: Ensure that a date string is a valid date
> ### Aliases: checkDate
> 
> ### ** Examples
> 
> checkDate("2017-05-06")
Error: could not find function "checkDate"

Within my .R file, the documentation is defined as:

#' Ensure that a date string is a valid date
#'
#' @param dateString A string (eg. "2017-12-04").
#' @return TRUE or FALSE (and a warning if FALSE).
#' @examples
#' checkDate("2017-05-06")
#' checkDate("2017-05-40")

I am using devtools 1.13.2 and roxygen2 6.0.1, both of which I believe to be up-to-date at time of posting.

I have other packages using this same devtools/roxygen2 combination but have never before seen it fail to find a function name in @examples within its scope.

Someone else seems to have experienced something similar as an update to this question, but I can't see that anyone says how to fix it.

Volin

Answer 1

My guess is that you need to #' @export the function in the Roxygen comment, otherwise the function is not exported to the namespace of the package and it cannot be found.

Pentathlon

Thanks. Do you know of any way to include examples in the documentation without making the function public? (for other developers of the package) – Volin

EDIT: I guess this isn't necessary - can just include comments. – Volin

@Serenthia You could try pkg:::function, then you don't have to make the function public. – Pentathlon

With the pkg:::function approach you'll likely receive a warning, and it may stop the package being accepted on CRAN – Unstable

Yes, that is true, could do some trick like do.call(":::", list(pkgname, functionname) to overcome this, but it is not recommended anyway... – Pentathlon