R devtools: use local dependencies - r

Question

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antonio wants to draw more attention to this question:
Explain what is the proper workflow when you are building two packages, where one depends on the other. What is the correct way to run devtools::check() on the depending-on package?
I want to add a local package dependency using R devtools.
The suggested way to add packages to the package DESCRIPTION file is one of the two functions use_package() and use_dev_package(), from the usethis package. The latter adds a dependency on an in-development package. The function help shows the following prototype:
use_dev_package(package, type = "Imports", remote = NULL)
where remote is
a character string to specify the remote, e.g. ‘"gitlab::jimhester/covr"’, using any syntax supported by the remotes package.
The remotes vignette shows the following
# Local
Remotes: local::/pkgs/testthat
So the command should be along these lines:
use_dev_package(foopack, type = "Imports", remote = "local::<foopack>")
However, what should be the path to the foopack. An absolute one or relative to project dir? The root package directory or the R directory with the code, or perhaps the foopack.tar.gz build?
All attempts failed for me.
Needless to say that, beyond having the local dependency properly listed in the DESCRIPTION file, I need it to be seen by the devtools build & check functions.
Edit
As regards use_dev_package(), I found a solution:
if I use devtools::check(), then the dependency appears in the search path, and use_dev_package() does not complain any more (see answer below).
However, it is still unclear to me what arguments should I use to make a development check() for the main package, in particular when the package has a vignette.
Ideally, I should be able to pass the check with local dependencies by passing cran = FALSE, but this still gives
"Package required but not available".

Answer 1

It seems that I have to check the local dependencies before adding them to the description file.
devtools::check("path/to/foopack")
usethis::use_dev_package("foopack", remote ="local::path/to/foopack")
The paths can be relative or absolute, and even a single colon works.
It might be worth noting that, when I build the main package, I can use the ordinary:
devtools::build()
but, for a successful check, I need to use the remote argument:
devtools::check(remote = TRUE)
I can't see a rationale for restating what is in the DESCRIPTION file, but I do not have enough expertise to say it's a bug.
Let's see what the others say in this regard.
Edit
Unfortunately, it seems that the remote argument above does not apply to vignettes. So, if I add a vignette to the package, checks fail with local packages
Until an actual solution is found, all I can do is (sadly) to ignore vignette checks:
devtools::check(remote = TRUE, vignettes = FALSE)