[R-pkg-devel] About a need for hooks from R CMD ... commands, and a question

[Dirk Eddelbuettel]

On 4 January 2019 at 19:24, Iñaki Ucar wrote:
| On Fri, 4 Jan 2019 at 16:43, Dirk Eddelbuettel <edd using debian.org> wrote:
| >
| >
| > For a few years now I had mused about how nice it would be to have other
| > scripts triggered like `cleanup`.  For Rcpp, it would be nice to run
| > compileAttributes(). For roxygen2, it would be nice to run roxygenize()
| > (especially if that continued to work the way it did, but I digress).
| > That was mostly a "wouldn't it be nice" question and not that urgent as I
| > wrote myself littler scripts for most tasks anyway.
| >
| > But I now have a related problem at work. We are authoring C++ libraries and
| > R packages 'mono-repo' style. And I need to reference builds of the R
| > packages back to the repo branches / repo directories used where R CMD build
| > ran in a branch -- in order to at R CMD INSTALL time access the matching
| > header files and libraries from that branch.  I do not see an obvious way of
| > encoding this in the .tar.gz created by the R CMD build step. The best I can
| > think of is creating binaries via R CMD INSTALL --build instead of creating
| > source tarballs.
| >
| > Is there something better I am missing? Any hacks, hints, or ideas?
| 
| I'm not sure whether I understand correctly what you are trying to
| achieve. Isn't generating a custom configure script enough for your
| needs?

That is what I thought yesterday when I wrote / updated and tested those.
They work great when you install from source as they have access to shell's
${PWD} and R's getwd().

But when you run R CMD build, (essentially) just cleanup and a tar are
running. No other code. Hence my Subject: here -- a need for a hook.

Once you have built a .tar.gz and run R CMD INSTALL on it, R goes off to
_another temporary directory_ and while configure may be running ... you are
no longer in the directory you called it from. So I have now lost the
connection to the particular variant of headers and libraries I may have had
in that branch.

Doing R CMD INSTALL --build ... is a workaround.  But it still would be nice
to have an explicit hook.

Hope this explains it better, and thanks for the follow-up.

Dirk

-- 
http://dirk.eddelbuettel.com | @eddelbuettel | edd using debian.org