[Rd] Testing R build when using --without-recommended-packages?

[Martin Maechler]

>>>>> Gabriel Becker 
>>>>>     on Tue, 4 May 2021 14:40:22 -0700 writes:

    > Hmm, that's fair enough Ben, I stand corrected.  I will say that this seems
    > to be a pretty "soft" recommendation, as these things go, given that it
    > isn't tested for by R CMD check, including with the -as-cran extensions. In
    > principle, it seems like it could be, similar checks are made in package
    > code for inappropriate external-package-symbol usage/

    > Either way, though, I suppose I have a number of packages which have been
    > invisibly non-best-practices compliant for their entire lifetimes (or at
    > least, the portion of that where they had tests/vignettes...).

    > Best,
    > ~G

    > On Tue, May 4, 2021 at 2:22 PM Ben Bolker <bbolker using gmail.com> wrote:

    >> Sorry if this has been pointed out already, but some relevant text
    >> from
    >> 
    >> https://cran.r-project.org/doc/manuals/r-release/R-exts.html#Suggested-packages
    >> 
    >> > Note that someone wanting to run the examples/tests/vignettes may not
    >> have a suggested package available (and it may not even be possible to
    >> install it for that platform). The recommendation used to be to make
    >> their use conditional via if(require("pkgname")): this is OK if that
    >> conditioning is done in examples/tests/vignettes, although using
    >> if(requireNamespace("pkgname")) is preferred, if possible.
    >> 
    >> ...
    >> 
    >> > Some people have assumed that a ‘recommended’ package in ‘Suggests’
    >> can safely be used unconditionally, but this is not so. (R can be
    >> installed without recommended packages, and which packages are
    >> ‘recommended’ may change.)


Thank you all (Henrik, Gabe, Dirk & Ben) !

I think it would be a good community effort  and worth the time
also of R core to further move into the right direction
as Dirk suggested.

I think we all agree it would be nice if Henrik (and anybody)
could use  'make check' on R's own sources after using
 --without-recommended-packages

Even one more piece of evidence is the   tests/README   file in
the R sources.  It has much more but simply starts with

---------------------------------------------------------------------------
There is a hierarchy of check targets:

     make check

for all builders.  If this works one can be reasonably happy R is working
and do `make install' (or the equivalent).

    make check-devel

for people changing the code: this runs things like the demos and
no-segfault which might be broken by code changes, and checks on the
documentation (effectively R CMD check on each of the base packages).
This needs recommended packages installed.

    make check-all

runs all the checks, those in check-devel plus tests of the recommended
packages.

Note that for complete testing you will need a number of other
......................
......................

---------------------------------------------------------------------------

So, our (R core) own intent has been that   'make check'  should
run w/o rec.packages  but further checking not.

So, yes, please, you are encouraged to send patches against the
R devel trunk  to fix such examples and tests.

Best,
Martin