[R-pkg-team] Bug#901598: dh-r: xvfb-run wrapper missing

[Dirk Eddelbuettel]

Package: dh-r
Version: 120180613
Severity: important

Some CRAN packages for R require x11 at build time when they load the package
towards the end of the 'R CMD build' step. r-cran.mk accomodated that via

## xvfb-run with GL extension and default resolution
xvfbSrvArgs 	= -screen 0 1024x768x24 -ac +extension GLX +render -noreset

[...]

                ## call R to install the sources we're looking at
                ## use this inside xvfb-run if this wrapper is installed
		if test -f /usr/bin/xvfb-run; then 			\
			$(makeFlagsCall) xvfb-run -a -n 20              \
                                                  -s "${xvfbSrvArgs}"   \
				R CMD INSTALL -l $(debRlib) --clean     \
					$(extraInstallFlags) .   	\
					$(builttimeStamp)   	        \
					;                               \
		else							\
			$(makeFlagsCall) R CMD INSTALL -l $(debRlib) 	\
					--clean $(extraInstallFlags) .  \
					$(builttimeStamp)   	        \
					;                               \
		fi

So if xvfb-run is present (in the chroot, say), it is used to wrap the call.
We used that for years.

dh-r skipped that step.

For a package like cairoDevice (aka r-cran-cairodevice), this renders dh-r
unuseable:

** testing if installed package can be loaded
Error: package or namespace load failed for 'cairoDevice':
 .onLoad failed in loadNamespace() for 'cairoDevice', details:
  call: fun(libname, pkgname)
  error: GDK display not found - please make sure X11 is running
Error: loading failed
Execution halted
ERROR: loading failed
* removing '/build/cairodevice-2.25/debian/r-cran-cairodevice/usr/lib/R/site-library/cairoDevice'
dh_auto_install: R CMD INSTALL -l /build/cairodevice-2.25/debian/r-cran-cairodevice/usr/lib/R/site-library --clean . "--built-timestamp='Fri, 15 Jun 2018 05:15:15 -0500'" returned exit code 1
make: *** [debian/rules:7: binary] Error 25
dpkg-buildpackage: error: fakeroot debian/rules binary subprocess returned exit status 2
I: copying local configuration
E: Failed autobuilding of package
I: unmounting dev/ptmx filesystem
I: unmounting dev/pts filesystem
I: unmounting dev/shm filesystem
I: unmounting proc filesystem
I: unmounting sys filesystem
I: cleaning the build env 
I: removing directory /var/cache/pbuilder/build//1441 and its subdirectories
gbp:error: 'pdebuild' failed: it exited with 1

To reproduce, clone the repo at 

   https://salsa.debian.org/edd/r-cran-cairodevice

and use the

   bug/dh-r

branch. The master and debian branch revert back to cdbs by (yuck) including
a copy of r-cran.mk in debian/rules.

Dirk

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