I'm developing my first R package (using R 2.13, Ubuntu 10.10). Let's call it foo and let's say that the code in the R/ directory begins with the line library(bar), where bar is an existing package in CRAN, on which foo depends. My DESCRIPTION file contains the line:
Depends: bar
When package foo is ready for testing, I install it locally using:
R CMD INSTALL foo_1.0.tar.gz
However, if bar is not installed, I see:
ERROR: dependency ‘bar’ is not available for package ‘foo’
Obviously, if my foo were installed from CRAN using install.packages(), bar would be installed at the same time. So my question is: how can I ensure that CRAN package bar is installed, if required, when I install my package foo using R CMD INSTALL? Is this a job for a configuration script?
Actually, re-reading the R extensions guide, it doesn't say that R CMD INSTALL will get dependencies from CRAN. The install.packages() method from within R will do that, but at first glance I don't think R CMD INSTALL does.
You can use install.packages to install from a .tar.gz, but you have to set repos=NULL, and then this applies:
dependencies: logical indicating to also install uninstalled packages
on which these packages depend/suggest/import (and so on
recursively). Not used if repos = NULL.
I suspect the thing to do is to get the dependencies out of the DESCRIPTION file and then run R and do an install.packages() on those when you are testing your build in a clean environment.