howto test a package without installation

Look at Hadley Wickham's devtools package.  It is designed with this
sort of thing.  That said, it really is not too difficult to install
as long as you have a working tool chain (which you will need to test
it anyway).

I cound not find it with google and found no "devtools" on this page 
http://had.co.nz/
can you give more details please.

R CMD INSTALL /tmp/sitools
R
require(sitools)

This seems not to be what i want:

$ R CMD INSTALL sitools
* installing to library ?/usr/local/lib/R/site-library?
Error: ERROR: no permission to install to directory ?/usr/local/lib/R/site-library?

R tries to install something in my system. That may confuse my 
debian packagemanagement.

kind regards,

Jonas Stein <news at jonasstein.de>