(address . bug-guix@gnu.org)
This is either an R or Guix bug, but from the discussion at https://community.rstudio.com/t/incomplete-final-line-found-whats-the-big-deal/56536,I infer that files should generally end in a newline anyway.
My bug: every time I start R, I get the following warning, which is unpleasant.
Warning message:
In readLines("/etc/timezone") :
incomplete final line found on '/etc/timezone'