R formula: brew cleanup deletes the site-library folder if it is empty

[pooranis]

I noticed this in installing homebrew-core R 4.2.0 (and earlier versions), but I am not sure if something is going wrong uniquely with me and my situation.

1. As part of installation, the site-library folder gets created in $HOMEBREW_PREFIX/lib/R/4.2/site-library if it doesn't exist (and then is symlinked to $HOMEBREW_PREFIX/Cellar/r/4.2.0/lib/R/site-library so if you upgrade minor version of R can keep previously installed packages ).

2. Then if you happen to run brew cleanup, brew deletes it if it is empty (which if you haven't installed any R pkgs yet, it will be).

   • I'm not sure if this happens by design (?) or is a bug that this particular folder is not preserved or is the fault of something wrong on my end.

3. The next time you want to install a package in R, depending on at what juncture the folder got deleted and your setup, you may get a warning/error that the site-library directory doesn't exist AND/OR it will install to the system library folder $HOMEBREW_PREFIX/Cellar/r/4.2.0/lib/R/library if you don't have a user library directory set up

   • (suboptimal, as you will lose your packages on next minor update - :( happened to me :( ) .

4. If at some point, you have to relink brew unlink r && brew link r because of the previous symlink made in step 1, a link gets created in $HOMEBREW_PREFIX/lib/R/site-library - and it ends up just being a "circular link" - broken.

   • (I've done this many times because I never understood where that site-library folder went and thought it was some symlink problem)

So, now I manually created that $HOMEBREW_PREFIX/lib/R/4.2/site-library folder and put a dummy file in it, so for the period it is empty and I am installing other things, it stays put, but it occurred to me that this shouldn't be happening.