RStan: what's rstan/rstan/R/git_rstan_head.R

What does this do?

I noticed on my branch, not only did it change, it added a whole bunch of new lines. I’m not sure what this is supposed to have.

It doesn’t really do much. If you install via make install it causes the SHA of the last commit to appear when the package is loaded.

Ok. I was typing make install a lot.

Should it always only have one line? If so, I can edit the file by hand.

It doesn’t really matter since whatever is the last line gets used.