In this particular case, I don't think adding a null input guard would meet the minimum level of copyrightability (the same way you can't actually copyright "he

In this particular case, I don't think adding a null input guard would meet the minimum level of copyrightability (the same way you can't actually copyright "hello world" or basic shapes). The barrier for that sort of thing is really low, but copyright does have an exemption for stuff like that. (Upd: Looked at the PR in other comments; yeah I don't think the null guard meets copyrightability, but I Am Not A Lawyer. The attached test case might be more dubious.)