> This is exactly what I said.  From the context, I think it's clear that the
> words "path", "to", and "file" don't contain slashes.

If "path" does not contain slashes (with which I agree), concatenating it to file:/// (not file://) is the right thing to do.

Anyway, if the check fails on Cygwin, the only fix is special-casing the test according to system-type. Feel free to do it. No idea whether ms-dos and darwin work with file:/// or file:// or both.