I'm confused by the presence of two promises for each file.  What does that even mean ?
If one of these were conditioned on some sort of first-pass check and the other on its negation, I could make sense of it.

I'm confused by deleting a line with $(sys.fqhost) in it, which sounds kinda random - depending on where we run the test - or does the test infrastructure somehow rig sys.fqhost to be a fixed string independent of reality ?