But okay, is it really so much easier to write a test which just tests changing the time signature? It's still going to require doing OCR. And if I'm really testing it, I've got to make sure the time signature change comes at the correct point, which requires OCR on the notes around it. Also the bar lines (to makes sure the time signature change is reflected in the notes per bar and not just by writing a new time signature out and otherwise ignoring it).
Now, it's perfectly reasonable to have unit tests that the code correctly recognizes time signature changes in ABC format. (And it looks like I forgot to write them: I see inline key changes in the tests but not inline time signature changes.) But that's only testing half of the problem; and it's the easier half by far.
But okay, is it really so much easier to write a test which just tests changing the time signature? It's still going to require doing OCR. And if I'm really testing it, I've got to make sure the time signature change comes at the correct point, which requires OCR on the notes around it. Also the bar lines (to makes sure the time signature change is reflected in the notes per bar and not just by writing a new time signature out and otherwise ignoring it).
Now, it's perfectly reasonable to have unit tests that the code correctly recognizes time signature changes in ABC format. (And it looks like I forgot to write them: I see inline key changes in the tests but not inline time signature changes.) But that's only testing half of the problem; and it's the easier half by far.