Inspired by the codecov report, the_update_buttons_checked method of theNapariNavigationToolbar isuntested. So here's a (slightly) dumb UI test.

If anyone knows a better way to compare twoQImages I'm really open to it.

Buuuut itdoes seem like a nestedfor loop is the simplest way to do this. (For reference:there seems to be an unlooping way to shove the data into anumpy array, but it involves pointers, and I'm not sure it's more readable. Readability counts?) Idid check the time and the loopy way in this PR is ones of milliseconds.

Testing:

Things I've done:

• UsedQImage.save to dump the images.
• Replace the quickreturn True with

  print(f"a[{x},{y}] ={a.pixel(x,y)},\t b[{x},{y}] ={b.pixel(x,y)}")

  to verify that a copy of the same image is pixel-by-pixel the same, and that the checked and unchecked are pixel-by-pixel different.

Notes for reviewers:

As mentioned: I am not a fan of the nested for loops.

Low priority and independent test. So don't rush to review this. It's unlikely to conflict 👍 .