svoid assertSameSize(BufferedImage a, BufferedImage b) {
  assertEquals(
    pair(a.getWidth(), a.getHeight()),
    pair(b.getWidth(), b.getHeight()));
}

svoid assertSameSize(WidthAndHeight a, WidthAndHeight b) {
  assertEquals(
    pair(a.getWidth(), a.getHeight()),
    pair(b.getWidth(), b.getHeight()));
}