I'm wondering about the rationale of the last two 'testInvalidCropRegion' tests. In the second to last test, region.height is varied even though it is not relevant since the region is invalid based on the region 'left + width' being greater than image width. Similarly, in the last test, region.width is varied but is not relevant because the region 'left + width' is always valid regardless of the varying values of the region width while the test passes because region 'top + height' is always invalid based on the image height.