public function testChecksum() { // checksum of empty image $sum = '40cd750bba9870f18aada2478b24840a'; $img = new ImageCache(); $this->assertEquals($sum, $img->checksum()); // checksum of test image resized to 300x200 $sum = '792dcbdcefdd977a099b6fdd06c8ab57'; $img = new ImageCache(); $img->open('foo/bar.jpg'); $img->resize(300, 200); $this->assertEquals($sum, $img->checksum()); }