test_drawDiscardedImage.html (2868B)
1 <!DOCTYPE HTML> 2 <html> 3 <!-- 4 https://bugzilla.mozilla.org/show_bug.cgi?id=731419 5 --> 6 <head> 7 <title>Test for Bug 731419 - Draw an ostensibly discarded image to a canvas</title> 8 <script src="/tests/SimpleTest/SimpleTest.js"></script> 9 <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/> 10 </head> 11 12 <body> 13 14 <!-- 15 Load an image in an iframe, then draw that image to a canvas. Then set the 16 iframe to display:none (after bug 731419, this causes the image's decoded 17 data to be discarded) and draw the image to a canvas again. We should draw 18 the same image data both times. 19 --> 20 21 <script> 22 23 SimpleTest.waitForExplicitFinish(); 24 25 var data1; 26 27 function drawImage() 28 { 29 var canvas = document.getElementById('canvas'); 30 var ctx = canvas.getContext('2d'); 31 var iframeDoc = document.getElementById('iframe').contentDocument; 32 33 ctx.clearRect(0, 0, canvas.height, canvas.width); 34 ctx.drawImage(iframeDoc.getElementById('image'), 0, 0); 35 return canvas.toDataURL(); 36 } 37 38 function iframeLoad() 39 { 40 data1 = drawImage(); 41 document.getElementById('iframe').style.display = 'none'; 42 43 // Spin the event loop a few times to give the image in the display:none 44 // iframe a chance to be discarded. 45 SimpleTest.executeSoon(function() { 46 SimpleTest.executeSoon(function() { 47 SimpleTest.executeSoon(function() { 48 step2(); 49 }); 50 }); 51 }); 52 } 53 54 function step2() 55 { 56 is(drawImage(), data1, "Same image before and after iframe display:none"); 57 SimpleTest.finish(); 58 } 59 60 </script> 61 62 <canvas id='canvas'></canvas> 63 64 <iframe id='iframe' onload='iframeLoad()' srcdoc='<img id="image" 65 src="data:image/png;base64, 66 iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAADRElEQVQ4EQXBTWgcZQCA4ff7ZmZ3 67 NpvNZLObTWpCuoZGIxWJplAKbVUKavUiHrQHaRG1XrV4SNuD4MFcRDwUoR4qEq2gFUlBEWmtppYi 68 acSmMakxtfkx/5tNdmd35/8bn0cAzJ7IXwKGH/q8NDF48vy+7vk/3tzVXDs8nj9cAAiDcD70gwVi 69 vvvr4tsjAAAAAmD2RD4GOL34wge21XHsnHWh9/aUjX1pC4C1UpXrP08zN7vMvvujPx3P/PD+0VH3 70 BoAcTspXAbK9iuGe78+csy70ZnsVvh+xWQ8p1QI8dNK7CiT9CmeO28/4ZsuVX9/IvQwgmzLaU9LS 71 AGh/3KJ5jw6A6ynyL7Xx7UCORiwQGRN0g7C4m4FX9poNV35681ShU6ZbxKDRLJVuZQl9RdSQRB4c 72 OtDGoQNtPGHBuh0SaAa+ZvLjHYt8fwfZrpTl2cFp2ZwVDyQzSgLgVIndGN/tIP/c61y/WWb14gaV 73 asTWioPSDabnfCqVkK7BHKHtPK0n06oFGQHgewJtbw8AujGNkYTNpTJxbYfaygqR0piYkaRkhMya 74 eI2oX9dTQRIFmtrmz7EGpS9vESZjAN7tfo/UL2PouoZwbfxIo9jaoLWlzI7jEPmhLjVEbXs5IPAE 75 jx5M0Z5RZDJwqjCENFN8XBtmOP0FXq1O6NR5snsRtsv4C+voCdHQpcfVtTn/xUKXTrMlyfck6BCC 76 a02fkDZDqirF5JVrRA8ewagu8NbADN6az9btMoTqjnasKDTHjp5PSM3I5DQy7UliZbCz7bCwFDD/ 77 b52h3BCviVHOHv2bvmydyvwOM5MSmch9Ji4/SxMNcaNJTw707zdJmBqeo+G5BuO/V6AzQ5Oo01MI 78 KBaTOOis3rPZrKeqrbn2hwXA10fY7zvicqeZKPQ8YpKxJCgIpEQXisBVhG6MYcQ0pGJp2XWnSpx8 79 52o0ogF8c5/ltMlGIlYHo0qQrq9HxHWFvx3RqCoCFzwn4L+tiIVV5Y5MhWc/mlDnATQAgMkynbMb 80 opoN4z2hUAlPBdpO6FNp+JTtkPVaHE7NYX94K/xqrBT/BvwDIAAAgALQAfT1aWJwtyYea9VEXoAo 81 RfHGYhTfvRfF48BdYB3YAPgfnOuE39kFlREAAAAASUVORK5CYII=">'></iframe> 82 83 </body> 84 </html>