canvas-update-with-border-object-fit.html

<!doctype html>
<title>Verifies canvas with object-fit and border correctly updates</title>
<link rel="match" href="canvas-update-with-border-object-fit-ref.html">
<html class="reftest-wait">
  <div style="width: 300px; height: 100px; background: black; border: 100px solid blue">
    <canvas id="target" width="1000" height="1000"
        style="object-fit: contain; object-position: center; width: 100%; height: 100%">
    </canvas>
  </div>
</html>
<script>
var ctx = target.getContext("2d");
ctx.fillStyle = "red";
ctx.fillRect(0, 0, target.width, target.height);

var x=0, y=0, step=500;
ctx.fillStyle = "green";
function drawRect() {
  ctx.fillRect(x, y, step, step);
  x += step;
  if (x >= target.width) {
    x = 0;
    y += step;
  }
  if (y >= target.height)
    document.documentElement.classList.remove("reftest-wait");
  else
    requestAnimationFrame(drawRect);
}
drawRect();
</script>

chromium/third_party/blink/web_tests/external/wpt/html/rendering/replaced-elements/embedded-content-rendering-rules/canvas-update-with-border-object-fit.html