canvas-filter-origin-clean-shorthands.html

<!doctype html>
<title>CSS shorthand filters never taint the canvas</title>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script>
function assert_not_tainted(performCommands, description) {
  let ctx = document.createElement('canvas').getContext('2d');
  performCommands(ctx);
  assert_not_equals(ctx.getImageData(0, 0, 1, 1), null, description);
}

test(function() {
  assert_not_tainted(ctx => {
    ctx.fillStyle = '#0f0';
    ctx.filter = 'brightness(0.5)';
    ctx.fillRect(5, 5, 10, 10);
  }, 'brightness(0.5)');

  assert_not_tainted(ctx => {
    ctx.filter = 'blur(5px)';
    ctx.fillRect(5, 5, 10, 10);
  }, 'blur(5px)');

  assert_not_tainted(ctx => {
    ctx.filter = 'hue-rotate(45deg) drop-shadow(16px 16px 20px blue)';
    ctx.fillRect(5, 5, 10, 10);
  }, 'hue-rotate(45deg) drop-shadow(16px 16px 20px blue)');
});
</script>

chromium/third_party/blink/web_tests/fast/canvas/canvas-filter-origin-clean-shorthands.html