css/cssom-view/getBoundingClientRect-zoom.html

<!DOCTYPE html>
<title>getBoundingClientRect for elements with css zoom</title>
<link rel="author" title="Yotam Hacohen" href="mailto:yotha@chromium.org">
<link rel="author" title="Google" href="http://www.google.com/">
<link rel="help" href="https://drafts.csswg.org/css-viewport/">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
  <head>
    <style>
      div {
        width: 64px;
        height: 64px;
        background-color: blue
      }
      div.x4_zoom {
        zoom: 4.0;
        background-color: blueviolet;
      }
      div.x2_zoom {
        background-color: chartreuse;
        zoom: 2.0;
      }

      div.transform {
        transform: scale(2);
        transform-origin: top left;
      }


    </style>
  </head>
  <body>
    <div id="no_zoom"></div>
    <div class="x4_zoom" id="with_zoom">
    </div>
    <div class="x2_zoom">
      <div class="x4_zoom" id="nested_zoom"></div>
    </div>
    <div id="transform_and_zoom" class="x4_zoom transform"></div>
    <script>
      setup(() => {
        window.noZoom = document.getElementById("no_zoom");
        window.withZoom = document.getElementById("with_zoom");
        window.nestedZoom = document.getElementById("nested_zoom");
        window.transformAndZoom = document.getElementById("transform_and_zoom");
      });
      test(function() {
        assert_true(!!noZoom, "no zoom target exists");
        assert_true(!!withZoom, "zoom target exists");
      });
      test(function() {
        let noZoomRect = noZoom.getBoundingClientRect();
        assert_equals(noZoomRect.left, 8, 'no zoom left');
        assert_equals(noZoomRect.top, 8, 'no zoom top');
        assert_equals(noZoomRect.width, 64, 'no zoom width');
        assert_equals(noZoomRect.height, 64, 'no zoom height');
      });
      test(function() {
        let ZoomRect = withZoom.getBoundingClientRect();
        assert_equals(ZoomRect.left, 8, 'x4 zoom left');
        assert_equals(ZoomRect.top, 8 + 64, 'x4 zoom top');
        assert_equals(ZoomRect.width, 256, 'x4 zoom width');
        assert_equals(ZoomRect.height, 256, 'x4 zoom height');
      });
      test(function() {
        let nestedZoomRect = nestedZoom.getBoundingClientRect();
        assert_equals(nestedZoomRect.left, 8, 'nested zoom left');
        assert_equals(nestedZoomRect.top, 8 + 64 + 256, 'nested zoom top');
        assert_equals(nestedZoomRect.width, 512, 'nested zoom width');
        assert_equals(nestedZoomRect.height, 512, 'nested zoom height');
      });
      test(function() {
        let transformAndZoomRect = transformAndZoom.getBoundingClientRect();
        assert_equals(transformAndZoomRect.left, 8, 'transform and zoom left');
        assert_equals(transformAndZoomRect.top, 8 + 64 + 256 + 128, 'transform and zoom top');
        assert_equals(transformAndZoomRect.width, 512, 'transform and zoom width');
        assert_equals(transformAndZoomRect.height, 512, 'transform and zoom height');
      });
    </script>
  </body>
`