chromium/third_party/blink/web_tests/external/wpt/fullscreen/rendering/ua-style-iframe.html

<!DOCTYPE html>
<title>User-agent levels style sheet defaults for iframe</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../trusted-click.js"></script>
<style>
  iframe {
    border: 1px solid blue;
    padding: 1px;
    /* transform is also tested because of https://crbug.com/662393 */
    transform: scale(0.5);
  }
</style>
<div id="log"></div>
<div id="ancestor"><iframe></iframe></div>
<script>
  function assert_dir_properties(style, propBase, value, state) {
    for (let dir of ["Top", "Right", "Bottom", "Left"]) {
      let prop = propBase.replace("{}", dir);
      assert_equals(style[prop], value, `${state} ${prop} style`);
    }
  }

  promise_test(async (t) => {
    t.add_cleanup(() => {
      if (document.fullscreenElement) {
        return document.exitFullscreen();
      }
    });
    const ancestor = document.getElementById("ancestor");
    const iframe = ancestor.firstChild;

    const initialStyle = getComputedStyle(iframe);
    assert_dir_properties(initialStyle, "border{}Width", "1px", "initial");
    assert_dir_properties(initialStyle, "border{}Style", "solid", "initial");
    assert_dir_properties(
      initialStyle,
      "border{}Color",
      "rgb(0, 0, 255)",
      "initial"
    );
    assert_dir_properties(initialStyle, "padding{}", "1px", "initial");
    assert_equals(
      initialStyle.transform,
      "matrix(0.5, 0, 0, 0.5, 0, 0)",
      "initial transform style"
    );

    await trusted_request(iframe);
    await fullScreenChange();

    const fullscreenStyle = getComputedStyle(iframe);
    assert_dir_properties(
      fullscreenStyle,
      "border{}Width",
      "0px",
      "fullscreen"
    );
    assert_dir_properties(
      fullscreenStyle,
      "border{}Style",
      "none",
      "fullscreen"
    );
    assert_dir_properties(
      fullscreenStyle,
      "border{}Color",
      "rgb(0, 0, 0)",
      "fullscreen"
    );
    assert_dir_properties(fullscreenStyle, "padding{}", "0px", "fullscreen");
    assert_equals(
      fullscreenStyle.transform,
      "none",
      "fullscreen transform style"
    );
  });
</script>