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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/rendering/replaced-elements/attributes-for-embedded-content-and-images/video-aspect-ratio.html - WPT Dashboard Interop Dashboard
<!doctype html>
<title>Video width and height attributes are used to infer aspect-ratio</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/common/media.js"></script>
<script src="resources/aspect-ratio.js"></script>
<style>
video {
width: 100%;
max-width: 100px;
height: auto;
}
</style>
<body>
<video width="250" height="100" id="contained" style="contain: size;"></video>
<script>
function assert_ratio(element, expected, description) {
let epsilon = 0.001;
assert_approx_equals(
parseFloat(getComputedStyle(element).width) / parseFloat(getComputedStyle(element).height),
expected,
epsilon,
description,
);
}
function test_computed_style(width, height, expected) {
test_computed_style_aspect_ratio("video", {width: width, height: height}, expected);
}
promise_test(async function() {
let video = document.getElementById("contained");
video.src = getVideoURI('/media/2x2-green');
assert_ratio(video, 2.5);
}, "Aspect ratio for video with contain:size");
// Create and append a new video and immediately check the ratio.
// This is not racy because the spec requires the user agent to queue a task:
promise_test(async function() {
let video = document.createElement("video");
video.setAttribute("width", "250");
video.setAttribute("height", "100");
video.src = getVideoURI('/media/2x2-green');
document.body.appendChild(video);
assert_ratio(video, 2.5, "aspect ratio before load");
await new Promise(r => video.addEventListener("loadeddata", r, { once: true }));
// When loaded this video is square.
assert_ratio(video, 1, "aspect ratio after load");
}, "Aspect ratio for regular video");
// Same but with auto width.
promise_test(async function() {
let video = document.createElement("video");
video.setAttribute("width", "250");
video.setAttribute("height", "100");
video.style.width = "auto";
video.src = getVideoURI('/media/2x2-green');
document.body.appendChild(video);
assert_ratio(video, 2.5, "aspect ratio before load");
await new Promise(r => video.addEventListener("loadeddata", r, { once: true }));
assert_ratio(video, 1, "aspect ratio after load");
}, "Aspect ratio for regular video with width:auto");
// Same but with auto aspect-ratio.
promise_test(async function() {
let video = document.createElement("video");
video.setAttribute("width", "250");
video.setAttribute("height", "100");
video.style.aspectRatio = "auto";
video.src = getVideoURI('/media/2x2-green');
document.body.appendChild(video);
// The aspect ratio is 2 because the default size is 300x150.
assert_ratio(video, 2, "aspect ratio before load");
await new Promise(r => video.addEventListener("loadeddata", r, { once: true }));
// But now we can use the natural ratio from the video source.
assert_ratio(video, 1, "aspect ratio after load");
}, "Aspect ratio for regular video with aspect-ratio:auto");
test_computed_style("10", "20", "auto 10 / 20");
test_computed_style("0.5", "1.5", "auto 0.5 / 1.5");
test_computed_style("0", "1", "auto 0 / 1");
test_computed_style("1", "0", "auto 1 / 0");
test_computed_style("0", "0", "auto 0 / 0");
test_computed_style(null, null, "auto");
test_computed_style("10", null, "auto");
test_computed_style(null, "20", "auto");
test_computed_style("xx", "20", "auto");
test_computed_style("10%", "20", "auto");
</script>