LayoutTests/webanimations/transform-animation-with-steps-timing-function-not-accelerated.html

<script src="../resources/testharness.js"></script>
<script src="../resources/testharnessreport.js"></script>
<script src="resources/rendering-frames.js"></script>
<div style="position: absolute; top: 0; left: 0; width: 100px; height: 100px; background-color: black;"></div>
<script>

promise_test(async () => {
    const target = document.querySelector("div");
    const animation = target.animate([
        { transform: "translateY(0px)", easing: "step-start" },
        { transform: "translateY(100px)", easing: "step-start" },
        { transform: "translateY(0px)" }
    ], 60 * 1000);

    await animation.ready;

    // We wait for two frames to ensure an accelerated animation would have been committed.
    await renderingFrames(2);
    assert_equals(internals.acceleratedAnimationsForElement(target).length, 0, "The animation's target has no accelerated animation.");
}, "An animation targeting an accelerated property should not be accelerated if it uses a steps timing function in one of its keyframes.");

</script>