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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /css/css-variables/variable-animation-from-to.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<html>
<head>
<title>CSS Variables - Animation - From and To Values</title>
<meta rel="author" title="Kevin Babbitt">
<meta rel="author" title="Greg Whitworth">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
@keyframes valueanim
{
from { --value: blue; }
to { --value: green; }
}
/* Start the animation in the paused state and fill at both ends so we can inspect values from both keyframes. */
#target
{
animation-name: valueanim;
animation-duration: 1s;
animation-play-state: paused;
animation-fill-mode: both;
--value: red;
color: var(--value);
}
</style>
</head>
<body>
<div id="target">This text should animate from blue to green over a period of 1 second.</div>
<script type="text/javascript">
"use strict";
// Force an initial layout pass
document.documentElement.offsetHeight;
test(function() {
assert_equals(window.getComputedStyle(document.getElementById("target")).getPropertyValue("--value").trim(), "blue", "--value is blue before animation runs");
}, "Verify CSS variable value before animation");
test(function() {
assert_equals(window.getComputedStyle(document.getElementById("target")).getPropertyValue("color").trim(), "rgb(0, 0, 255)", "color is blue before animation runs");
}, "Verify substituted color value before animation");
var afterAnimationVariableTest = async_test("Verify CSS variable value after animation");
document.getElementById("target").addEventListener("animationend", afterAnimationVariableTest.step_func_done(function() {
assert_equals(window.getComputedStyle(document.getElementById("target")).getPropertyValue("--value").trim(), "green", "--value is green after animation runs")
}));
var afterAnimationColorTest = async_test("Verify substituted color value after animation");
document.getElementById("target").addEventListener("animationend", afterAnimationColorTest.step_func_done(function() {
assert_equals(window.getComputedStyle(document.getElementById("target")).getPropertyValue("color").trim(), "rgb(0, 128, 0)", "color is green after animation runs")
}));
// Trigger animation
document.getElementById("target").style.animationPlayState = "running";
</script>
</body>
</html>