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<!DOCTYPE html>
<head>
<title>Performance Paint Timing Test: FCP due to canvas</title>
</head>
<body>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<canvas id="canvas" width="200" height="200" ></canvas>
<script>
setup({"hide_test_state": true});
async_test(function (t) {
assert_implements(window.PerformancePaintTiming, "Paint Timing isn't supported.");
const canvas = document.getElementById("canvas");
const context = canvas.getContext("2d");
context.beginPath();
context.moveTo(0,0);
context.lineTo(300,150);
context.stroke();
function testPaintEntries() {
const bufferedEntries = performance.getEntriesByType('paint');
if (bufferedEntries.length < 2) {
t.step_timeout(function() {
testPaintEntries();
}, 20);
return;
}
t.step(function() {
assert_equals(bufferedEntries.length, 2, "There should be two paint timing instances.");
assert_equals(bufferedEntries[0].entryType, "paint");
assert_equals(bufferedEntries[0].name, "first-paint");
assert_equals(bufferedEntries[1].entryType, "paint");
assert_equals(bufferedEntries[1].name, "first-contentful-paint");
t.done();
});
};
t.step(function() {
testPaintEntries();
});
}, "First contentful paint fires due to canvas render.");
</script>
</body>
</html>
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