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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /intersection-observer/initial-observation-with-threshold.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<meta name="viewport" content="width=device-width,initial-scale=1">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="./resources/intersection-observer-test-utils.js"></script>
<style>
pre, #log {
position: absolute;
top: 0;
left: 200px;
}
.spacer {
height: calc(100vh + 100px);
}
#root {
display: inline-block;
overflow-y: scroll;
height: 240px;
border: 3px solid black;
}
#target {
width: 100px;
height: 100px;
margin: 200px 0 0 0;
background-color: green;
}
</style>
<div id="root">
<div id="target"></div>
</div>
<script>
var entries = [];
var root, target;
runTestCycle(function() {
target = document.getElementById("target");
assert_true(!!target, "target exists");
root = document.getElementById("root");
assert_true(!!root, "root exists");
var observer = new IntersectionObserver(function(changes) {
entries = entries.concat(changes)
}, { root: root, threshold: [0.5] });
observer.observe(target);
entries = entries.concat(observer.takeRecords());
assert_equals(entries.length, 0, "No initial notifications.");
runTestCycle(step0, "First rAF");
}, "First observation with a threshold.");
function step0() {
root.scrollTop = 20;
runTestCycle(step1, "root.scrollTop = 20");
checkLastEntry(entries, 0, [ 11, 111, 211, 311, 11, 111, 211, 251, 11, 111, 11, 251, false]);
}
function step1() {
checkLastEntry(entries, 1, [ 11, 111, 191, 291, 11, 111, 191, 251, 11, 111, 11, 251, true]);
}
</script>