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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /performance-timeline/po-observe.html - WPT Dashboard Interop Dashboard
<!DOCTYPE HTML>
<meta charset=utf-8>
<title>PerformanceObservers: PerformanceObserverInit.buffered</title>
<meta name="timeout" content="long">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="performanceobservers.js"></script>
<h1>PerformanceObservers: PerformanceObserverInit.buffered</h1>
<p>
PerformanceObserverInit.buffered should retrieve previously buffered entries
</p>
<div id="log"></div>
<script>
async_test(function (t) {
function initTest() {
new PerformanceObserver(function (entryList, observer) {
entryList.getEntries().forEach(function(entry) {
if (shouldExclude(entry)) {
return;
}
observedEntries.push(entry);
if (observedEntries.length === entryTypes.length) {
observer.disconnect();
runTest();
}
});
}).observe({entryTypes});
// creates a `resource` entry
var img = document.createElement("img");
img.src = "./resources/square.png";
document.body.appendChild(img);
performance.mark("markName"); // creates a `mark` entry
performance.measure("measureName"); // creates a `measure` entry
}
function shouldExclude(entry) {
// exclude all `resource` entries that aren't for "square.png"
return entry.entryType === "resource" &&
entry.name.indexOf("square.png") === -1;
}
function runTest() {
// this PerformanceObserver is a nop because we've already been notified about all of our `entryTypes`
var po_nop = new PerformanceObserver(function (entryList, observer) {
if (entryList.getEntries().find(function(entry) {
return !shouldExclude(entry);
})) {
assert_unreached("this PerformanceObserver callback should never be called");
}
});
po_nop.observe({
entryTypes,
});
// this PerformanceObserver should be notified about the previously
// buffered mark entry only
const bufferedEntries = [];
new PerformanceObserver(function (entryList, observer) {
entryList.getEntries().forEach(function(entry) {
if (shouldExclude(entry)) {
return;
}
bufferedEntries.push(entry);
if (bufferedEntries.length === 1) {
observer.disconnect();
po_nop.disconnect();
for (i = 0; i < bufferedEntries.length; i++) {
assert_equals(bufferedEntries[i].entryType, "mark")
}
t.done();
}
});
}).observe({
type: "mark",
buffered: true
});
}
const entryTypes = ["navigation", "resource", "mark", "measure"];
const observedEntries = [];
initTest();
}, "PerformanceObserverInit.buffered should retrieve previously buffered entries");
</script>