resource-timing/buffer-full-set-to-current-buffer.html

<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>This test validates that setResourceTimingBufferFull behaves appropriately when set to the current buffer level.</title>
<link rel="author" title="Google" href="http://www.google.com/" />
<link rel="help" href="https://www.w3.org/TR/resource-timing-2/#dom-performance-onresourcetimingbufferfull">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/resource-loaders.js"></script>
<script src="resources/buffer-full-utilities.js"></script>
</head>
<body>
<script>
promise_test(async () => {
    let result = '';
    performance.addEventListener('resourcetimingbufferfull', () => {
        result += 'Event Fired with '  +
            performance.getEntriesByType('resource').length + ' entries.';
        performance.clearResourceTimings();
    });
    result += 'Before adding entries. ';
    await fillUpTheBufferWithTwoResources();
    result += 'After adding entries. ';
    load.script(scriptResources[2]);
    await bufferFullFirePromise;
    assert_equals(result, 'Before adding entries. After adding entries. Event Fired with 2 entries.');
    const entries = performance.getEntriesByType('resource');
    assert_equals(entries.length, 1,
        'Number of entries in resource timing buffer is unexpected');
    assert_true(entries[0].name.includes(scriptResources[2]),
        'The entry must correspond to the last resource loaded.')
}, "Test that adding entries and firing the buffer full event happen in the right order.");
</script>