mozilla-release/testing/web-platform/tests/resource-timing/resource_timing_same_origin_redirect.html

<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8" />
<title>This test validates the values of the redirectStart/End in resource timing for a same-origin resource redirect.</title>
<link rel="author" title="Intel" href="http://www.intel.com/" />
<link rel="help" href="http://www.w3.org/TR/resource-timing/#performanceresourcetiming"/>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/webperftestharness.js"></script>
<script src="resources/webperftestharnessextension.js"></script>

<script>
    setup({explicit_done: true});
    function onload_test() {
        const context = new PerformanceContext(performance);
        const entry = context.getEntriesByName(document.getElementById('frameContext').src, 'resource')[0];

        test_greater_than(entry.redirectStart, 0, 'redirectStart should be greater than 0 in same-origin redirect.');
        test_equals(entry.redirectStart, entry.startTime, 'redirectStart should be equal to startTime in same-origin redirect.');
        test_noless_than(entry.redirectEnd, entry.redirectStart, 'redirectEnd should be no less than redirectStart in same-origin redirect.');
        test_noless_than(entry.fetchStart, entry.redirectEnd, 'fetchStart should be no less than redirectEnd in same-origin redirect.');
        done();
    }
</script>

</head>
<body>
<iframe id="frameContext" src="" style="width: 250px; height: 250px;"></iframe>
<script>
    let destUrl = '/common/redirect.py';
    destUrl += '?location=/resource-timing/resources/blank_page_green.htm';

    const frameContext = document.getElementById('frameContext');
    frameContext.onload = onload_test;
    frameContext.src = destUrl;
</script>
</body>
</html>