chromium/third_party/blink/web_tests/wpt_internal/geolocation-api/timestamp.https.html

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
<html>
<head>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/testharness-adapter.js"></script>
</head>
<body>
<script type="module">
import {GeolocationMock} from './resources/geolocation-mock.js';

description("Tests that Geoposition timestamps are well-formed (non-zero and in the same units as Date.getTime).");

const mockLatitude = 51.478;
const mockLongitude = -0.166;
const mockAccuracy = 100.0;

const now = new Date().getTime();
assert_not_equals(now, 0);
let t = null;
let then = null;

const mock = new GeolocationMock();
mock.setGeolocationPermission(true);
mock.setGeolocationPosition(mockLatitude, mockLongitude, mockAccuracy);

function checkPosition(p) {
    t = p.timestamp;
    const d = new Date();
    then = d.getTime();
    assert_not_equals(t, 0);
    assert_not_equals(then, 0);
    assert_less_than_equal(now - 1, t);  // Avoid rounding errors
    assert_less_than_equal(t, then + 1);  // Avoid rounding errors
    finishJSTest();
}

navigator.geolocation.getCurrentPosition(checkPosition);
</script>
</body>
</html>