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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /user-timing/mark-measure-feature-detection.html - WPT Dashboard Interop Dashboard
<!DOCTYPE HTML>
<meta charset=utf-8>
<title>User Timing: L2 vs L3 feature detection</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
test(() => {
// Feature detection for PerformanceMark.
assert_equals(typeof(PerformanceMark.prototype), "object");
// Test for UserTiming L3.
if (PerformanceMark.prototype.hasOwnProperty('detail')) {
assert_equals(typeof(performance.mark("mark")), "object",
"performance.mark should return an object in UserTiming L3.");
}
// Test for UserTiming L2.
else {
assert_equals(typeof(performance.mark("mark")), "undefined",
"performance.mark should be void in UserTiming L2.");
}
}, "Test PerformanceMark existence and feature detection");
test(() => {
// Feature detection for PerformanceMeasure.
assert_equals(typeof(PerformanceMeasure.prototype), "object");
// Test for UserTiming L3.
if (PerformanceMeasure.prototype.hasOwnProperty('detail')) {
assert_equals(typeof(performance.measure("measure")), "object",
"performance.measure should return an object in UserTiming L3.");
}
// Test for UserTiming L2.
else {
assert_equals(typeof(performance.measure("measure")), "undefined",
"performance.measure should be void in UserTiming L2.");
}
}, "Test PerformanceMeasure existence and feature detection");
</script>