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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /hr-time/basic.any.html - WPT Dashboard Interop Dashboard
- /hr-time/basic.any.worker.html - WPT Dashboard Interop Dashboard
test(function() {
assert_true((self.performance !== undefined), "self.performance exists");
assert_equals(typeof self.performance, "object", "self.performance is an object");
assert_equals((typeof self.performance.now), "function", "self.performance.now() is a function");
assert_equals(typeof self.performance.now(), "number", "self.performance.now() returns a number");
}, "self.performance.now() is a function that returns a number");
test(function() {
assert_true(self.performance.now() > 0);
}, "self.performance.now() returns a positive number");
test(function() {
var now1 = self.performance.now();
var now2 = self.performance.now();
assert_true((now2-now1) >= 0);
}, "self.performance.now() difference is not negative");
async_test(function() {
// Check whether the performance.now() method is close to Date() within 30ms (due to inaccuracies)
var initial_hrt = self.performance.now();
var initial_date = Date.now();
this.step_timeout(function() {
var final_hrt = self.performance.now();
var final_date = Date.now();
assert_approx_equals(final_hrt - initial_hrt, final_date - initial_date, 30, 'High resolution time value increased by approximately the same amount as time from date object');
this.done();
}, 2000);
}, 'High resolution time has approximately the right relative magnitude');
test(function() {
var didHandle = false;
self.performance.addEventListener("testEvent", function() {
didHandle = true;
}, { once: true} );
self.performance.dispatchEvent(new Event("testEvent"));
assert_true(didHandle, "Performance extends EventTarget, so event dispatching should work.");
}, "Performance interface extends EventTarget.");