Source code
Revision control
Copy as Markdown
Other Tools
/* eslint-disable mozilla/no-comparison-or-assignment-inside-ok */
function ok(a, msg) {
postMessage({ type: "status", status: !!a, msg });
}
function is(a, b, msg) {
ok(a === b, msg);
}
function finish() {
postMessage({ type: "finish" });
}
let isRounded = (x, expectedPrecision) => {
let rounded = Math.floor(x / expectedPrecision) * expectedPrecision;
// First we do the perfectly normal check that should work just fine
if (rounded === x || x === 0) {
return true;
}
// When we're diving by non-whole numbers, we may not get perfect
// multiplication/division because of floating points.
// When dealing with ms since epoch, a double's precision is on the order
// of 1/5 of a microsecond, so we use a value a little higher than that as
// our epsilon.
// To be clear, this error is introduced in our re-calculation of 'rounded'
// above in JavaScript.
if (Math.abs(rounded - x + expectedPrecision) < 0.0005) {
return true;
} else if (Math.abs(rounded - x) < 0.0005) {
return true;
}
// Then we handle the case where you're sub-millisecond and the timer is not
// We check that the timer is not sub-millisecond by assuming it is not if it
// returns an even number of milliseconds
if (expectedPrecision < 1 && Math.round(x) == x) {
if (Math.round(rounded) == x) {
return true;
}
}
ok(
false,
"Looming Test Failure, Additional Debugging Info: Expected Precision: " +
expectedPrecision +
" Measured Value: " +
x +
" Rounded Vaue: " +
rounded +
" Fuzzy1: " +
Math.abs(rounded - x + expectedPrecision) +
" Fuzzy 2: " +
Math.abs(rounded - x)
);
return false;
};
function runTimerTests(expectedPrecision) {
ok(
isRounded(performance.timeOrigin, expectedPrecision),
`In a worker, for reduceTimerPrecision, performance.timeOrigin is not correctly rounded: ` +
performance.timeOrigin
);
// Try to add some entries.
performance.mark("Test");
performance.mark("Test-End");
performance.measure("Test-Measure", "Test", "Test-End");
// Check the entries in performance.getEntries/getEntriesByType/getEntriesByName.
is(
performance.getEntries().length,
3,
"In a worker, for reduceTimerPrecision: Incorrect number of entries for performance.getEntries() for workers: " +
performance.getEntries().length
);
for (var i = 0; i < 3; i++) {
let startTime = performance.getEntries()[i].startTime;
let duration = performance.getEntries()[i].duration;
ok(
isRounded(startTime, expectedPrecision),
"In a worker, for reduceTimerPrecision(" +
expectedPrecision +
"), performance.getEntries(" +
i.toString() +
").startTime is not rounded: " +
startTime.toString()
);
ok(
isRounded(duration, expectedPrecision),
"In a worker, for reduceTimerPrecision(" +
expectedPrecision +
"), performance.getEntries(" +
i.toString() +
").duration is not rounded: " +
duration.toString()
);
}
is(
performance.getEntriesByType("mark").length,
2,
"In a worker, for reduceTimerPrecision: Incorrect number of entries for performance.getEntriesByType() for workers: " +
performance.getEntriesByType("resource").length
);
is(
performance.getEntriesByName("Test", "mark").length,
1,
"In a worker, for reduceTimerPrecision: Incorrect number of entries for performance.getEntriesByName() for workers: " +
performance.getEntriesByName("Test", "mark").length
);
finish();
}
self.onmessage = function (e) {
if (e.data.type === "runTimerTests") {
runTimerTests(e.data.precision);
} else {
ok(false, "Unknown message type");
}
};