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/*
* tresize-test - A purer form of paint measurement than tpaint. This
* test opens a single window positioned at 10,10 and sized to 425,425,
* then resizes the window outward |max| times measuring the amount of
* time it takes to repaint each resize. Calls the provided callback
* with an array of resize times in milliseconds.
*/
async function runTest(callback, locationSearch) {
const INCREMENT = 3;
const MAX = 200;
// Measure the time it take for the provided action to trigger a
// MozAfterPaint event. This function ensures that the event being
// measured is really a result of the given action.
function measurePaintTime(action, marker) {
return new Promise(resolve => {
let startTime;
let lastTransaction = window.windowUtils.lastTransactionId;
function painted(event) {
if (event.transactionId <= lastTransaction) {
return;
}
if (marker) {
Profiler.subtestEnd(marker);
}
window.removeEventListener("MozAfterPaint", painted, true);
let time = event.paintTimeStamp - startTime;
resolve(time);
}
window.addEventListener("MozAfterPaint", painted, true);
if (marker) {
Profiler.subtestStart(marker);
}
startTime = window.performance.now();
action();
});
}
// Position the intial window and set up profiling...
let windowSize = 425;
await measurePaintTime(() => {
window.moveTo(10, 10);
window.resizeTo(windowSize, windowSize);
});
Profiler.initFromURLQueryParams(locationSearch);
Profiler.beginTest("tresize");
let times = [];
for (let i = 0; i < MAX; i++) {
const marker = `resize ${i}`;
windowSize += INCREMENT;
let time = await measurePaintTime(() => {
window.resizeTo(windowSize, windowSize);
}, marker);
times.push(time);
await new Promise(resolve => setTimeout(resolve, 20));
}
let total = times.reduce((a, b) => a + b);
let average = total / times.length;
callback({ average });
}