"use strict"; /** * Tests the FX_TAB_SWITCH_SPINNER_VISIBLE_MS and * FX_TAB_SWITCH_SPINNER_VISIBLE_LONG_MS telemetry probes */ let gMinHangTime = 500; // ms let gMaxHangTime = 5 * 1000; // ms /** * Make a data URI for a generic webpage with a script that hangs for a given * amount of time. * @param {?Number} aHangMs Number of milliseconds that the hang should last. * Defaults to 0. * @return {String} The data URI generated. */ function makeDataURI(aHangMs = 0) { return `data:text/html, Tab Spinner Test

Tab Spinner Test

`; } /** * Returns the sum of all values in an array. * @param {Array} aArray An array of integers * @return {Number} The sum of the integers in the array */ function sum(aArray) { return aArray.reduce(function(previousValue, currentValue) { return previousValue + currentValue; }); } /** * A generator intended to be run as a Task. It tests one of the tab spinner * telemetry probes. * @param {String} aProbe The probe to test. Should be one of: * - FX_TAB_SWITCH_SPINNER_VISIBLE_MS * - FX_TAB_SWITCH_SPINNER_VISIBLE_LONG_MS */ function* testProbe(aProbe) { info(`Testing probe: ${aProbe}`); let histogram = Services.telemetry.getHistogramById(aProbe); let buckets = histogram.snapshot().ranges.filter(function(value) { return (value > gMinHangTime && value < gMaxHangTime); }); let delayTime = buckets[0]; // Pick a bucket arbitrarily // The tab spinner does not show up instantly. We need to hang for a little // bit of extra time to account for the tab spinner delay. delayTime += gBrowser.selectedTab.linkedBrowser.getTabBrowser()._getSwitcher().TAB_SWITCH_TIMEOUT; let dataURI1 = makeDataURI(delayTime); let dataURI2 = makeDataURI(); let tab1 = yield BrowserTestUtils.openNewForegroundTab(gBrowser, dataURI1); histogram.clear(); // Queue a hang in the content process when the // event loop breathes next. ContentTask.spawn(tab1.linkedBrowser, null, function*() { content.wrappedJSObject.hang(); }); let tab2 = yield BrowserTestUtils.openNewForegroundTab(gBrowser, dataURI2); let snapshot = histogram.snapshot(); yield BrowserTestUtils.removeTab(tab2); yield BrowserTestUtils.removeTab(tab1); ok(sum(snapshot.counts) > 0, `Spinner probe should now have a value in some bucket`); } add_task(function* setup() { yield SpecialPowers.pushPrefEnv({ set: [["dom.ipc.processCount", 1]] }); }); add_task(testProbe.bind(null, "FX_TAB_SWITCH_SPINNER_VISIBLE_MS")); add_task(testProbe.bind(null, "FX_TAB_SWITCH_SPINNER_VISIBLE_LONG_MS"));