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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* global require, module */
const { logTest } = require("./utils/profiling");
module.exports = logTest(
"speculation rules prefetch",
async function (context, commands) {
const serverUrl = context.options.browsertime.server_url;
if (!serverUrl) {
throw new Error(
"speculation-rules-prefetch: missing --browsertime.server_url; " +
"is support_class=speculation_rules.py wired in?"
);
}
const buttonId = context.options.browsertime.button_id || "btn-a";
// Covers the ~200 ms moderate-eagerness trigger + 500 ms backend stall.
const dwellMs = Number(context.options.browsertime.dwell_ms ?? 1000);
context.log.info(
`speculation-rules-prefetch: button=${buttonId}, dwell_ms=${dwellMs}`
);
await commands.navigate(`${serverUrl}/landing.html`);
await commands.wait.byTime(250);
await commands.measure.start();
await commands.mouse.moveTo.bySelector(`#${buttonId}`);
await commands.wait.byTime(dwellMs);
await commands.mouse.singleClick.bySelector(`#${buttonId}`);
await commands.wait.byTime(2500);
await commands.measure.stop();
const navInfo = await commands.js.run(`
const nav = performance.getEntriesByType('navigation')[0];
return nav ? {
deliveryType: nav.deliveryType || "",
type: nav.type,
duration: nav.duration,
responseStart: nav.responseStart,
domContentLoadedEventEnd: nav.domContentLoadedEventEnd,
loadEventEnd: nav.loadEventEnd,
href: location.href,
} : null;
`);
context.log.info(
`speculation-rules-prefetch: navigation entry = ${JSON.stringify(navInfo)}`
);
if (!navInfo) {
throw new Error(
"speculation-rules-prefetch: no navigation entry found on target page"
);
}
await commands.measure.addObject({
custom_data: {
delivery_type: navInfo.deliveryType,
navigation_duration: navInfo.duration,
response_start: navInfo.responseStart,
},
});
return true;
}
);