misc: puppeteer script to test a page from devtools

lighthouse-core/scripts/test-dt.js

@@ -0,0 +1,83 @@
+'use strict';
+
+const puppeteer = require('puppeteer');
+
+/**
+ * @param {Record<string, function>} receiver
+ * @param {string} methodName
+ * @param {function} override
+ */
+function addSniffer(receiver, methodName, override) {
+  const original = receiver[methodName];
+  if (typeof original !== 'function') {
+    throw new Error('Cannot find method to override: ' + methodName);
+  }
+
+  receiver[methodName] = function() {
+    let result;
+    try {
+      // eslint-disable-next-line prefer-rest-params
+      result = original.apply(this, arguments);
+    } finally {
+      receiver[methodName] = original;
+    }
+    // In case of exception the override won't be called.
+    try {
+      // eslint-disable-next-line prefer-rest-params
+      Array.prototype.push.call(arguments, result);
+      // eslint-disable-next-line prefer-rest-params
+      override.apply(this, arguments);
+    } catch (e) {
+      throw new Error('Exception in overriden method \'' + methodName + '\': ' + e);
+    }
+    return result;
+  };
+}
+
+const sniff = `
+new Promise(resolve => {
+  (${addSniffer.toString()})(
+    UI.panels.lighthouse.__proto__,
+    '_buildReportUI',
+    (lhr, artifacts) => resolve(JSON.stringify(lhr))
+  );
+});
+`;
+const openPanel = `UI.ViewManager.instance().showView('lighthouse')`;
+const startLH = `UI.panels.lighthouse.contentElement.querySelector('button').click()`;
+
+async function run() {
+  const browser = await puppeteer.launch({
+    executablePath: process.env.CHROME_PATH,
+    devtools: true,
+  });
+  const page = await browser.newPage();
+  await page.goto('https://example.com');
+  const targets = await browser.targets();
+  const dtTarget = targets.filter(t => t.url().includes('devtools'))[1];
+  if (dtTarget) {
+    const session = await dtTarget.createCDPSession();
+    await session.send('Page.enable');
+    await session.send('Runtime.enable');
+    session.once('Page.loadEventFired', async () => {
+      setTimeout(async () => {
+        await session.send('Runtime.evaluate', {expression: openPanel});
+      }, 1000);
+      setTimeout(async () => {
+        await session.send('Runtime.evaluate', {expression: startLH});
+        const remotePromise = await session.send('Runtime.evaluate', {expression: sniff});
+        const remoteLhr = await session.send('Runtime.awaitPromise', {
+          // @ts-expect-error
+          promiseObjectId: remotePromise.result.objectId,
+        }).catch(err => err);
+        // eslint-disable-next-line no-console
+        console.log(remoteLhr.result.value);
+        await page.close();
+        await browser.close();
+      }, 1500);
+      await session.send('Runtime.disable');
+      await session.send('Page.disable');
+    });
+  }
+}
+run();