page.queryObjects doesn't work as expected

[aslushnikov]

Puppeteer: v1.17.0

Consider the following code snippet:

const puppeteer = require('puppeteer');

async function logRetainedArrays(page) {
  const prototypeHandle = await page.evaluateHandle(() => Array.prototype);
  const instancesHandle = await page.queryObjects(prototypeHandle);
  const retainedArrays = await page.evaluate(instances => instances, instancesHandle);
  console.log(retainedArrays);
  await instancesHandle.dispose();
}

(async() => {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  await page.evaluate(() => {
    window.returnAnArray = () => [42];
    returnAnArray();
  });
  await logRetainedArrays(page);  // [ [ 42 ] ]
  await logRetainedArrays(page);  // [ [ 42 ] ]
  await logRetainedArrays(page);  // [ ]
  await browser.close();
})();

[aslushnikov]

As @ak239 pointed out - looks like this has something to do with Array and Object literals.

[aslushnikov]

For the record: here's the retain chain:

[aslushnikov]

The fix is out for review: https://chromium-review.googlesource.com/c/v8/v8/+/1649473