Gmail remove batch messages

Code.gs

let count = 1500;
const batchSize = 100;

async function purgeGmail(query) {
  const items = GmailApp.search("label:github", 0, batchSize);

  console.log(count, items.length);

  await GmailApp.moveThreadsToTrash(items);
  
  count -= batchSize;
  if (count > 0) purgeGmail();
}

devTool_console.js

let count = 32000;
const step = 1500;
const delay = 1000;

const getRunBtn = () => document.querySelector('[aria-label="Run the selected function"]');

function resolveWhenBtnEnables(resolve) {
  function check() {
    if (getRunBtn().disabled) setTimeout(check, delay);
    else resolve();
  }

  setTimeout(check, delay);
}

function waitForRunBtn() {
  return new Promise(resolveWhenBtnEnables);
}

function run() {
  console.log('run', count);
  getRunBtn().click();
  count -= step;
  if (count > 0) waitForRunBtn().then(run);
}

run();

Gmail has limitations for batch operations, so i wrote a little script for it:

1. go to https://script.google.com/
2. create new project
3. paste Code.gs (update search filter)
4. open devTool console
5. paste devTool_console.js (update variable count)
6. press Enter