waitForChromeToTerminate.js

import {createServer} from 'http';
function waitForChromeToTerminate() {
    let retry = 5;
    return new Promise((resolve, reject) => {
        const server = createServer();
        server.listen(9222);
        server.once('listening', () => {
            debug('Port is free')
            server.close(() => resolve());
        });
        server.on('error', () => {
            debug('Port is busy retrying')
            setTimeout(() => {
                if (retry) {
                    retry--;
                    server.listen(9222);
                } else {
                  reject('Chrome is still running');
                }
            }, 100);
        });
    })
}