runtime/world.js
function getDriverInstance() {

    var driver;

    switch (browserName || '') {

        case 'firefox': {
            driver = new FireFoxDriver();
        }
            break;

        case 'phantomjs': {
            driver = new PhantomJSDriver();
        }
            break;

        case 'electron': {
            driver = new ElectronDriver();
        }
            break;

        case 'chrome': {
            driver = new ChromeDriver();
        }
            break;

        // try to load from file
        default: {
            var driverFileName = path.resolve(process.cwd(), browserName);

            if (!fs.isFileSync(driverFileName)) {
                throw new Error('Could not find driver file: ' + driverFileName);
            }

            driver = require(driverFileName)();
        }
    }

    return driver;
}
function getDriverInstance() {

    var driver;

    switch (browserName || '') {

        case 'firefox': {
            driver = new FireFoxDriver();
        }
            break;

        case 'phantomjs': {
            driver = new PhantomJSDriver();
        }
            break;

        case 'electron': {
            driver = new ElectronDriver();
        }
            break;

        case 'chrome': {
            driver = new ChromeDriver();
        }
            break;

        // try to load from file
        default: {
            var driverFileName = path.resolve(process.cwd(), browserName);

            if (!fs.isFileSync(driverFileName)) {
                throw new Error('Could not find driver file: ' + driverFileName);
            }

            driver = require(driverFileName)();
        }
    }

    return driver;
}
function getDriverInstance ( ) { var driver ; switch ( browserName || '' ) { case 'firefox' : { driver = new FireFoxDriver ( ) ; } break ; case 'phantomjs' : { driver = new PhantomJSDriver ( ) ; } break ; case 'electron' : { driver = new ElectronDriver ( ) ; } break ; case 'chrome' : { driver = new ChromeDriver ( ) ; } break ; // try to load from file default : { var driverFileName = path . resolve ( process . cwd ( ) , browserName ) ; if ( ! fs . isFileSync ( driverFileName ) ) { throw new Error ( 'Could not find driver file: ' + driverFileName ) ; } driver = require ( driverFileName ) ( ) ; } } return driver ; }
create the selenium browser based on global var set in index.js
@returns {ThenableWebDriver} selenium web driver
create the selenium browser based on global var set in index . js