~/Documents/gerrit/mediawiki/vagrant$ vagrant ssh
...

vagrant@vagrant:/vagrant/mediawiki$ node -v
v6.17.1

vagrant@vagrant:/vagrant/mediawiki$ npm -v
2.15.12

vagrant@vagrant:~$ cd /vagrant/mediawiki/

vagrant@vagrant:/vagrant/mediawiki$ rm -rf node_modules/

vagrant@vagrant:/vagrant/mediawiki$ npm install
...

vagrant@vagrant:/vagrant/mediawiki$ npm run selenium

> @ selenium /vagrant/mediawiki
> wdio ./tests/selenium/wdio.conf.js

/vagrant/mediawiki/node_modules/@wdio/cli/build/launcher.js:62
  async run() {
        ^^^

SyntaxError: Unexpected identifier
    at createScript (vm.js:56:10)
    at Object.runInThisContext (vm.js:97:10)
    at Module._compile (module.js:549:28)
    at Object.Module._extensions..js (module.js:586:10)
    at Module.load (module.js:494:32)
    at tryModuleLoad (module.js:453:12)
    at Function.Module._load (module.js:445:3)
    at Module.require (module.js:504:17)
    at require (internal/module.js:20:19)
    at Object.<anonymous> (/vagrant/mediawiki/node_modules/@wdio/cli/build/index.js:14:40)

npm ERR! Linux 4.9.0-9-amd64
npm ERR! argv "/usr/bin/node" "/usr/bin/npm" "run" "selenium"
npm ERR! node v6.17.1
npm ERR! npm  v2.15.12
npm ERR! code ELIFECYCLE
npm ERR! @ selenium: `wdio ./tests/selenium/wdio.conf.js`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the @ selenium script 'wdio ./tests/selenium/wdio.conf.js'.
npm ERR! This is most likely a problem with the  package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     wdio ./tests/selenium/wdio.conf.js
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs 
npm ERR! Or if that isn't available, you can get their info via:
npm ERR! 
npm ERR!     npm owner ls 
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     /vagrant/mediawiki/npm-debug.log