Mocha not found!

Hello friends
I’m trying to develop a restful api with nodejs and I want to integrate the application that I went live with heroku with travis, but even though I did everything, mocha: not found
The command “npm run test” exited with 127 error. I would be very grateful if you could help me with my first use of Travis.

Try adding:

before_script:
  - npm run bootstrap

To your .travis.yml.