In Ubuntu, executing the command yarn can give you this quizzical error message:

ERROR: There are no scenarios; must have at least one.

My friend, you've got the wrong yarn 😄

✅ Check the version of yarn you have on your system against the released versions https://github.com/yarnpkg/yarn/releases

yarn -v

If the versions differ enormously, then you probably have a yarn package which is part of cmdtest black box testing of Unix command-line tools.

⚠️ Remove the existing yarn (at your own risk) ⚠️

sudo apt-get -remove yarn

And proceed with the instructions from yarnpkg

Simplified instructions:

• Start by adding the yarn proper package repository

curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -

• Then do an Update & Install

sudo apt-get update && sudo apt-get install yarn

• Finally, re-check the version

yarn --version

Happy Hacking 🔨