I don’t know about you, but I quite like the Jest convention of putting tests in __tests__ directories. It keeps the tests local to the modules they’re testing, and visible in the src directory, rather than hidden away in test. I know, it’s the little things.

Anyway, here’s how to achieve that with Mocha, my test runner of choice. Just stick the following in your package.json scripts:

"mocha": "find ./src -wholename \"./*__tests__/*\" | xargs mocha -R spec"

Inspired by this Gist.

EDIT - Alternatively, this is much simpler and seems to work:

"mocha": "mocha 'src/**/__tests__/*' -R spec"