If useAuth is a singleton, how to unit test the component that uses it properly?

[chenxeed]

Hi,

my question might be specific to the general way of testing Context API in React that acts as a singleton.

I believe it's a great help to showcase how is this useAuth library is going to be tested since it's (seems like) a singleton. Thanks!

[Swizec]

This is a great question @chenxeed. useAuth might look like a singleton, but it sort of isn't.

Every time you render an AuthProvider, we create everything from scratch internally. Auth0 client is instantiated, state object is set up, etc. From that point onward, all children components share that same state and Auth0 client via context.

So if you wanted to test this, my recommendation is to render a new AuthProvider for every test. That ensures you get a clean test every time.

If you want to test that multiple components correctly share that state, then I'm not really sure. I suspect you're then going into the territory of testing React itself.

That said, I should probably add some proper tests to this library :D