I have a simple question for people who use react-native and Expo.
I am using the following technologies

• Styled-components
• react-native-paper
• Context API (for Authentication)

I am new to testing in Jest/Testing-library but I want to know how to start testing my app.

I have specific question which is :
How to test the functions that reside inside Context Provider?

I have functions such as RegisterValidation (checks username and password patterns) Register

I React states such as isLoading and error

I have been trying for 2 days but did not find a real solution.

What I did Until Now:

I installed jest-expo and did some configurations
I tried to test the functions directly but got an error due to useState

I tried to test through a child component but an error like this

   TypeError: Cannot read properties of undefined (reading 'onRegister')
      31 |   });
    > 32 |   const { onRegister, isLoading, error } = useContext(AuthContext);

I have been dealing with some error with styled-components as well

I do not know where to start and what to do now.