The initial round was a telephonic interview. Later, I had one Webex interview where we needed to display our PAN and ID proofs before the interview. Following that, there was a communication round, which was an online test.

JavaScript objects

Classes and inheritance in JS

Predefined functions in JS

Event loop

Mechanics of JS

What is async?

Arrow functions vs. normal functions

ES6 features

Multithreading in JS

What is a constructor and default value?

What are classes in React? Function and class-based components in React

Component lifecycles

Deprecated methods

Best method to call an API

Difference between lifecycles

Props and state

HOC (Higher-Order Components)

How to implement and where to implement HOCs

Redux, Context API

Why Redux?

What are mapDispatchToProps and mapStateToProps? What parameters do they accept in connect?

React Router - version?

Is it possible to transfer data from one component without state and props? (React Router)

How will you implement authentication in ReactJS?

Middlewares

Difference between Thunk and Saga

What are side effects?

What are generator functions?

Error handling

Testing tools: Jest and Enzyme