what is the best way to create test data for javascript applications?

I'm looking for a package that let me create test data for javascript applications. Is not all that relevant, but to give you some context I'm working with a react application that uses typescript. The thing is, sometimes to reacreate the data the application uses in the run time is not an easy thing to do. You may need an array of object that in turn contain an array of other type of objects, each containing data in some particular format. The task can easily become a chore all by itself.

So I'm looking for somewhat that helps me to the the setup of the data to be able to test the application with data that resembles the real data.

For example, if you have worked with Ruby on Rails there is a good change you know factory_bot Is a tool that let you create templates of objects with data you can provide in the template, it also let you override the data partially, when you are creating the data. I'm looking for something similar in javascript, any idea or suggestion?