• Home
  • How to mock nested function in jest? – JavaScript

How to mock nested function in jest? – JavaScript

To mock a nested function in Jest, you can use the jest.spyOn method. This method allows you to mock a specific function of an object.

Here is an example of how to use jest.spyOn to mock a nested function:

const myObject = {
nestedFunction: () => {
// code for nested function
}
}

// mock the nested function
jest.spyOn(myObject, 'nestedFunction').mockImplementation(() => {
// code for mocked implementation of the nested function
});

// the nested function will now be replaced with the mocked implementation

Alternatively, you can use the jest.mock method to mock the entire object, including all of its functions. This can be useful if you want to mock all functions of the object at once.

Here is an example of how to use jest.mock to mock an entire object:

const myObject = {
nestedFunction: () => {
// code for nested function
}
}

// mock the entire object
jest.mock('myObject', () => {
return {
nestedFunction: () => {
// code for mocked implementation of the nested function
}
}
});

// all functions of the object will now be replaced with the mocked implementations

I hope this helps! Let me know if you have any questions.