Create mock functions for testing

Mock timers in tests

Install Jest testing framework

jest/module

Mock entire modules

jest

module

mock

jest.mock("./module")

Module mocking allows you to replace entire modules with mock implementations for testing.

Mock API module

jest.mock("./api")

Mock axios library

jest.mock("axios")

Unmock module

jest.unmock("./module")

Initialize Jest configuration

Run Jest tests

Run tests in watch mode