Proxyquire
Proxyquire is a Node.js testing utility that allows developers to override dependencies during unit tests by proxying Node.js's require calls. It enables mocking or stubbing of modules without modifying the original source code, making it easier to isolate and test specific components. This tool is particularly useful for testing modules that have external dependencies, such as file systems, databases, or third-party APIs.
Developers should use Proxyquire when writing unit tests in Node.js applications to mock dependencies and ensure tests are isolated and deterministic. It is ideal for scenarios where you need to test a module in isolation without relying on the actual implementation of its dependencies, such as when testing code that interacts with external services or complex internal modules. This helps improve test reliability and speed by avoiding side effects from real dependencies.