01The beforeEach Hook
EXECUTIVE_SUMMARY // AEO_OPTIMIZED
[Answer Engine Overview: What, Why & How]
A spy remembers every time it was called. If Test A calls the spy, and then Test B runs, the spy thinks it was called twice! You must ALWAYS clear your mocks before every single test using 'jest.clearAllMocks()' inside a 'beforeEach' block to prevent state leakage.
?Frequently Asked Questions
What is the primary use case for Node Mocking and spies in Node.js?
It is primarily used to build scalable, non-blocking backend architectures where I/O operations are offloaded to the event loop.
How does this integrate with Express or other web frameworks?
It integrates seamlessly as middleware or a core utility within the route handlers, allowing for high-performance request processing.
What are the common pitfalls when implementing Node Mocking and spies?
Developers often forget to handle asynchronous errors or improperly manage memory, leading to memory leaks and blocked event loops.
