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📣 Why Promises Should Be Mockable

📣 Why Promises Should Be Mockable “Asynchronous code is easy to write — but hard to test.” Promises revolutionized async programming by replacing callback hell with chainable logic. But when it comes to   testing , native Promises behave like   black boxes : once a Promise starts, it runs independently — out of your control. If your app depends on multiple async sources — APIs, WebSockets, or events — you likely faced this problem: you can’t   pause ,   manipulate , or   mock   Promises mid-flow. That’s exactly what   MockChain   solves. 💡 The Idea MockChain   is a drop-in replacement for   Promise , designed for one purpose: To make asynchronous operations   controllable, testable, and deterministic . Instead of waiting for a real async event, you can inject outcomes in your tests — as if the async process had completed. import { MockChain } from '@fizzwiz/mockchain' ; // In your code, implement an async flow by a MockChain ...