Object Diagnostics is a JavaScript library that can be used to automatically call a diagnostics method on an object after any operation that could potentially change its state.

Installation

npm install --save object-diagnostics

Usage

import { ObjectDiagnostics, assert } from 'object-diagnostics';

const objectWithDiagnostics = new ObjectDiagnostics().addTo(myObj);

Using JavaScript proxies, Object Diagnostics intercepts all object method calls and property accesses, including modifications and deletions. It expects a public method named diagnostics to be defined on the object, which contains checks to validate the object's internal state. After each intercepted operation, this method is automatically invoked.

Object Diagnostics disables itself if NODE_ENV is available and set to 'production'. The library also includes an assert function that is similarly disabled in production.