babel-plugin-event-on-class-extend

Babel Plugin For Event On Class Extend

Demo

Run Example To See Compiled Output

Stack Overflow Answer

Changelog

NPM Package

Install

npm i -D babel-plugin-event-on-class-extend

Add this plugin to your babel config file or add it from the cli

Babel Config

{
	"plugins": ["babel-plugin-event-on-class-extend"]
}

CLI

npx babel ... --plugins=babel-plugin-event-on-class-extend

Usage

class X {
	static name = '"I\'m X"'

	public instanceMethod() {}

	// new (...args: any[]) => X Prevent calling instance method
	static onExtend(targetClass: new (...args: any[]) => X) {
		console.log(`Class X is extended by ${targetClass.name}`)
		// targetClass.instanceMethod() This will throw error
	}
}

class Y extends X {
	static name = '"I\'m Y"'
}

// X?.onExtend(Y) will be called here

This will output Class X is extended by "I'm Y" when ran.

Options

How To Use Plugin Options

Change the plugin usage to this in babel config file

{
	"plugins": [
		[
			"babel-plugin-event-on-class-extend",
			{ "staticCallbackName": "onExtend" }
		]
	]
}

List

Option	Description	Default	Required
staticCallbackName	Change the default static method callback name	onExtend	false
classOptionalChain	Enable class optional operator. X?. optional chain	false	false
passDerivedClassAsParameter	If disable derived class will not be passed to onExtend as parameter false	true	false