Is it possible to JSDoc a custom EventEmitter with the event's proper callback params?

user_14313366 0
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I found a similar question here. However, even though it lists all the possible events, it doesn't include the callback params when I chose an event to listen to.

Here's a sample code

class BotClient extends EventEmitter {
    constructor() {
        super();
    };
    
    /**
     * @typedef {['ready' | 'messageCreate', ...any[]]} ClientEventsList
     */

    /**
     * @param {ClientEventsList} eventArg
     */
    addListener(...eventArg) {
        super.addListener(...eventArg);
    };
    /**
     * @param {ClientEventsList} eventArg
     */
    on(...eventArg) {
        super.on(...eventArg);
    };
};
eventemitter jsdoc javascript
1 Answers

Install the tiny-typed-emitter package. It doesn't add any overhead.

Library adds no overhead. All it does is it simply reexports renamed EventEmitter with customized typings. You can check lib/index.js to see the exported code.

And then declare BotClient in javascript with JSDocs as so:

const { TypedEmitter } = require("tiny-typed-emitter");

/**
 * @extends {TypedEmitter<{
     'ready': (value: boolean) => void
     'messageCreate': (message: string) => void
   }>}
 */
class BotClient extends TypedEmitter {
  constructor() {
      super();
  };
};

This way both the event and the event's arguments are going to be typed.

index.js

Screenshot

user_28283410
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