Bind this for all methods in ES6 classes

binder.js

'use strict';

class Binder {}

Binder.getAllMethods = function(instance, cls) {
  return Object.getOwnPropertyNames(Object.getPrototypeOf(instance))
    .filter(name => {
      let method = instance[name];
      return !(!(method instanceof Function) || method === cls);
    });
}

Binder.bind = function(instance, cls) {
  getAllMethods(instance, cls)
    .forEach(mtd => {
      instance[mtd] = instance[mtd].bind(instance);
    })
}

module.exports = Binder;

To use the binder:

const Binder = require('./binder');
class Test{
    constructor(){
        // ...
        Binder.bind(this, Test)
    }
}

logical mind explosion:

return !(!(method instanceof Function) || method === cls);

ez logic

return method instanceof Function && method !== cls;

why? because De Morgan

!(a ∨ b) === !a ∧ !b

therefore

!(!a ∨ b) === a ∧ !b

(where ∨ is logical OR and ∧ is logical AND)

thanks for this @anhldbk !

This is cleaner (pun intended)

function bindMethods() {
    Object.getOwnPropertyNames(Object.getPrototypeOf(this))
        .map(key => {
            if (this[key] instanceof Function && key !== 'constructor')
                this[key] = this[key].bind(this)
        })
}

class Bla {
    constructor(name) {
        this.name = name
        
        bindMethods.call(this)        
    }
    
    greet () { console.log(`Hello, ${this.name}`) }
}

@ivangeorgiew but what is the pun? I'm confused.