Method to autobind methods in NodeJS

autobind.js

// Based logic on example for discovering properties here: https://stackoverflow.com/questions/31054910/get-functions-methods-of-a-class
// This takes a class instance and returns an object with the objects bound to the instance
// Written, mainly to see if it could be done to avoid having to do individual explcit binds when
// registering with express router
function autoBind(instance) {

    let obj = instance;
    let props = []

    do {
        const l = Object.getOwnPropertyNames(obj)
            .concat(Object.getOwnPropertySymbols(obj).map(s => s.toString()))
            .sort()
            .filter((p, i, arr) =>
                typeof obj[p] === 'function' &&  //only the methods
                p !== 'constructor' &&           //not the constructor
                (i == 0 || p !== arr[i - 1]) &&  //not overriding in this prototype
                props.indexOf(p) === -1          //not overridden in a child
            )
        props = props.concat(l)
    }
    while (
        (obj = Object.getPrototypeOf(obj)) &&   //walk-up the prototype chain
        Object.getPrototypeOf(obj)              //not the the Object prototype methods (hasOwnProperty, etc...)
    )

    const autoboundObj = {};

    props.forEach((prop) => {
        autoboundObj[prop] = instance[prop].bind(instance);
    });

    return autoboundObj;
}

export default autoBind;