Method Chain

jquery-method-chain.js

const jQuery = function( selector, context ) {
  return new jQuery.fn.init( selector, context );
}
jQuery.fn = jQuery.prototype = {
    pushStack: function (elem) {
        const ret = elem;
        ret.prevObject = this;
        return ret;
    },
    find: function (selector) {
        return this.pushStack(jQuery(selector, this[0]));
    },
    end: function (selector) {
        return this.prevObject
    }
};
jQuery.fn.init = function( selector,  context) {
    const node = context || document;
    this[ 0 ] = node.querySelector(selector);
    return this;
}
jQuery.fn.init.prototype = jQuery.fn;
console.log(jQuery('body').find('main').find('div'));