Vanilla Javascript Shortcut mapping

Shortcuts.js

/*
   Include this file inside your HEAD tag and add the attribute 
`shortcut-key` (or `shortcut-keys`) to any HTML element that accepts .click().

<button shortcut-keys="enter,space">Submit</button>

This code use KeyboardEvent.code to map the shortcuts. See more https://developer.mozilla.org/pt-BR/docs/Web/API/KeyboardEvent/code
*/

(function (d) {
    const keyMapping = {};
    d.addEventListener("DOMContentLoaded", function () {
        const elements = d.querySelectorAll("[shortcut-key], [shortcut-keys]");
        elements.forEach(function (elem) {
            const keys = elem.getAttribute("shortcut-key") || elem.getAttribute("shortcut-keys");

            keys.split(",").forEach(function (key) {
                if (keyMapping[key]) {
                    throw new Error(`Double mapping found for key {${key}}.`)
                }
                keyMapping[key.toLowerCase()] = function () {
                    elem.click()
                };
            })
        })
    });
    d.onkeydown = function ({code}) {
        if (!keyMapping[code.toLowerCase()])
            return;

        keyMapping[code.toLowerCase()]();
    }
})(document);