test/public/themes/simple/_grunt/node_modules/decamelize/index.js

'use strict';
module.exports = function (str, sep) {
	if (typeof str !== 'string') {
		throw new TypeError('Expected a string');
	}

	return str.replace(/([a-z\d])([A-Z])/g, '$1' + (sep || '_') + '$2').toLowerCase();
};