@remix-run/web-fetch/src/utils/get-search.js

Web API compatible fetch implementation

/**
 * @param {URL} parsedURL 
 * @returns {string}
 */
export const getSearch = parsedURL => {
	if (parsedURL.search) {
		return parsedURL.search;
	}

	const lastOffset = parsedURL.href.length - 1;
	const hash = parsedURL.hash || (parsedURL.href[lastOffset] === '#' ? '#' : '');
	return parsedURL.href[lastOffset - hash.length] === '?' ? '?' : '';
};