Node.js — Parse a Request URL

When a browser asks tinyserve for a file, Node hands over req.url: only the path and the query
string, still percent-encoded — '/files/report%20v2.pdf?download=1'. Before looking for a
file, the server needs the real path (/files/report v2.pdf) and the parameters.

Your task

Write parseRequestTarget(target) with the WHATWG
[`URL`](https://nodejs.org/api/url.html#the-whatwg-url-api) class and its searchParams.

Return { path, params }:

• path — the pathname, percent-decoded with decodeURIComponent.
• params — one key per query parameter. A parameter that appears once maps to its string;

one that appears several times maps to the array of its values, in order. + means a space.

• The fragment (#...) is not part of either.

If the path contains a broken escape (%E0%A4%A, a lone %), decodeURIComponent throws a
URIError: return { error: 'Bad Request' } — a server answers 400, it does not crash.

Example

parseRequestTarget('/search?q=node+streams&tag=io&tag=fs');
// → { path: '/search', params: { q: 'node streams', tag: ['io', 'fs'] } }