Fix searchParams setter dropping the value when a URL is set

[chatman-media]

Problem

Assigning to options.searchParams directly on an Options instance silently drops the new value. The query string the request is sent with is unchanged.

This happens outside the option-merging that the constructor uses internally — most notably in a beforeRequest hook, where the docs explicitly encourage mutating options:

import got from 'got';

await got('https://example.com', {
	searchParams: {old: 'value'},
	hooks: {
		beforeRequest: [
			options => {
				options.searchParams = {foo: 'bar'};
			},
		],
	},
});
//=> request goes to https://example.com/?old=value
//   expected: https://example.com/?foo=bar

The searchParams documentation states the value "will override the query string in url", so the request above should be sent with ?foo=bar.

The same applies to a fresh Options instance with no URL yet:

const options = new Options();
options.searchParams = {foo: 'bar'};
options.searchParams.toString(); //=> '' (expected 'foo=bar')

Cause

In the searchParams setter, the incoming value is normalized into a local updated URLSearchParams. The merging branch consumes updated, but both non-merging branches wrote/stored searchParameters (the existing params) instead of updated, so the new value was never applied:

} else if (url) {
	url.search = searchParameters.toString(); // ignores `updated`
} else {
	this.#internals.searchParams = searchParameters; // ignores `updated`
}

The normal got(url, {searchParams}) path was unaffected because it goes through the merging branch, which is why this wasn't caught earlier.

Fix

Use updated in the non-merging branches so the assignment overrides the query string as documented. The merging branch is unchanged.

Added two regression tests covering overriding searchParams from a beforeRequest hook with both an object and a string. Both fail before the change and pass after. The existing arguments, normalize-arguments, hooks, and pagination suites remain green (tsc --noEmit and xo are also clean).

[sindresorhus]

One thing to fix before merging: direct assignment on a bare Options instance now works, but assigning a URLSearchParams stores the caller-owned object by reference:

const parameters = new URLSearchParams("foo=bar");
const options = new Options();
options.searchParams = parameters;
parameters.set("foo", "changed");
console.log(options.searchParams.toString()); // foo=changed

That seems accidently inconsistent with the constructor / extend path, which clones URLSearchParams. The no-URL assignment branch should store a fresh copy instead.

[chatman-media]

Good catch, now cloning the URLSearchParams so the caller's object isn't stored by reference. Added a regression test that mutates the caller's instance after assignment and asserts the stored options are unchanged (fails before, passes after).