Fix dnsLookup option type to accept Node.js dns.lookup

Fixes #2426

Author: sindresorhus

source/core/options.ts

@@ -12,7 +12,7 @@ import http, {
 	type ClientRequest,
 } from 'node:http';
 import type {Readable} from 'node:stream';
-import type {Socket} from 'node:net';
+import type {Socket, LookupFunction} from 'node:net';
 import is, {assert} from '@sindresorhus/is';
 import lowercaseKeys from 'lowercase-keys';
 import CacheableLookup from 'cacheable-lookup';
@@ -1990,11 +1990,11 @@ export default class Options {
 		throw new Error('The `searchParameters` option does not exist. Use `searchParams` instead.');
 	}
 
-	get dnsLookup(): CacheableLookup['lookup'] | undefined {
+	get dnsLookup(): LookupFunction | undefined {
 		return this._internals.dnsLookup;
 	}
 
-	set dnsLookup(value: CacheableLookup['lookup'] | undefined) {
+	set dnsLookup(value: LookupFunction | undefined) {
 		assertAny('dnsLookup', [is.function, is.undefined], value);
 
 		this._internals.dnsLookup = value;

test/http.ts

@@ -377,6 +377,21 @@ test('ClientRequest can throw before promise resolves', async t => {
 	t.true(['EINVAL', 'EHOSTUNREACH', 'ETIMEDOUT', 'ERR_INVALID_IP_ADDRESS'].includes(error!.code));
 });
 
+test('dnsLookup option accepts Node.js dns.lookup', withServer, async (t, server, got) => {
+	const dns = await import('node:dns');
+
+	server.get('/', (_request, response) => {
+		response.end('ok');
+	});
+
+	// This should work without type casting (regression test for #2426)
+	const {body} = await got('', {
+		dnsLookup: dns.lookup,
+	});
+
+	t.is(body, 'ok');
+});
+
 test('status code 200 has response ok is true', withServer, async (t, server, got) => {
 	server.get('/', (_request, response) => {
 		response.statusCode = 200;

test/timeout.ts

@@ -638,20 +638,15 @@ test.serial('doesn\'t throw on early lookup', withServerAndFakeTimers, async (t,
 			lookup: 1,
 		},
 		retry: {limit: 0},
-		// @ts-expect-error Testing custom dnsLookup implementation
 		dnsLookup(_hostname, options, callback) {
 			if (typeof options === 'function') {
 				callback = options;
 				// Call with default (non-all) signature
-				// @ts-expect-error Complex DNS lookup callback overloading
 				callback(null, '127.0.0.1', 4);
-			// @ts-expect-error Complex DNS lookup callback overloading - options.all check
 			} else if (options.all) {
 				// When options.all is true, callback expects an array of address objects
-				// @ts-expect-error Complex DNS lookup callback overloading
 				callback(null, [{address: '127.0.0.1', family: 4}]);
 			} else {
-				// @ts-expect-error Complex DNS lookup callback overloading
 				callback(null, '127.0.0.1', 4);
 			}
 		},