From a6fdc5cf4c91c43508c56e68ff94353300b54af7 Mon Sep 17 00:00:00 2001
From: Antoine du Hamel <duhamelantoine1995@gmail.com>
Date: Tue, 10 May 2022 11:10:03 +0200
Subject: [PATCH] dns: accept `'IPv4'` and `'IPv6'` as valid `family` values

Refs: https://github.com/nodejs/node/issues/43014
---
 doc/api/dns.md                                   | 16 +++++++++++-----
 lib/dns.js                                       | 14 ++++++++++++--
 test/internet/test-dns-lookup.js                 |  2 +-
 .../parallel/test-net-socket-ready-without-cb.js |  2 +-
 4 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/doc/api/dns.md b/doc/api/dns.md
index c9e901da677283..0d281fdffe051f 100644
--- a/doc/api/dns.md
+++ b/doc/api/dns.md
@@ -179,6 +179,11 @@ section if a custom port is used.
 <!-- YAML
 added: v0.1.90
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: For compatibility with `node:net`, when passing an option
+                 object the `family` option can be the string `'IPv4'` or the
+                 string `'IPv6'`.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41678
     description: Passing an invalid callback to the `callback` argument
@@ -197,9 +202,10 @@ changes:
 
 * `hostname` {string}
 * `options` {integer | Object}
-  * `family` {integer} The record family. Must be `4`, `6`, or `0`. The value
-    `0` indicates that IPv4 and IPv6 addresses are both returned. **Default:**
-    `0`.
+  * `family` {integer|string} The record family. Must be `4`, `6`, or `0`. For
+    backward compatibility reasons,`'IPv4'` and `'IPv6'` are interpreted as `4`
+    and `6` respectively. The value `0` indicates that IPv4 and IPv6 addresses
+    are both returned. **Default:** `0`.
   * `hints` {number} One or more [supported `getaddrinfo` flags][]. Multiple
     flags may be passed by bitwise `OR`ing their values.
   * `all` {boolean} When `true`, the callback returns all resolved addresses in
@@ -219,8 +225,8 @@ changes:
 
 Resolves a host name (e.g. `'nodejs.org'`) into the first found A (IPv4) or
 AAAA (IPv6) record. All `option` properties are optional. If `options` is an
-integer, then it must be `4` or `6` – if `options` is not provided, then IPv4
-and IPv6 addresses are both returned if found.
+integer, then it must be `4` or `6` – if `options` is `0` or not provided, then
+IPv4 and IPv6 addresses are both returned if found.
 
 With the `all` option set to `true`, the arguments for `callback` change to
 `(err, addresses)`, with `addresses` being an array of objects with the
diff --git a/lib/dns.js b/lib/dns.js
index 2e1a37b0818a14..bec56665b3d634 100644
--- a/lib/dns.js
+++ b/lib/dns.js
@@ -140,8 +140,18 @@ function lookup(hostname, options, callback) {
       validateHints(hints);
     }
     if (options?.family != null) {
-      validateOneOf(options.family, 'options.family', validFamilies, true);
-      family = options.family;
+      switch (options.family) {
+        case 'IPv4':
+          family = 4;
+          break;
+        case 'IPv6':
+          family = 6;
+          break;
+        default:
+          validateOneOf(options.family, 'options.family', validFamilies, true);
+          family = options.family;
+          break;
+      }
     }
     if (options?.all != null) {
       validateBoolean(options.all, 'options.all');
diff --git a/test/internet/test-dns-lookup.js b/test/internet/test-dns-lookup.js
index d4e3d6d1eb762b..6e2714ecad07d0 100644
--- a/test/internet/test-dns-lookup.js
+++ b/test/internet/test-dns-lookup.js
@@ -47,7 +47,7 @@ dns.lookup(addresses.NOT_FOUND, {
 
 assert.throws(
   () => dnsPromises.lookup(addresses.NOT_FOUND, {
-    family: 'IPv4',
+    family: 'ipv4',
     all: 'all'
   }),
   { code: 'ERR_INVALID_ARG_VALUE' }
diff --git a/test/parallel/test-net-socket-ready-without-cb.js b/test/parallel/test-net-socket-ready-without-cb.js
index 29da68e173c193..1ad5db4760dc1e 100644
--- a/test/parallel/test-net-socket-ready-without-cb.js
+++ b/test/parallel/test-net-socket-ready-without-cb.js
@@ -9,7 +9,7 @@ const net = require('net');
 const server = net.createServer(common.mustCall(function(conn) {
   conn.end();
   server.close();
-})).listen(0, 'localhost', common.mustCall(function() {
+})).listen(0, common.mustCall(function() {
   const client = new net.Socket();
 
   client.on('ready', common.mustCall(function() {