From f787bfc926263493847af34eb6545ca10d015b30 Mon Sep 17 00:00:00 2001
From: Sindre Sorhus <sindresorhus@gmail.com>
Date: Fri, 21 Dec 2018 14:39:57 +0100
Subject: [PATCH] Don't mutate the user-supplied object

---
 index.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/index.js b/index.js
index 4a98fc4..c1d6585 100644
--- a/index.js
+++ b/index.js
@@ -13,7 +13,9 @@ const isAvailable = options => new Promise((resolve, reject) => {
 	});
 });
 
-const getPort = (options = {}) => {
+const getPort = options => {
+	options = Object.assign({}, options);
+
 	if (typeof options.port === 'number') {
 		options.port = [options.port];
 	}