From b346519f6fa1dcc8bb8df4c90ac031b2908dbe09 Mon Sep 17 00:00:00 2001
From: Eli Doran <eli@elidoran.com>
Date: Sat, 17 Dec 2016 07:27:05 -0500
Subject: [PATCH 1/3] speedup array work by using push instead of concat

---
 lib/parse.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/parse.js b/lib/parse.js
index 97387a6a..c5973068 100755
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -32,8 +32,14 @@ var parseValues = function parseValues(str, options) {
             key = options.decoder(part.slice(0, pos));
             val = options.decoder(part.slice(pos + 1));
         }
+
         if (has.call(obj, key)) {
-            obj[key] = [].concat(obj[key]).concat(val);
+            var cur = obj[key];
+            if (Array.isArray(cur)) {
+                cur.push(val);
+            } else {
+                obj[key] = [cur, val];
+            }
         } else {
             obj[key] = val;
         }

From 0b2eda959e6398ccafbe6ec432e2efc4b91fa201 Mon Sep 17 00:00:00 2001
From: Eli Doran <eli@elidoran.com>
Date: Mon, 19 Dec 2016 09:47:52 -0500
Subject: [PATCH 2/3] move array combine to its own function in utils

---
 lib/parse.js |  7 +------
 lib/utils.js | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/lib/parse.js b/lib/parse.js
index c5973068..0085ef67 100755
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -34,12 +34,7 @@ var parseValues = function parseValues(str, options) {
         }
 
         if (has.call(obj, key)) {
-            var cur = obj[key];
-            if (Array.isArray(cur)) {
-                cur.push(val);
-            } else {
-                obj[key] = [cur, val];
-            }
+            obj[key] = utils.combine(obj[key], val);
         } else {
             obj[key] = val;
         }
diff --git a/lib/utils.js b/lib/utils.js
index 33c01c00..53f32d9e 100755
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -178,3 +178,23 @@ exports.isBuffer = function (obj) {
 
     return !!(obj.constructor && obj.constructor.isBuffer && obj.constructor.isBuffer(obj));
 };
+
+exports.combine = function combine(a, b) {
+    // we always use both of these, so, let's calculate them now
+    var firstIsArray  = Array.isArray(a);
+    var secondIsArray = Array.isArray(b);
+
+    // mutate `a` to append `b` and then return it
+    if (firstIsArray) {
+        secondIsArray ? a.push.apply(a, b) : a.push(b);
+        return a;
+    }
+
+    // mutate `b` to prepend `a` and then return it
+    if (secondIsArray) {
+        b.unshift(a);
+        return b;
+    }
+
+    return [a, b];
+};

From 9c6f0b13c558f097320f7a4d64941c7e6a28388d Mon Sep 17 00:00:00 2001
From: Eli Doran <eli@elidoran.com>
Date: Mon, 19 Dec 2016 10:41:31 -0500
Subject: [PATCH 3/3] add missing comment

---
 lib/utils.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/utils.js b/lib/utils.js
index efe7465d..11eadd42 100755
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -196,5 +196,6 @@ exports.combine = function combine(a, b) {
         return b;
     }
 
+    // neither are arrays, so, create a new array with both
     return [a, b];
 };