From 7fdea17d97527a2b3a755fb84cac405a21fad3e2 Mon Sep 17 00:00:00 2001
From: GoalSmashers <jakub@goalsmashers.com>
Date: Thu, 14 Nov 2013 09:31:30 +0100
Subject: [PATCH] Fixes #176 - hangs when `undefined` is used as a property
 value.

---
 History.md                 | 5 +++++
 lib/selectors/optimizer.js | 2 +-
 test/unit-test.js          | 5 +++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/History.md b/History.md
index 9092156a..6ef61f3b 100644
--- a/History.md
+++ b/History.md
@@ -1,3 +1,8 @@
+[2.0.1 / 2013-xx-xx](https://github.com/GoalSmashers/clean-css/compare/v2.0.0...HEAD)
+==================
+
+* Fixed issue [#176](https://github.com/GoalSmashers/clean-css/issues/176) - hangs on `undefined` keyword.
+
 [2.0.0 / 2013-11-04](https://github.com/GoalSmashers/clean-css/compare/v1.1.7...v2.0.0)
 ==================
 
diff --git a/lib/selectors/optimizer.js b/lib/selectors/optimizer.js
index 8a344e9f..b10ae788 100644
--- a/lib/selectors/optimizer.js
+++ b/lib/selectors/optimizer.js
@@ -133,7 +133,7 @@ module.exports = function Optimizer(data, options) {
       var currentMatch = matchPositions.length - 1;
 
       while (currentMatch >= 0) {
-        if (bodies[currentMatch].indexOf(optimizedTokens[k]) > -1) {
+        if (bodies[currentMatch].indexOf(optimizedTokens[k]) > -1 && k > -1) {
           k -= 1;
           continue;
         }
diff --git a/test/unit-test.js b/test/unit-test.js
index 9faaa436..42eba554 100644
--- a/test/unit-test.js
+++ b/test/unit-test.js
@@ -1249,6 +1249,11 @@ title']{display:block}",
     'when complex selector overriden by complex selectors': [
       '.one>.two,.three{color:red;line-height:1rem}#zero,.one>.two,.three,.www{color:#fff;margin:0}a{color:red}.one>.two,.three{line-height:2rem;font-size:1.5rem}',
       '#zero,.one>.two,.three,.www{color:#fff;margin:0}a{color:red}.one>.two,.three{line-height:2rem;font-size:1.5rem}'
+    ],
+    'when undefined is used as a value': '.one{text-shadow:undefined}p{color:red}.one{font-size:12px}',
+    'when undefined is used as a value with reduction': [
+      '.one{text-shadow:undefined}p{color:red}.one{font-size:12px;text-shadow:none}',
+      'p{color:red}.one{font-size:12px;text-shadow:none}'
     ]
   }),
   'same bodies': cssContext({
-- 
2.34.1