From 1ba622dd8dc8a44f072a9e5a89bf19986313d2cd Mon Sep 17 00:00:00 2001
From: Marcel Jackwerth <marcel@northdocks.com>
Date: Fri, 17 Feb 2012 11:57:31 +0100
Subject: [PATCH] fixed a bug when using @media with mixins

---
 lib/less/tree/media.js | 27 ++++++++++++++-------------
 test/css/media.css     | 26 ++++++++++++++++++++++++++
 test/less/media.less   | 20 ++++++++++++++++++++
 3 files changed, 60 insertions(+), 13 deletions(-)

diff --git a/lib/less/tree/media.js b/lib/less/tree/media.js
index 4b5d44db..2b7b26e5 100644
--- a/lib/less/tree/media.js
+++ b/lib/less/tree/media.js
@@ -22,22 +22,23 @@ tree.Media.prototype = {
             env.mediaBlocks = [];
             env.mediaPath = [];
         }
-
-        env.mediaBlocks.push(this);
+        
+        var blockIndex = env.mediaBlocks.length;
         env.mediaPath.push(this);
+        env.mediaBlocks.push(this);
 
-        this.features = this.features.eval(env);
-        env.frames.unshift(this);
-        this.ruleset = this.ruleset.eval(env);
+        var media = new(tree.Media)([], []);
+        media.features = this.features.eval(env);
+        
+        env.frames.unshift(this.ruleset);
+        media.ruleset = this.ruleset.eval(env);
         env.frames.shift();
-
+        
+        env.mediaBlocks[blockIndex] = media;
         env.mediaPath.pop();
 
-        if (env.mediaPath.length === 0) {
-            return this.evalTop(env);
-        } else {
-            return this.evalNested(env);
-        }
+        return env.mediaPath.length === 0 ? media.evalTop(env) :
+                    media.evalNested(env)
     },
     variable: function (name) { return tree.Ruleset.prototype.variable.call(this.ruleset, name) },
     find: function () { return tree.Ruleset.prototype.find.apply(this.ruleset, arguments) },
@@ -93,9 +94,9 @@ tree.Media.prototype = {
         return new(tree.Ruleset)([], []);
     },
     permute: function (arr) {
-      if (arr.length == 0) {
+      if (arr.length === 0) {
           return [];
-      } else if (arr.length == 1) {
+      } else if (arr.length === 1) {
           return arr[0];
       } else {
           var result = [];
diff --git a/test/css/media.css b/test/css/media.css
index a591017e..bbfad74d 100644
--- a/test/css/media.css
+++ b/test/css/media.css
@@ -48,3 +48,29 @@
     width: 100%;
   }
 }
+.a {
+  background: black;
+}
+@media handheld {
+  .a {
+    background: white;
+  }
+}
+@media handheld and (max-width: 100px) {
+  .a {
+    background: red;
+  }
+}
+.b {
+  background: black;
+}
+@media handheld {
+  .b {
+    background: white;
+  }
+}
+@media handheld and (max-width: 200px) {
+  .b {
+    background: red;
+  }
+}
diff --git a/test/less/media.less b/test/less/media.less
index 6a3749b7..1196a524 100644
--- a/test/less/media.less
+++ b/test/less/media.less
@@ -52,4 +52,24 @@ body {
             width: 100%;
         }
     }
+}
+
+.mediaMixin(@fallback: 200px) {
+    background: black;
+
+    @media handheld {
+        background: white;
+
+        @media (max-width: @fallback) {
+            background: red;
+        }
+    }
+}
+
+.a {
+  .mediaMixin(100px);
+}
+
+.b {
+  .mediaMixin();
 }
\ No newline at end of file