From 38d2c57016f18f809c48fc9d19357df77a34ee2b Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 24 Oct 2012 20:16:10 +0100
Subject: [PATCH] Make less.js ignore nodes in its own path so infinite
 recursion does not happen. Fixes #413

---
 lib/less/tree/mixin.js   | 23 ++++++++++++++++++-----
 lib/less/tree/ruleset.js |  1 +
 test/css/mixins.css      |  3 +++
 test/less/mixins.less    |  6 ++++++
 4 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/lib/less/tree/mixin.js b/lib/less/tree/mixin.js
index 703c96f7..d758ae95 100644
--- a/lib/less/tree/mixin.js
+++ b/lib/less/tree/mixin.js
@@ -10,14 +10,25 @@ tree.mixin.Call = function (elements, args, index, filename, important) {
 };
 tree.mixin.Call.prototype = {
     eval: function (env) {
-        var mixins, args, rules = [], match = false;
+        var mixins, args, rules = [], match = false, i, m, f, isRecursive;
 
-        for (var i = 0; i < env.frames.length; i++) {
+        for (i = 0; i < env.frames.length; i++) {
             if ((mixins = env.frames[i].find(this.selector)).length > 0) {
+            
                 args = this.arguments && this.arguments.map(function (a) {
                     return { name: a.name, value: a.value.eval(env) };
                 });
-                for (var m = 0; m < mixins.length; m++) {
+                for (m = 0; m < mixins.length; m++) {
+                    isRecursive = false;
+                    for(f = 0; f < env.frames.length; f++) {
+                        if (mixins[m] === (env.frames[f].originalRuleset || env.frames[f])) {
+                            isRecursive = true;
+                            break;
+                        }
+                    }
+                    if (isRecursive) {
+                        continue;
+                    }
                     if (mixins[m].match(args, env)) {
                         try {
                             Array.prototype.push.apply(
@@ -140,7 +151,7 @@ tree.mixin.Definition.prototype = {
         return frame;
     },
     eval: function (env, args, important) {
-        var _arguments = [], frame = this.evalParams(env, args, _arguments), context, rules, start;
+        var _arguments = [], frame = this.evalParams(env, args, _arguments), context, rules, start, ruleset;
 
         frame.rules.unshift(new(tree.Rule)('@arguments', new(tree.Expression)(_arguments).eval(env)));
 
@@ -149,9 +160,11 @@ tree.mixin.Definition.prototype = {
                 return new(tree.Rule)(r.name, r.value, '!important', r.index);
             }) : this.rules.slice(0);
 
-        return new(tree.Ruleset)(null, rules).eval({
+        ruleset = new(tree.Ruleset)(null, rules).eval({
             frames: [this, frame].concat(this.frames, env.frames)
         });
+        ruleset.originalRuleset = this;
+        return ruleset;
     },
     match: function (args, env) {
         var argsLength = (args && args.length) || 0, len, frame;
diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index 822f331e..5bef10f5 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -12,6 +12,7 @@ tree.Ruleset.prototype = {
         var ruleset = new(tree.Ruleset)(selectors, this.rules.slice(0), this.strictImports);
         var rules = [];
         
+        ruleset.originalRuleset = this;
         ruleset.root = this.root;
         ruleset.allowImports = this.allowImports;
 
diff --git a/test/css/mixins.css b/test/css/mixins.css
index c5d3b229..2a3bb0ec 100644
--- a/test/css/mixins.css
+++ b/test/css/mixins.css
@@ -106,3 +106,6 @@ h3 + * {
   background-image: "/a.png";
   background-position: center center;
 }
+.recursion {
+  color: black;
+}
diff --git a/test/less/mixins.less b/test/less/mixins.less
index 7158c2ef..e03913e0 100644
--- a/test/less/mixins.less
+++ b/test/less/mixins.less
@@ -91,3 +91,9 @@ h3 { .margin_between(15px, 5px); }
   @s: "/";
   .mixin_def( "@{s}a.png", center center);
 }
+.recursion() {
+  color: black;
+}
+.recursion {
+  .recursion();
+}