From d5f29b6b33f15a782b23bd76d56da5ea09d0b770 Mon Sep 17 00:00:00 2001
From: Jake Bellacera <hi@jakebellacera.com>
Date: Fri, 23 Aug 2013 15:45:09 -0700
Subject: [PATCH 01/29] Adding gsub function

---
 lib/less/functions.js    | 7 +++++++
 test/css/functions.css   | 1 +
 test/less/functions.less | 1 +
 3 files changed, 9 insertions(+)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index fbde54ff..9968c59d 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -213,6 +213,13 @@ tree.functions = {
     escape: function (str) {
         return new(tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
     },
+    gsub: function (str, regexp, replacement) {
+        var str = str.value;
+
+        str = str.replace(new RegExp(regexp.value, "g"), replacement.value);
+
+        return new(tree.Quoted)('"' + str + '"', str)
+    },
     '%': function (quoted /* arg, arg, ...*/) {
         var args = Array.prototype.slice.call(arguments, 1),
             str = quoted.value;
diff --git a/test/css/functions.css b/test/css/functions.css
index eacebd8d..499b614c 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -8,6 +8,7 @@
 }
 #built-in {
   escaped: -Some::weird(#thing, y);
+  gsub: "Hello, World!";
   lighten: #ffcccc;
   darken: #330000;
   saturate: #203c31;
diff --git a/test/less/functions.less b/test/less/functions.less
index f60dab47..d84ae6bd 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -12,6 +12,7 @@
 #built-in {
   @r: 32;
   escaped: e("-Some::weird(#thing, y)");
+  gsub: gsub("Hello, Foo.", "Foo\.$", "World!");
   lighten: lighten(#ff0000, 40%);
   darken: darken(#ff0000, 40%);
   saturate: saturate(#29332f, 20%);

From d4e15e29f8a75ce2c8256e335b77898769e95c49 Mon Sep 17 00:00:00 2001
From: Jake Bellacera <hi@jakebellacera.com>
Date: Fri, 23 Aug 2013 15:45:09 -0700
Subject: [PATCH 02/29] Adding gsub function

---
 lib/less/functions.js    | 7 +++++++
 test/css/functions.css   | 1 +
 test/less/functions.less | 1 +
 3 files changed, 9 insertions(+)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index fbde54ff..9968c59d 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -213,6 +213,13 @@ tree.functions = {
     escape: function (str) {
         return new(tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
     },
+    gsub: function (str, regexp, replacement) {
+        var str = str.value;
+
+        str = str.replace(new RegExp(regexp.value, "g"), replacement.value);
+
+        return new(tree.Quoted)('"' + str + '"', str)
+    },
     '%': function (quoted /* arg, arg, ...*/) {
         var args = Array.prototype.slice.call(arguments, 1),
             str = quoted.value;
diff --git a/test/css/functions.css b/test/css/functions.css
index eacebd8d..499b614c 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -8,6 +8,7 @@
 }
 #built-in {
   escaped: -Some::weird(#thing, y);
+  gsub: "Hello, World!";
   lighten: #ffcccc;
   darken: #330000;
   saturate: #203c31;
diff --git a/test/less/functions.less b/test/less/functions.less
index f60dab47..d84ae6bd 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -12,6 +12,7 @@
 #built-in {
   @r: 32;
   escaped: e("-Some::weird(#thing, y)");
+  gsub: gsub("Hello, Foo.", "Foo\.$", "World!");
   lighten: lighten(#ff0000, 40%);
   darken: darken(#ff0000, 40%);
   saturate: saturate(#29332f, 20%);

From 170042fb02532632a05759f00c9851e0a882dea3 Mon Sep 17 00:00:00 2001
From: Jake Bellacera <hi@jakebellacera.com>
Date: Fri, 23 Aug 2013 16:26:39 -0700
Subject: [PATCH 03/29] Adding capture group test case

---
 test/css/functions.css   | 1 +
 test/less/functions.less | 1 +
 2 files changed, 2 insertions(+)

diff --git a/test/css/functions.css b/test/css/functions.css
index 499b614c..3e11d944 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -9,6 +9,7 @@
 #built-in {
   escaped: -Some::weird(#thing, y);
   gsub: "Hello, World!";
+  gsub-captured: "This is a new string.";
   lighten: #ffcccc;
   darken: #330000;
   saturate: #203c31;
diff --git a/test/less/functions.less b/test/less/functions.less
index d84ae6bd..cf81dc54 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -13,6 +13,7 @@
   @r: 32;
   escaped: e("-Some::weird(#thing, y)");
   gsub: gsub("Hello, Foo.", "Foo\.$", "World!");
+  gsub-captured: gsub("This is a string.", "(string)\.$", "new $1.");
   lighten: lighten(#ff0000, 40%);
   darken: darken(#ff0000, 40%);
   saturate: saturate(#29332f, 20%);

From 089bf1b78a299b029609d66306e5230f08ff311e Mon Sep 17 00:00:00 2001
From: Jake Bellacera <jakeb@eleveninc.com>
Date: Thu, 6 Feb 2014 23:29:14 -0800
Subject: [PATCH 04/29] Adding replace function

* renamed gsub function to replace
* reordered replace's function arguments to be much more readable
* added support for replacement (Regexp) options
---
 lib/less/functions.js    | 8 ++++----
 test/css/functions.css   | 5 +++--
 test/less/functions.less | 5 +++--
 3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index 883451a3..96f9c3bf 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -218,12 +218,12 @@ tree.functions = {
     escape: function (str) {
         return new(tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
     },
-    gsub: function (str, regexp, replacement) {
-        var str = str.value;
+    replace: function (subject, pattern, replacement, options) {
+        var str = subject.value;
 
-        str = str.replace(new RegExp(regexp.value, "g"), replacement.value);
+        str = str.replace(new RegExp(pattern.value, options ? options.value : ""), replacement.value);
 
-        return new(tree.Quoted)('"' + str + '"', str)
+        return new(tree.Quoted)('"' + str + '"', str);
     },
     '%': function (quoted /* arg, arg, ...*/) {
         var args = Array.prototype.slice.call(arguments, 1),
diff --git a/test/css/functions.css b/test/css/functions.css
index fa5ea89b..0ba7a279 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -8,8 +8,6 @@
 }
 #built-in {
   escaped: -Some::weird(#thing, y);
-  gsub: "Hello, World!";
-  gsub-captured: "This is a new string.";
   lighten: #ffcccc;
   darken: #330000;
   saturate: #203c31;
@@ -47,6 +45,9 @@
   contrast-dark-thresh-per: #eeeeee;
   contrast-high-thresh-per: #eeeeee;
   contrast-low-thresh-per: #111111;
+  replace: "Hello, World!";
+  replace-captured: "This is a new string.";
+  replace-options: "2 + 2 = 4";
   format: "rgb(32, 128, 64)";
   format-string: "hello world";
   format-multiple: "hello earth 2";
diff --git a/test/less/functions.less b/test/less/functions.less
index eb7df7e2..cac404f4 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -12,8 +12,6 @@
 #built-in {
   @r: 32;
   escaped: e("-Some::weird(#thing, y)");
-  gsub: gsub("Hello, Foo.", "Foo\.$", "World!");
-  gsub-captured: gsub("This is a string.", "(string)\.$", "new $1.");
   lighten: lighten(#ff0000, 40%);
   darken: darken(#ff0000, 40%);
   saturate: saturate(#29332f, 20%);
@@ -51,6 +49,9 @@
   contrast-dark-thresh-per: contrast(#000, #111111, #eeeeee, 50%);
   contrast-high-thresh-per: contrast(#555, #111111, #eeeeee, 60%);
   contrast-low-thresh-per: contrast(#555, #111111, #eeeeee, 10%);
+  replace: replace("Hello, Mars.", "Mars\.", "World!");
+  replace-captured: replace("This is a string.", "(string)\.$", "new $1.");
+  replace-options: replace("One + one = 4", "one", "2", "gi");
   format: %("rgb(%d, %d, %d)", @r, 128, 64);
   format-string: %("hello %s", "world");
   format-multiple: %("hello %s %d", "earth", 2);

From 98f48bcb7890342304df8f5a2a3b1a07ddb5afcb Mon Sep 17 00:00:00 2001
From: Jake Bellacera <jakeb@eleveninc.com>
Date: Thu, 6 Feb 2014 23:41:18 -0800
Subject: [PATCH 05/29] Replacing replace's options to flags

---
 lib/less/functions.js    | 4 ++--
 test/css/functions.css   | 2 +-
 test/less/functions.less | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index 96f9c3bf..7b11959c 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -218,10 +218,10 @@ tree.functions = {
     escape: function (str) {
         return new(tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
     },
-    replace: function (subject, pattern, replacement, options) {
+    replace: function (subject, pattern, replacement, flags) {
         var str = subject.value;
 
-        str = str.replace(new RegExp(pattern.value, options ? options.value : ""), replacement.value);
+        str = str.replace(new RegExp(pattern.value, flags ? flags.value : ""), replacement.value);
 
         return new(tree.Quoted)('"' + str + '"', str);
     },
diff --git a/test/css/functions.css b/test/css/functions.css
index 0ba7a279..e7ea76c0 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -47,7 +47,7 @@
   contrast-low-thresh-per: #111111;
   replace: "Hello, World!";
   replace-captured: "This is a new string.";
-  replace-options: "2 + 2 = 4";
+  replace-with-flags: "2 + 2 = 4";
   format: "rgb(32, 128, 64)";
   format-string: "hello world";
   format-multiple: "hello earth 2";
diff --git a/test/less/functions.less b/test/less/functions.less
index cac404f4..7420cc8a 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -51,7 +51,7 @@
   contrast-low-thresh-per: contrast(#555, #111111, #eeeeee, 10%);
   replace: replace("Hello, Mars.", "Mars\.", "World!");
   replace-captured: replace("This is a string.", "(string)\.$", "new $1.");
-  replace-options: replace("One + one = 4", "one", "2", "gi");
+  replace-with-flags: replace("One + one = 4", "one", "2", "gi");
   format: %("rgb(%d, %d, %d)", @r, 128, 64);
   format-string: %("hello %s", "world");
   format-multiple: %("hello %s %d", "earth", 2);

From f7414a1072094240c0b464ddf8f20d67e7cd88de Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Sun, 9 Feb 2014 22:20:08 +0000
Subject: [PATCH 06/29] detached rulesets

---
 build/build.yml                  |  1 +
 lib/less/index.js                |  1 +
 lib/less/parser.js               | 59 ++++++++++++++++++++++++--------
 lib/less/tree/ruleset-call.js    | 15 ++++++++
 lib/less/tree/ruleset.js         | 13 +++++++
 test/css/detached-rulesets.css   |  7 ++++
 test/less/detached-rulesets.less | 16 +++++++++
 7 files changed, 97 insertions(+), 15 deletions(-)
 create mode 100644 lib/less/tree/ruleset-call.js
 create mode 100644 test/css/detached-rulesets.css
 create mode 100644 test/less/detached-rulesets.less

diff --git a/build/build.yml b/build/build.yml
index dd4236b9..68fa2607 100644
--- a/build/build.yml
+++ b/build/build.yml
@@ -143,6 +143,7 @@ tree:
   - <%= build.lib %>/tree/quoted.js
   - <%= build.lib %>/tree/rule.js
   - <%= build.lib %>/tree/ruleset.js
+  - <%= build.lib %>/tree/ruleset-call.js
   - <%= build.lib %>/tree/selector.js
   - <%= build.lib %>/tree/unicode-descriptor.js
   - <%= build.lib %>/tree/url.js
diff --git a/lib/less/index.js b/lib/less/index.js
index 7aee17c8..b85a84f9 100644
--- a/lib/less/index.js
+++ b/lib/less/index.js
@@ -120,6 +120,7 @@ require('./tree/media');
 require('./tree/unicode-descriptor');
 require('./tree/negative');
 require('./tree/extend');
+require('./tree/ruleset-call');
 
 
 var isUrlRe = /^(?:https?:)?\/\//i;
diff --git a/lib/less/parser.js b/lib/less/parser.js
index 0f19d487..04330f7e 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -729,7 +729,7 @@ less.Parser = function Parser(env) {
                 while (current)
                 {
                     node = this.extendRule() || mixin.definition() || this.rule() || this.ruleset() ||
-                        mixin.call() || this.comment() || this.directive();
+                        mixin.call() || this.comment() || this.rulesetCall() || this.directive();
                     if (node) {
                         root.push(node);
                     } else {
@@ -1027,6 +1027,19 @@ less.Parser = function Parser(env) {
                 if (input.charAt(i) === '@' && (name = $re(/^(@[\w-]+)\s*:/))) { return name[1]; }
             },
 
+            //
+            // The variable part of a variable definition. Used in the `rule` parser
+            //
+            //     @fink();
+            //
+            rulesetCall: function () {
+                var name;
+
+                if (input.charAt(i) === '@' && (name = $re(/^(@[\w-]+)\s*\(\s*\)\s*;/))) { 
+                    return new tree.RulesetCall(name[1]); 
+                }
+            },
+
             //
             // extend syntax - used to extend selectors
             //
@@ -1126,7 +1139,7 @@ less.Parser = function Parser(env) {
 
                     while (true) {
                         if (isCall) {
-                            arg = parsers.expression();
+                            arg = parsers.blockRuleset() || parsers.expression();
                         } else {
                             parsers.comments();
                             if (input.charAt(i) === '.' && $re(/^\.{3}/)) {
@@ -1154,7 +1167,7 @@ less.Parser = function Parser(env) {
 
                         if (isCall) {
                             // Variable
-                            if (arg.value.length == 1) {
+                            if (arg.value && arg.value.length == 1) {
                                 val = arg.value[0];
                             }
                         } else {
@@ -1442,6 +1455,14 @@ less.Parser = function Parser(env) {
                 }
             },
 
+            blockRuleset: function() {
+                var block = this.block();
+                if (block) {
+                    block = new tree.Ruleset(null, block);
+                }
+                return block;
+            },
+
             //
             // div, .class, body > p {...}
             //
@@ -1484,25 +1505,33 @@ less.Parser = function Parser(env) {
                 }
             },
             rule: function (tryAnonymous) {
-                var name, value, c = input.charAt(i), important, merge;
+                var name, value, c = input.charAt(i), important, merge, isVariable;
                 save();
 
                 if (c === '.' || c === '#' || c === '&') { return; }
 
                 name = this.variable() || this.ruleProperty();
                 if (name) {
-                    // prefer to try to parse first if its a variable or we are compressing
-                    // but always fallback on the other one
-                    value = !tryAnonymous && (env.compress || (name.charAt && (name.charAt(0) === '@'))) ?
-                        (this.value() || this.anonymousValue()) :
-                        (this.anonymousValue() || this.value());
-
-                    important = this.important();
+                    isVariable = typeof name === "string";
                     
-                    // a name returned by this.ruleProperty() is always an array of the form:
-                    // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
-                    // where each item is a tree.Keyword or tree.Variable
-                    merge = name.pop && name.pop().value;
+                    if (isVariable) {
+                        value = this.blockRuleset();
+                    }
+                    
+                    if (!value) {
+                        // prefer to try to parse first if its a variable or we are compressing
+                        // but always fallback on the other one
+                        value = !tryAnonymous && (env.compress || isVariable) ?
+                            (this.value() || this.anonymousValue()) :
+                            (this.anonymousValue() || this.value());
+    
+                        important = this.important();
+                        
+                        // a name returned by this.ruleProperty() is always an array of the form:
+                        // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
+                        // where each item is a tree.Keyword or tree.Variable
+                        merge = !isVariable && name.pop().value;
+                    }
 
                     if (value && this.end()) {
                         return new (tree.Rule)(name, value, important, merge, memo, env.currentFileInfo);
diff --git a/lib/less/tree/ruleset-call.js b/lib/less/tree/ruleset-call.js
new file mode 100644
index 00000000..ec9e98d2
--- /dev/null
+++ b/lib/less/tree/ruleset-call.js
@@ -0,0 +1,15 @@
+(function (tree) {
+
+tree.RulesetCall = function (variable) {
+    this.variable = variable;
+};
+tree.RulesetCall.prototype = {
+    type: "RulesetCall",
+    accept: function (visitor) {
+    },
+    eval: function (env) {
+        return new(tree.Variable)(this.variable).eval(env);
+    }
+};
+
+})(require('../tree'));
diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index e7895760..15cc80d9 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -90,6 +90,19 @@ tree.Ruleset.prototype = {
                 rsRuleCnt += rules.length - 1;
                 i += rules.length-1;
                 ruleset.resetCache();
+            } else if (rsRules[i] instanceof tree.RulesetCall) {
+                /*jshint loopfunc:true */
+                rules = rsRules[i].eval(env).rules.filter(function(r) {
+                    if ((r instanceof tree.Rule) && r.variable) {
+                        // do not pollute the scope at all
+                        return false;
+                    }
+                    return true;
+                });
+                rsRules.splice.apply(rsRules, [i, 1].concat(rules));
+                rsRuleCnt += rules.length - 1;
+                i += rules.length-1;
+                ruleset.resetCache();
             }
         }
 
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
new file mode 100644
index 00000000..08e82bc5
--- /dev/null
+++ b/test/css/detached-rulesets.css
@@ -0,0 +1,7 @@
+.wrap-selector {
+  color: black;
+}
+.wrap-selector {
+  color: black;
+  background: white;
+}
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
new file mode 100644
index 00000000..49360763
--- /dev/null
+++ b/test/less/detached-rulesets.less
@@ -0,0 +1,16 @@
+@ruleset: {
+     color: black;
+     background: white;
+  };
+
+.wrap-mixin(@ruleset) {
+  .wrap-selector {
+      @ruleset();
+    }
+};
+
+.wrap-mixin({
+  color: black;
+});
+
+.wrap-mixin(@ruleset);
\ No newline at end of file

From 55033c77ed7942d5223b07b90e5df119fc5ea3dd Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Tue, 11 Feb 2014 22:01:26 +0000
Subject: [PATCH 07/29] more tests and name arguments for caller

---
 lib/less/parser.js               | 18 ++++++++++++++++--
 test/css/detached-rulesets.css   | 14 ++++++++++++++
 test/less/detached-rulesets.less | 19 ++++++++++++++++++-
 3 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index 4fa31f58..76f312e5 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -1182,7 +1182,17 @@ less.Parser = function Parser(env) {
                                     }
                                     expressionContainsNamed = true;
                                 }
-                                value = expect(parsers.expression);
+                                // we do not support setting a ruleset as a default variable - it doesn't make sense
+                                // and to implement it we need backtracking with multiple saves
+                                value = (isCall && parsers.blockRuleset()) || parsers.expression();
+                                if (!value) {
+                                    if (isCall) {
+                                        error("could not understand value for named argument");
+                                    } else {
+                                        returner.args = [];
+                                        return returner;
+                                    }
+                                }
                                 nameLoop = (name = val.name);
                             } else if (!isCall && $re(/^\.{3}/)) {
                                 returner.variadic = true;
@@ -1267,10 +1277,14 @@ less.Parser = function Parser(env) {
                         variadic = argInfo.variadic;
 
                         // .mixincall("@{a}");
-                        // looks a bit like a mixin definition.. so we have to be nice and restore
+                        // looks a bit like a mixin definition.. 
+                        // also
+                        // .mixincall(@a: {rule: set;});
+                        // so we have to be nice and restore
                         if (!$char(')')) {
                             furthest = i;
                             restore();
+                            return;
                         }
                         
                         parsers.comments();
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index 08e82bc5..dc706a62 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -1,7 +1,21 @@
 .wrap-selector {
   color: black;
 }
+.wrap-selector {
+  color: red;
+}
 .wrap-selector {
   color: black;
   background: white;
 }
+header {
+  background: blue;
+}
+@media screen and (min-width: 1200) {
+  header {
+    background: red;
+  }
+}
+html.lt-ie9 header {
+  background: red;
+}
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 49360763..01abdd7e 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -13,4 +13,21 @@
   color: black;
 });
 
-.wrap-mixin(@ruleset);
\ No newline at end of file
+.wrap-mixin(@ruleset: {
+  color: red;
+});
+
+.wrap-mixin(@ruleset);
+
+.desktop-and-old-ie(@rules) {
+  @media screen and (min-width: 1200) { @rules(); }
+  html.lt-ie9 &                       { @rules(); }
+}
+
+header {
+  background: blue;
+
+  .desktop-and-old-ie({
+    background: red;
+  });
+}

From 7f26515630dddc31cf95c3cc198f51acccdff230 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Tue, 11 Feb 2014 22:02:48 +0000
Subject: [PATCH 08/29] small simplification

---
 lib/less/parser.js | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index 76f312e5..064e5f27 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -1785,10 +1785,7 @@ less.Parser = function Parser(env) {
                 }
 
                 if (hasBlock) {
-                    rules = this.block();
-                    if (rules) { 
-                        rules = new(tree.Ruleset)(null, rules);
-                    }
+                    rules = this.blockRuleset();
                 }
 
                 if (rules || (!hasBlock && value && $char(';'))) {

From ed0e13a0ecd2f2bb31d2874c61d351c54803245d Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 12 Feb 2014 22:34:58 +0000
Subject: [PATCH 09/29] do not chunk inside parens so that we can predict mixin
 calls containing detached rulesets. Also now save the current chunk (may not
 be required).

---
 lib/less/parser.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index 064e5f27..fc3c1fe9 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -45,6 +45,7 @@ less.Parser = function Parser(env) {
         j,           // current chunk
         temp,        // temporarily holds a chunk's state, for backtracking
         memo,        // temporarily holds `i`, when backtracking
+        memoChunk,   //                   `j`
         furthest,    // furthest index the parser has gone to
         chunks,      // chunkified input
         current,     // current chunk
@@ -111,8 +112,8 @@ less.Parser = function Parser(env) {
         }
     };
 
-    function save()    { temp = current; memo = currentPos = i; }
-    function restore() { current = temp; currentPos = i = memo; }
+    function save()    { temp = current; memo = currentPos = i; memoChunk = j; }
+    function restore() { current = temp; currentPos = i = memo; j = memoChunk; }
 
     function sync() {
         if (i > currentPos) {
@@ -424,7 +425,7 @@ less.Parser = function Parser(env) {
                             if (--level < 0) {
                                 return fail("missing opening `{`");
                             }
-                            if (!level) { emitChunk(); }
+                            if (!level && !parenLevel) { emitChunk(); }
                             continue;
                         case 92:                        // \
                             if (parserCurrentIndex < len - 1) { parserCurrentIndex++; continue; }

From e3168e343460539556a86023833d1a033e013cba Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 12 Feb 2014 22:40:20 +0000
Subject: [PATCH 10/29] add some more failing tests

---
 test/less/detached-rulesets.less | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 01abdd7e..665fdfba 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -31,3 +31,18 @@ header {
     background: red;
   });
 }
+
+.wrap-mixin-calls-wrap(@ruleset) {
+  .wrap-mixin(@ruleset);
+};
+
+.wrap-mixin({
+  test: extra-wrap;
+  .wrap-mixin-calls-wrap({
+    test: wrapped-twice;
+  });
+});
+
+.wrap-mixin({
+  test-func: unit(90px);
+});

From e3576b9c01799ee7e033b7413c8ce1b9bdfbe805 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 12 Feb 2014 23:10:52 +0000
Subject: [PATCH 11/29] implement n level back-tracking and then don't absorb a
 parenthesis, fixing both issues with 2 new test cases

---
 lib/less/parser.js               | 26 +++++++++++++++++++-------
 test/css/detached-rulesets.css   | 10 ++++++++++
 test/less/detached-rulesets.less |  1 +
 3 files changed, 30 insertions(+), 7 deletions(-)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index fc3c1fe9..8231bf83 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -43,9 +43,7 @@ less.Parser = function Parser(env) {
     var input,       // LeSS input string
         i,           // current index in `input`
         j,           // current chunk
-        temp,        // temporarily holds a chunk's state, for backtracking
-        memo,        // temporarily holds `i`, when backtracking
-        memoChunk,   //                   `j`
+        saveStack = [],   // holds state for backtracking
         furthest,    // furthest index the parser has gone to
         chunks,      // chunkified input
         current,     // current chunk
@@ -112,8 +110,9 @@ less.Parser = function Parser(env) {
         }
     };
 
-    function save()    { temp = current; memo = currentPos = i; memoChunk = j; }
-    function restore() { current = temp; currentPos = i = memo; j = memoChunk; }
+    function save()    { currentPos = i; saveStack.push( { current: current, i: i, j: j }); }
+    function restore() { var state = saveStack.pop(); current = state.current; currentPos = i = state.i; j = state.j; }
+    function forget() { saveStack.pop(); }
 
     function sync() {
         if (i > currentPos) {
@@ -1126,6 +1125,7 @@ less.Parser = function Parser(env) {
                         }
 
                         if (parsers.end()) {
+                            forget();
                             return new(tree.mixin.Call)(elements, args, index, env.currentFileInfo, important);
                         }
                     }
@@ -1297,6 +1297,7 @@ less.Parser = function Parser(env) {
                         ruleset = parsers.block();
 
                         if (ruleset) {
+                            forget();
                             return new(tree.mixin.Definition)(name, params, ruleset, cond, variadic);
                         } else {
                             restore();
@@ -1364,10 +1365,16 @@ less.Parser = function Parser(env) {
                     this.entities.variableCurly();
 
                 if (! e) {
+                    save();
                     if ($char('(')) {
                         if ((v = this.selector()) && $char(')')) {
                             e = new(tree.Paren)(v);
+                            forget();
+                        } else {
+                            restore();
                         }
+                    } else {
+                        forget();
                     }
                 }
 
@@ -1508,6 +1515,7 @@ less.Parser = function Parser(env) {
                 }
 
                 if (selectors && (rules = this.block())) {
+                    forget();
                     var ruleset = new(tree.Ruleset)(selectors, rules, env.strictImports);
                     if (env.dumpLineNumbers) {
                         ruleset.debugInfo = debugInfo;
@@ -1520,7 +1528,7 @@ less.Parser = function Parser(env) {
                 }
             },
             rule: function (tryAnonymous) {
-                var name, value, c = input.charAt(i), important, merge, isVariable;
+                var name, value, startOfRule = i, c = input.charAt(startOfRule), important, merge, isVariable;
                 save();
 
                 if (c === '.' || c === '#' || c === '&') { return; }
@@ -1549,7 +1557,7 @@ less.Parser = function Parser(env) {
                     }
 
                     if (value && this.end()) {
-                        return new (tree.Rule)(name, value, important, merge, memo, env.currentFileInfo);
+                        return new (tree.Rule)(name, value, important, merge, startOfRule, env.currentFileInfo);
                     } else {
                         furthest = i;
                         restore();
@@ -1557,6 +1565,8 @@ less.Parser = function Parser(env) {
                             return this.rule(true);
                         }
                     }
+                } else {
+                    forget();
                 }
             },
             anonymousValue: function () {
@@ -1590,6 +1600,7 @@ less.Parser = function Parser(env) {
                 if (dir && (path = this.entities.quoted() || this.entities.url())) {
                     features = this.mediaFeatures();
                     if ($char(';')) {
+                        forget();
                         features = features && new(tree.Value)(features);
                         return new(tree.Import)(path, features, options, index, env.currentFileInfo);
                     }
@@ -1790,6 +1801,7 @@ less.Parser = function Parser(env) {
                 }
 
                 if (rules || (!hasBlock && value && $char(';'))) {
+                    forget();
                     return new(tree.Directive)(name, value, rules, index, env.currentFileInfo, 
                         env.dumpLineNumbers ? getDebugInfo(index, input, env) : null);
                 }
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index dc706a62..e6b646a4 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -19,3 +19,13 @@ header {
 html.lt-ie9 header {
   background: red;
 }
+.wrap-selector {
+  test: extra-wrap;
+}
+.wrap-selector .wrap-selector {
+  test: wrapped-twice;
+}
+.wrap-selector {
+  test-func: 90;
+  test-arithmetic: 18px;
+}
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 665fdfba..3829f681 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -45,4 +45,5 @@ header {
 
 .wrap-mixin({
   test-func: unit(90px);
+  test-arithmetic: unit((9+9), px);
 });

From ef3c63fb9ae920f1e969b707ba296ac6d930e579 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 12 Feb 2014 23:34:14 +0000
Subject: [PATCH 12/29] Test out some theoretical back tracking and fix bugs

---
 lib/less/parser.js | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index 8231bf83..46c74cfc 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -1138,6 +1138,8 @@ less.Parser = function Parser(env) {
                         expressions = [], argsSemiColon = [], argsComma = [],
                         isSemiColonSeperated, expressionContainsNamed, name, nameLoop, value, arg;
 
+                    save();
+
                     while (true) {
                         if (isCall) {
                             arg = parsers.blockRuleset() || parsers.expression();
@@ -1183,13 +1185,17 @@ less.Parser = function Parser(env) {
                                     }
                                     expressionContainsNamed = true;
                                 }
+
                                 // we do not support setting a ruleset as a default variable - it doesn't make sense
-                                // and to implement it we need backtracking with multiple saves
+                                // However if we do want to add it, there is nothing blocking it, just don't error
+                                // and remove isCall dependency below
                                 value = (isCall && parsers.blockRuleset()) || parsers.expression();
+
                                 if (!value) {
                                     if (isCall) {
                                         error("could not understand value for named argument");
                                     } else {
+                                        restore();
                                         returner.args = [];
                                         return returner;
                                     }
@@ -1238,6 +1244,7 @@ less.Parser = function Parser(env) {
                         }
                     }
 
+                    forget();
                     returner.args = isSemiColonSeperated ? argsSemiColon : argsComma;
                     return returner;
                 },
@@ -1302,6 +1309,8 @@ less.Parser = function Parser(env) {
                         } else {
                             restore();
                         }
+                    } else {
+                        forget();
                     }
                 }
             },
@@ -1529,10 +1538,11 @@ less.Parser = function Parser(env) {
             },
             rule: function (tryAnonymous) {
                 var name, value, startOfRule = i, c = input.charAt(startOfRule), important, merge, isVariable;
-                save();
 
                 if (c === '.' || c === '#' || c === '&') { return; }
 
+                save();
+
                 name = this.variable() || this.ruleProperty();
                 if (name) {
                     isVariable = typeof name === "string";
@@ -1557,6 +1567,7 @@ less.Parser = function Parser(env) {
                     }
 
                     if (value && this.end()) {
+                        forget();
                         return new (tree.Rule)(name, value, important, merge, startOfRule, env.currentFileInfo);
                     } else {
                         furthest = i;

From 15174c0860010be3969fed3008b2c79ce2cae8ad Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Wed, 12 Feb 2014 23:38:35 +0000
Subject: [PATCH 13/29] small approx 1% speed improvement

---
 lib/less/parser.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/less/parser.js b/lib/less/parser.js
index 46c74cfc..7e0c4a22 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -737,6 +737,9 @@ less.Parser = function Parser(env) {
                             break;
                         }
                     }
+                    if (peekChar('}')) {
+                        break;
+                    }
                 }
 
                 return root;

From e0692fa199fc6828f0136da05948cb2c0194b611 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Thu, 13 Feb 2014 20:36:34 +0000
Subject: [PATCH 14/29] add scope tests to the detached ruleset test-set

---
 test/css/detached-rulesets.css   | 13 +++++++++++++
 test/less/detached-rulesets.less |  9 +++++++++
 2 files changed, 22 insertions(+)

diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index e6b646a4..b98bf60b 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -1,12 +1,19 @@
 .wrap-selector {
   color: black;
+  one: 1px;
+  visible-one: visible;
+  visible-two: visible;
 }
 .wrap-selector {
   color: red;
+  visible-one: visible;
+  visible-two: visible;
 }
 .wrap-selector {
   color: black;
   background: white;
+  visible-one: visible;
+  visible-two: visible;
 }
 header {
   background: blue;
@@ -21,11 +28,17 @@ html.lt-ie9 header {
 }
 .wrap-selector {
   test: extra-wrap;
+  visible-one: visible;
+  visible-two: visible;
 }
 .wrap-selector .wrap-selector {
   test: wrapped-twice;
+  visible-one: visible;
+  visible-two: visible;
 }
 .wrap-selector {
   test-func: 90;
   test-arithmetic: 18px;
+  visible-one: visible;
+  visible-two: visible;
 }
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 3829f681..57c2cb43 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -3,14 +3,23 @@
      background: white;
   };
 
+@a: 1px;
 .wrap-mixin(@ruleset) {
+  @a: hidden and if you see this in the output its a bug;
+  @b: visible;
   .wrap-selector {
+      @c: visible;
       @ruleset();
+	  visible-one: @b;
+	  visible-two: @c;
     }
 };
 
 .wrap-mixin({
   color: black;
+  one: @a;
+  @b: hidden and if you see this in the output its a bug;
+  @c: hidden and if you see this in the output its a bug;
 });
 
 .wrap-mixin(@ruleset: {

From b46ca11286e3c4fb8eb351ff01725cc9c4223add Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Thu, 13 Feb 2014 21:42:32 +0000
Subject: [PATCH 15/29] error tests and test detached rulesets without a mixin
 call

---
 lib/less/tree/rule.js                    | 17 ++++++++++++++---
 test/css/detached-rulesets.css           |  3 +++
 test/less/detached-rulesets.less         |  7 +++++++
 test/less/errors/detached-ruleset-1.less |  6 ++++++
 test/less/errors/detached-ruleset-1.txt  |  4 ++++
 test/less/errors/detached-ruleset-2.less |  6 ++++++
 test/less/errors/detached-ruleset-2.txt  |  4 ++++
 test/less/errors/detached-ruleset-3.less |  4 ++++
 test/less/errors/detached-ruleset-3.txt  |  4 ++++
 test/less/errors/detached-ruleset-4.less |  5 +++++
 test/less/errors/detached-ruleset-4.txt  |  3 +++
 test/less/errors/detached-ruleset-5.less |  4 ++++
 test/less/errors/detached-ruleset-5.txt  |  3 +++
 test/less/errors/detached-ruleset-6.less |  5 +++++
 test/less/errors/detached-ruleset-6.txt  |  4 ++++
 15 files changed, 76 insertions(+), 3 deletions(-)
 create mode 100644 test/less/errors/detached-ruleset-1.less
 create mode 100644 test/less/errors/detached-ruleset-1.txt
 create mode 100644 test/less/errors/detached-ruleset-2.less
 create mode 100644 test/less/errors/detached-ruleset-2.txt
 create mode 100644 test/less/errors/detached-ruleset-3.less
 create mode 100644 test/less/errors/detached-ruleset-3.txt
 create mode 100644 test/less/errors/detached-ruleset-4.less
 create mode 100644 test/less/errors/detached-ruleset-4.txt
 create mode 100644 test/less/errors/detached-ruleset-5.less
 create mode 100644 test/less/errors/detached-ruleset-5.txt
 create mode 100644 test/less/errors/detached-ruleset-6.less
 create mode 100644 test/less/errors/detached-ruleset-6.txt

diff --git a/lib/less/tree/rule.js b/lib/less/tree/rule.js
index a2d14f2b..ac90049c 100644
--- a/lib/less/tree/rule.js
+++ b/lib/less/tree/rule.js
@@ -30,7 +30,7 @@ tree.Rule.prototype = {
     },
     toCSS: tree.toCSS,
     eval: function (env) {
-        var strictMathBypass = false, name = this.name;    
+        var strictMathBypass = false, name = this.name, evaldValue;
         if (typeof name !== "string") {
             // expand 'primitive' name directly to get
             // things faster (~10% for benchmark.less):
@@ -43,14 +43,25 @@ tree.Rule.prototype = {
             env.strictMath = true;
         }
         try {
+            evaldValue = this.value.eval(env);
+            
+            if (!this.variable && evaldValue.type === "Ruleset") {
+                console.log(this.index);
+                throw { message: "Rulesets cannot be evaluated on a property.",
+                        index: this.index, filename: this.currentFileInfo.filename };
+            }
+
             return new(tree.Rule)(name,
-                              this.value.eval(env),
+                              evaldValue,
                               this.important,
                               this.merge,
                               this.index, this.currentFileInfo, this.inline);
         }
         catch(e) {
-            e.index = e.index || this.index;
+            if (typeof e.index !== 'number') {
+                e.index = this.index;
+                e.filename = this.currentFileInfo.filename;
+            }
             throw e;
         }
         finally {
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index b98bf60b..d723a0c4 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -42,3 +42,6 @@ html.lt-ie9 header {
   visible-one: visible;
   visible-two: visible;
 }
+.without-mixins {
+  b: 1;
+}
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 57c2cb43..787cc19b 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -56,3 +56,10 @@ header {
   test-func: unit(90px);
   test-arithmetic: unit((9+9), px);
 });
+// without mixins
+@ruleset-2: {
+  b: 1;
+};
+.without-mixins {
+  @ruleset-2();
+}
diff --git a/test/less/errors/detached-ruleset-1.less b/test/less/errors/detached-ruleset-1.less
new file mode 100644
index 00000000..ac5b8db0
--- /dev/null
+++ b/test/less/errors/detached-ruleset-1.less
@@ -0,0 +1,6 @@
+@a: {
+  b: 1;
+};
+.a {
+  a: @a;
+}
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-1.txt b/test/less/errors/detached-ruleset-1.txt
new file mode 100644
index 00000000..7407741c
--- /dev/null
+++ b/test/less/errors/detached-ruleset-1.txt
@@ -0,0 +1,4 @@
+SyntaxError: Rulesets cannot be evaluated on a property. in {path}detached-ruleset-1.less on line 5, column 3:
+4 .a {
+5   a: @a;
+6 }
diff --git a/test/less/errors/detached-ruleset-2.less b/test/less/errors/detached-ruleset-2.less
new file mode 100644
index 00000000..51a7af6b
--- /dev/null
+++ b/test/less/errors/detached-ruleset-2.less
@@ -0,0 +1,6 @@
+@a: {
+  b: 1;
+};
+.a {
+  a: @a();
+}
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-2.txt b/test/less/errors/detached-ruleset-2.txt
new file mode 100644
index 00000000..f18e0935
--- /dev/null
+++ b/test/less/errors/detached-ruleset-2.txt
@@ -0,0 +1,4 @@
+ParseError: Unrecognised input in {path}detached-ruleset-2.less on line 5, column 3:
+4 .a {
+5   a: @a();
+6 }
diff --git a/test/less/errors/detached-ruleset-3.less b/test/less/errors/detached-ruleset-3.less
new file mode 100644
index 00000000..c50119d9
--- /dev/null
+++ b/test/less/errors/detached-ruleset-3.less
@@ -0,0 +1,4 @@
+@a: {
+  b: 1;
+};
+@a();
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-3.txt b/test/less/errors/detached-ruleset-3.txt
new file mode 100644
index 00000000..15d281fa
--- /dev/null
+++ b/test/less/errors/detached-ruleset-3.txt
@@ -0,0 +1,4 @@
+SyntaxError: properties must be inside selector blocks, they cannot be in the root. in {path}detached-ruleset-3.less on line 2, column 3:
+1 @a: {
+2   b: 1;
+3 };
diff --git a/test/less/errors/detached-ruleset-4.less b/test/less/errors/detached-ruleset-4.less
new file mode 100644
index 00000000..14ac314b
--- /dev/null
+++ b/test/less/errors/detached-ruleset-4.less
@@ -0,0 +1,5 @@
+.mixin-definition(@a: {
+  b: 1;
+}) {
+  @a();
+}
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-4.txt b/test/less/errors/detached-ruleset-4.txt
new file mode 100644
index 00000000..d6d6526d
--- /dev/null
+++ b/test/less/errors/detached-ruleset-4.txt
@@ -0,0 +1,3 @@
+ParseError: Unrecognised input in {path}detached-ruleset-4.less on line 1, column 18:
+1 .mixin-definition(@a: {
+2   b: 1;
diff --git a/test/less/errors/detached-ruleset-5.less b/test/less/errors/detached-ruleset-5.less
new file mode 100644
index 00000000..174ebf35
--- /dev/null
+++ b/test/less/errors/detached-ruleset-5.less
@@ -0,0 +1,4 @@
+.mixin-definition(@b) {
+  @a();
+}
+.mixin-definition({color: red;});
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-5.txt b/test/less/errors/detached-ruleset-5.txt
new file mode 100644
index 00000000..56189795
--- /dev/null
+++ b/test/less/errors/detached-ruleset-5.txt
@@ -0,0 +1,3 @@
+SyntaxError: variable @a is undefined in {path}detached-ruleset-5.less on line 4, column 1:
+3 }
+4 .mixin-definition({color: red;});
diff --git a/test/less/errors/detached-ruleset-6.less b/test/less/errors/detached-ruleset-6.less
new file mode 100644
index 00000000..121099f7
--- /dev/null
+++ b/test/less/errors/detached-ruleset-6.less
@@ -0,0 +1,5 @@
+.a {
+  b: {
+    color: red;
+  };
+}
\ No newline at end of file
diff --git a/test/less/errors/detached-ruleset-6.txt b/test/less/errors/detached-ruleset-6.txt
new file mode 100644
index 00000000..07840445
--- /dev/null
+++ b/test/less/errors/detached-ruleset-6.txt
@@ -0,0 +1,4 @@
+ParseError: Unrecognised input in {path}detached-ruleset-6.less on line 2, column 3:
+1 .a {
+2   b: {
+3     color: red;

From c730829d1d609f250b522775fa1745537f6b77a4 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Sun, 16 Feb 2014 17:50:51 +0000
Subject: [PATCH 16/29] Fix one issue with media queries and detached rulesets,
 one to go

---
 lib/less/tree/media.js           |  2 ++
 lib/less/tree/rule.js            |  3 +--
 test/css/detached-rulesets.css   | 17 +++++++++++++
 test/less/detached-rulesets.less | 41 ++++++++++++++++++++++++++++++--
 4 files changed, 59 insertions(+), 4 deletions(-)

diff --git a/lib/less/tree/media.js b/lib/less/tree/media.js
index c3b85107..4531cf4c 100644
--- a/lib/less/tree/media.js
+++ b/lib/less/tree/media.js
@@ -147,6 +147,8 @@ tree.Media.prototype = {
       }
     },
     bubbleSelectors: function (selectors) {
+      if (!selectors)
+        return;
       this.rules = [new(tree.Ruleset)(selectors.slice(0), [this.rules[0]])];
     }
 };
diff --git a/lib/less/tree/rule.js b/lib/less/tree/rule.js
index ac90049c..5567b076 100644
--- a/lib/less/tree/rule.js
+++ b/lib/less/tree/rule.js
@@ -2,7 +2,7 @@
 
 tree.Rule = function (name, value, important, merge, index, currentFileInfo, inline) {
     this.name = name;
-    this.value = (value instanceof tree.Value) ? value : new(tree.Value)([value]);
+    this.value = (value instanceof tree.Value || value instanceof tree.Ruleset) ? value : new(tree.Value)([value]);
     this.important = important ? ' ' + important.trim() : '';
     this.merge = merge;
     this.index = index;
@@ -46,7 +46,6 @@ tree.Rule.prototype = {
             evaldValue = this.value.eval(env);
             
             if (!this.variable && evaldValue.type === "Ruleset") {
-                console.log(this.index);
                 throw { message: "Rulesets cannot be evaluated on a property.",
                         index: this.index, filename: this.currentFileInfo.filename };
             }
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index d723a0c4..b9642d4e 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -45,3 +45,20 @@ html.lt-ie9 header {
 .without-mixins {
   b: 1;
 }
+@media (orientation: portrait) {
+  /*    .wrap-media-mixin({
+      @media tv {
+        .triple-wrapped-mq {
+          triple: true;
+        }
+      }
+    });*/
+}
+@media (orientation: portrait) and tv {
+  .my-selector {
+    background-color: black;
+  }
+}
+.a {
+  test: test;
+}
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 787cc19b..5af2a745 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -10,8 +10,8 @@
   .wrap-selector {
       @c: visible;
       @ruleset();
-	  visible-one: @b;
-	  visible-two: @c;
+      visible-one: @b;
+      visible-two: @c;
     }
 };
 
@@ -63,3 +63,40 @@ header {
 .without-mixins {
   @ruleset-2();
 }
+@my-ruleset: {
+    .my-selector {
+      @media tv {
+        background-color: black;
+      }
+    }
+  };
+@media (orientation:portrait) {
+    @my-ruleset();
+    // doesn't work yet
+/*    .wrap-media-mixin({
+      @media tv {
+        .triple-wrapped-mq {
+          triple: true;
+        }
+      }
+    });*/
+}
+.wrap-media-mixin(@ruleset) {
+  @media widescreen {
+    @media print {
+      @ruleset();
+    }
+    @ruleset();
+  }
+  @ruleset();
+}
+// unlocking mixins
+@my-mixins: {
+  .mixin() {
+    test: test;
+  }
+};
+@my-mixins();
+.a {
+  .mixin();
+}
\ No newline at end of file

From baba33ea6a1a4b9a42fa07870c14581a78e05559 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Mon, 17 Feb 2014 19:15:47 +0000
Subject: [PATCH 17/29] Fix some bugs with detached rulesets and media queries

---
 build/build.yml                   |  1 +
 lib/less/index.js                 |  1 +
 lib/less/parser.js                | 14 +++++++++++---
 lib/less/tree/detached-ruleset.js | 21 +++++++++++++++++++++
 lib/less/tree/rule.js             |  2 +-
 lib/less/tree/ruleset-call.js     |  3 ++-
 lib/less/tree/ruleset.js          |  3 +++
 test/css/detached-rulesets.css    | 25 ++++++++++++++++---------
 test/less/detached-rulesets.less  | 10 ++++++----
 9 files changed, 62 insertions(+), 18 deletions(-)
 create mode 100644 lib/less/tree/detached-ruleset.js

diff --git a/build/build.yml b/build/build.yml
index 68fa2607..b5a2234a 100644
--- a/build/build.yml
+++ b/build/build.yml
@@ -127,6 +127,7 @@ tree:
   - <%= build.lib %>/tree/color.js
   - <%= build.lib %>/tree/comment.js
   - <%= build.lib %>/tree/condition.js
+  - <%= build.lib %>/tree/detached-ruleset.js
   - <%= build.lib %>/tree/dimension.js
   - <%= build.lib %>/tree/directive.js
   - <%= build.lib %>/tree/element.js
diff --git a/lib/less/index.js b/lib/less/index.js
index b85a84f9..a18b8179 100644
--- a/lib/less/index.js
+++ b/lib/less/index.js
@@ -94,6 +94,7 @@ var less = {
 
 require('./tree/color');
 require('./tree/directive');
+require('./tree/detached-ruleset');
 require('./tree/operation');
 require('./tree/dimension');
 require('./tree/keyword');
diff --git a/lib/less/parser.js b/lib/less/parser.js
index 7e0c4a22..032381dc 100644
--- a/lib/less/parser.js
+++ b/lib/less/parser.js
@@ -1145,7 +1145,7 @@ less.Parser = function Parser(env) {
 
                     while (true) {
                         if (isCall) {
-                            arg = parsers.blockRuleset() || parsers.expression();
+                            arg = parsers.detachedRuleset() || parsers.expression();
                         } else {
                             parsers.comments();
                             if (input.charAt(i) === '.' && $re(/^\.{3}/)) {
@@ -1192,7 +1192,7 @@ less.Parser = function Parser(env) {
                                 // we do not support setting a ruleset as a default variable - it doesn't make sense
                                 // However if we do want to add it, there is nothing blocking it, just don't error
                                 // and remove isCall dependency below
-                                value = (isCall && parsers.blockRuleset()) || parsers.expression();
+                                value = (isCall && parsers.detachedRuleset()) || parsers.expression();
 
                                 if (!value) {
                                     if (isCall) {
@@ -1491,11 +1491,19 @@ less.Parser = function Parser(env) {
 
             blockRuleset: function() {
                 var block = this.block();
+
                 if (block) {
                     block = new tree.Ruleset(null, block);
                 }
                 return block;
             },
+            
+            detachedRuleset: function() {
+                var blockRuleset = this.blockRuleset();
+                if (blockRuleset) {
+                    return new tree.DetachedRuleset(blockRuleset);
+                }
+            },
 
             //
             // div, .class, body > p {...}
@@ -1551,7 +1559,7 @@ less.Parser = function Parser(env) {
                     isVariable = typeof name === "string";
                     
                     if (isVariable) {
-                        value = this.blockRuleset();
+                        value = this.detachedRuleset();
                     }
                     
                     if (!value) {
diff --git a/lib/less/tree/detached-ruleset.js b/lib/less/tree/detached-ruleset.js
new file mode 100644
index 00000000..87e76f26
--- /dev/null
+++ b/lib/less/tree/detached-ruleset.js
@@ -0,0 +1,21 @@
+(function (tree) {
+
+tree.DetachedRuleset = function (ruleset, frames) {
+    this.ruleset = ruleset;
+    this.frames = frames;
+};
+tree.DetachedRuleset.prototype = {
+    type: "DetachedRuleset",
+    accept: function (visitor) {
+        this.ruleset = visitor.visit(this.ruleset);
+    },
+    eval: function (env) {
+        // TODO - handle mixin definition like this
+        var frames = this.frames || env.frames.slice(0);
+        return new tree.DetachedRuleset(this.ruleset, frames);
+    },
+    callEval: function (env) {
+        return this.ruleset.eval(new(tree.evalEnv)(env, this.frames.concat(env.frames)));
+    }
+};
+})(require('../tree'));
diff --git a/lib/less/tree/rule.js b/lib/less/tree/rule.js
index 5567b076..4e1ccde6 100644
--- a/lib/less/tree/rule.js
+++ b/lib/less/tree/rule.js
@@ -45,7 +45,7 @@ tree.Rule.prototype = {
         try {
             evaldValue = this.value.eval(env);
             
-            if (!this.variable && evaldValue.type === "Ruleset") {
+            if (!this.variable && evaldValue.type === "DetachedRuleset") {
                 throw { message: "Rulesets cannot be evaluated on a property.",
                         index: this.index, filename: this.currentFileInfo.filename };
             }
diff --git a/lib/less/tree/ruleset-call.js b/lib/less/tree/ruleset-call.js
index ec9e98d2..a543c55e 100644
--- a/lib/less/tree/ruleset-call.js
+++ b/lib/less/tree/ruleset-call.js
@@ -8,7 +8,8 @@ tree.RulesetCall.prototype = {
     accept: function (visitor) {
     },
     eval: function (env) {
-        return new(tree.Variable)(this.variable).eval(env);
+        var detachedRuleset = new(tree.Variable)(this.variable).eval(env);
+        return detachedRuleset.callEval(env);
     }
 };
 
diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index 15cc80d9..3ec0706d 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -358,6 +358,9 @@ tree.Ruleset.prototype = {
     toCSS: tree.toCSS,
 
     markReferenced: function () {
+        if (!this.selectors) {
+            return;
+        }
         for (var s = 0; s < this.selectors.length; s++) {
             this.selectors[s].markReferenced();
         }
diff --git a/test/css/detached-rulesets.css b/test/css/detached-rulesets.css
index b9642d4e..300c08d0 100644
--- a/test/css/detached-rulesets.css
+++ b/test/css/detached-rulesets.css
@@ -1,6 +1,7 @@
 .wrap-selector {
   color: black;
   one: 1px;
+  four: magic-frame;
   visible-one: visible;
   visible-two: visible;
 }
@@ -45,20 +46,26 @@ html.lt-ie9 header {
 .without-mixins {
   b: 1;
 }
-@media (orientation: portrait) {
-  /*    .wrap-media-mixin({
-      @media tv {
-        .triple-wrapped-mq {
-          triple: true;
-        }
-      }
-    });*/
-}
 @media (orientation: portrait) and tv {
   .my-selector {
     background-color: black;
   }
 }
+@media (orientation: portrait) and widescreen and print and tv {
+  .triple-wrapped-mq {
+    triple: true;
+  }
+}
+@media (orientation: portrait) and widescreen and tv {
+  .triple-wrapped-mq {
+    triple: true;
+  }
+}
+@media (orientation: portrait) and tv {
+  .triple-wrapped-mq {
+    triple: true;
+  }
+}
 .a {
   test: test;
 }
diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 5af2a745..7e124117 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -7,6 +7,7 @@
 .wrap-mixin(@ruleset) {
   @a: hidden and if you see this in the output its a bug;
   @b: visible;
+  @d: magic-frame; // same behaviour as mixin calls - falls back to this frame
   .wrap-selector {
       @c: visible;
       @ruleset();
@@ -20,6 +21,7 @@
   one: @a;
   @b: hidden and if you see this in the output its a bug;
   @c: hidden and if you see this in the output its a bug;
+  four: @d;
 });
 
 .wrap-mixin(@ruleset: {
@@ -72,14 +74,13 @@ header {
   };
 @media (orientation:portrait) {
     @my-ruleset();
-    // doesn't work yet
-/*    .wrap-media-mixin({
+    .wrap-media-mixin({
       @media tv {
         .triple-wrapped-mq {
           triple: true;
         }
       }
-    });*/
+    });
 }
 .wrap-media-mixin(@ruleset) {
   @media widescreen {
@@ -99,4 +100,5 @@ header {
 @my-mixins();
 .a {
   .mixin();
-}
\ No newline at end of file
+}
+// Same fallback frame behaviour as mixin calls
\ No newline at end of file

From 88b44dfc43d9dd9e11a8993be8635ed85d359715 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Mon, 17 Feb 2014 19:50:43 +0000
Subject: [PATCH 18/29] make mixin definitions have similar coding style to
 detached rulesets for grabbing frames

---
 lib/less/tree/detached-ruleset.js |  3 +--
 lib/less/tree/mixin.js            | 13 ++++++++-----
 lib/less/tree/ruleset.js          |  6 +++---
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/lib/less/tree/detached-ruleset.js b/lib/less/tree/detached-ruleset.js
index 87e76f26..0a5512aa 100644
--- a/lib/less/tree/detached-ruleset.js
+++ b/lib/less/tree/detached-ruleset.js
@@ -10,12 +10,11 @@ tree.DetachedRuleset.prototype = {
         this.ruleset = visitor.visit(this.ruleset);
     },
     eval: function (env) {
-        // TODO - handle mixin definition like this
         var frames = this.frames || env.frames.slice(0);
         return new tree.DetachedRuleset(this.ruleset, frames);
     },
     callEval: function (env) {
-        return this.ruleset.eval(new(tree.evalEnv)(env, this.frames.concat(env.frames)));
+        return this.ruleset.eval(this.frames ? new(tree.evalEnv)(env, this.frames.concat(env.frames)) : env);
     }
 };
 })(require('../tree'));
diff --git a/lib/less/tree/mixin.js b/lib/less/tree/mixin.js
index 1d903e87..506561ba 100644
--- a/lib/less/tree/mixin.js
+++ b/lib/less/tree/mixin.js
@@ -103,7 +103,7 @@ tree.mixin.Call.prototype = {
                                 mixin.originalRuleset = mixins[m].originalRuleset || mixins[m];
                             }
                             Array.prototype.push.apply(
-                                  rules, mixin.eval(env, args, this.important).rules);
+                                  rules, mixin.evalCall(env, args, this.important).rules);
                         } catch (e) {
                             throw { message: e.message, index: this.index, filename: this.currentFileInfo.filename, stack: e.stack };
                         }
@@ -150,7 +150,7 @@ tree.mixin.Call.prototype = {
     }
 };
 
-tree.mixin.Definition = function (name, params, rules, condition, variadic) {
+tree.mixin.Definition = function (name, params, rules, condition, variadic, frames) {
     this.name = name;
     this.selectors = [new(tree.Selector)([new(tree.Element)(null, name, this.index, this.currentFileInfo)])];
     this.params = params;
@@ -164,7 +164,7 @@ tree.mixin.Definition = function (name, params, rules, condition, variadic) {
         else                                 { return count; }
     }, 0);
     this.parent = tree.Ruleset.prototype;
-    this.frames = [];
+    this.frames = frames;
 };
 tree.mixin.Definition.prototype = {
     type: "MixinDefinition",
@@ -258,9 +258,12 @@ tree.mixin.Definition.prototype = {
 
         return frame;
     },
-    eval: function (env, args, important) {
+    eval: function (env) {
+        return new tree.mixin.Definition(this.name, this.params, this.rules, this.condition, this.variadic, this.frames || env.frames.slice(0));
+    },
+    evalCall: function (env, args, important) {
         var _arguments = [],
-            mixinFrames = this.frames.concat(env.frames),
+            mixinFrames = this.frames ? this.frames.concat(env.frames) : env.frames,
             frame = this.evalParams(env, new(tree.evalEnv)(env, mixinFrames), args, _arguments),
             rules, ruleset;
 
diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index 3ec0706d..7571b0e7 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -66,8 +66,8 @@ tree.Ruleset.prototype = {
         // so they can be evaluated like closures when the time comes.
         var rsRules = ruleset.rules, rsRuleCnt = rsRules ? rsRules.length : 0;
         for (i = 0; i < rsRuleCnt; i++) {
-            if (rsRules[i] instanceof tree.mixin.Definition) {
-                rsRules[i].frames = envFrames.slice(0);
+            if (rsRules[i] instanceof tree.mixin.Definition || rsRules[i] instanceof tree.DetachedRuleset) {
+                rsRules[i] = rsRules[i].eval(env);
             }
         }
 
@@ -109,7 +109,7 @@ tree.Ruleset.prototype = {
         // Evaluate everything else
         for (i = 0; i < rsRules.length; i++) {
             rule = rsRules[i];
-            if (! (rule instanceof tree.mixin.Definition)) {
+            if (! (rule instanceof tree.mixin.Definition || rule instanceof tree.DetachedRuleset)) {
                 rsRules[i] = rule = rule.eval ? rule.eval(env) : rule;
                 // for rulesets, check if it is a css guard and can be removed
                 if (rule instanceof tree.Ruleset && rule.selectors && rule.selectors.length === 1) {

From 42aff6f35c8890039c8dee6d65dfd04c94336904 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Mon, 17 Feb 2014 19:53:35 +0000
Subject: [PATCH 19/29] remove bad comment

---
 test/less/detached-rulesets.less | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/less/detached-rulesets.less b/test/less/detached-rulesets.less
index 7e124117..6a98d890 100644
--- a/test/less/detached-rulesets.less
+++ b/test/less/detached-rulesets.less
@@ -100,5 +100,4 @@ header {
 @my-mixins();
 .a {
   .mixin();
-}
-// Same fallback frame behaviour as mixin calls
\ No newline at end of file
+}
\ No newline at end of file

From d31e2d57407c483d6a3270f7d0fe4ae9a9d4099c Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Mon, 17 Feb 2014 20:25:18 +0000
Subject: [PATCH 20/29] upgrade dependencies

---
 bin/lessc    |  6 +++---
 package.json | 20 ++++++++++----------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/bin/lessc b/bin/lessc
index 9c27f5f0..8b2fc2bd 100755
--- a/bin/lessc
+++ b/bin/lessc
@@ -231,13 +231,13 @@ args = args.filter(function (arg) {
                 case "--advanced":
                     cleancssOptions.noAdvanced = false;
                     break;
-                case "--selectors-merge-mode":
-                    cleancssOptions.selectorsMergeMode = cleanOptionArgs[1];
+                case "--compatability":
+                    cleancssOptions.compatability = cleanOptionArgs[1];
                     break;
                 default:
                     console.log("unrecognised clean-css option '" + cleanOptionArgs[0] + "'");
                     console.log("we support only arguments that make sense for less, '--keep-line-breaks', '-b'");
-                    console.log("'--s0', '--s1', '--advanced', '--skip-advanced', '--selectors-merge-mode'");
+                    console.log("'--s0', '--s1', '--advanced', '--skip-advanced', '--compatability'");
                     continueProcessing = false;
                     currentErrorcode = 1;
                     break;
diff --git a/package.json b/package.json
index 45b0dd9c..d79d9f9a 100644
--- a/package.json
+++ b/package.json
@@ -41,24 +41,24 @@
   },
   "optionalDependencies": {
     "mime": "1.2.x",
-    "request": ">=2.12.0",
+    "request": ">=2.33.0",
     "mkdirp": "~0.3.5",
-    "clean-css": "2.0.x",
+    "clean-css": "2.1.x",
     "source-map": "0.1.x"
   },
   "devDependencies": {
     "diff": "~1.0",
-    "grunt": "~0.4.1",
+    "grunt": "~0.4.2",
     "grunt-contrib-clean": "~0.5.0",
     "grunt-contrib-concat": "~0.3.0",
-    "grunt-contrib-connect": "~0.3.0",
+    "grunt-contrib-connect": "~0.6.0",
     "grunt-contrib-jasmine": "~0.5.2",
-    "grunt-contrib-jshint": "~0.7.2",
-    "grunt-contrib-uglify": "~0.2.7",
-    "grunt-shell": "~0.3.1",
-    "http-server": "~0.5.5",
-    "matchdep": "~0.1.2",
-    "time-grunt": "~0.1.1"
+    "grunt-contrib-jshint": "~0.8.0",
+    "grunt-contrib-uglify": "~0.3.2",
+    "grunt-shell": "~0.6.4",
+    "http-server": "~0.6.1",
+    "matchdep": "~0.3.0",
+    "time-grunt": "~0.2.9"
  },
   "keywords": [
     "compile less",

From f3b9713ba30572a29fbed0d51345343a12dcb87b Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Tue, 18 Feb 2014 07:21:22 +0000
Subject: [PATCH 21/29] correct spelling of compatibility option

---
 bin/lessc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/bin/lessc b/bin/lessc
index 8b2fc2bd..b36c062a 100755
--- a/bin/lessc
+++ b/bin/lessc
@@ -231,13 +231,13 @@ args = args.filter(function (arg) {
                 case "--advanced":
                     cleancssOptions.noAdvanced = false;
                     break;
-                case "--compatability":
-                    cleancssOptions.compatability = cleanOptionArgs[1];
+                case "--compatibility":
+                    cleancssOptions.compatibility = cleanOptionArgs[1];
                     break;
                 default:
                     console.log("unrecognised clean-css option '" + cleanOptionArgs[0] + "'");
                     console.log("we support only arguments that make sense for less, '--keep-line-breaks', '-b'");
-                    console.log("'--s0', '--s1', '--advanced', '--skip-advanced', '--compatability'");
+                    console.log("'--s0', '--s1', '--advanced', '--skip-advanced', '--compatibility'");
                     continueProcessing = false;
                     currentErrorcode = 1;
                     break;

From d3c0b204c7c2d7071474a4c1b3a4dc5560b3be35 Mon Sep 17 00:00:00 2001
From: seven-phases-max <seven.phases.max@gmail.com>
Date: Tue, 18 Feb 2014 15:22:14 +0400
Subject: [PATCH 22/29] minor `replace` func improvement: preserve quote char
 and escaped flag.

---
 lib/less/functions.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index 413ae98e..552f052c 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -222,8 +222,7 @@ tree.functions = {
         var str = subject.value;
 
         str = str.replace(new RegExp(pattern.value, flags ? flags.value : ""), replacement.value);
-
-        return new(tree.Quoted)('"' + str + '"', str);
+        return new(tree.Quoted)(subject.quote || '', str, subject.escaped);
     },
     '%': function (quoted /* arg, arg, ...*/) {
         var args = Array.prototype.slice.call(arguments, 1),

From 768a5cbc8459d82c4cc725719024900b6b264850 Mon Sep 17 00:00:00 2001
From: seven-phases-max <seven.phases.max@gmail.com>
Date: Tue, 18 Feb 2014 18:56:46 +0400
Subject: [PATCH 23/29] minor `%` func improvement: preserve quote char and
 escaped flag, updated tests.

---
 lib/less/functions.js    | 18 +++++++++---------
 test/css/functions.css   |  5 +++++
 test/less/functions.less |  7 ++++++-
 3 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/lib/less/functions.js b/lib/less/functions.js
index 552f052c..2c269a98 100644
--- a/lib/less/functions.js
+++ b/lib/less/functions.js
@@ -218,25 +218,25 @@ tree.functions = {
     escape: function (str) {
         return new(tree.Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
     },
-    replace: function (subject, pattern, replacement, flags) {
-        var str = subject.value;
+    replace: function (string, pattern, replacement, flags) {
+        var result = string.value;
 
-        str = str.replace(new RegExp(pattern.value, flags ? flags.value : ""), replacement.value);
-        return new(tree.Quoted)(subject.quote || '', str, subject.escaped);
+        result = result.replace(new RegExp(pattern.value, flags ? flags.value : ''), replacement.value);
+        return new(tree.Quoted)(string.quote || '', result, string.escaped);
     },
-    '%': function (quoted /* arg, arg, ...*/) {
+    '%': function (string /* arg, arg, ...*/) {
         var args = Array.prototype.slice.call(arguments, 1),
-            str = quoted.value;
+            result = string.value;
 
         for (var i = 0; i < args.length; i++) {
             /*jshint loopfunc:true */
-            str = str.replace(/%[sda]/i, function(token) {
+            result = result.replace(/%[sda]/i, function(token) {
                 var value = token.match(/s/i) ? args[i].value : args[i].toCSS();
                 return token.match(/[A-Z]$/) ? encodeURIComponent(value) : value;
             });
         }
-        str = str.replace(/%%/g, '%');
-        return new(tree.Quoted)('"' + str + '"', str);
+        result = result.replace(/%%/g, '%');
+        return new(tree.Quoted)(string.quote || '', result, string.escaped);
     },
     unit: function (val, unit) {
         if(!(val instanceof tree.Dimension)) {
diff --git a/test/css/functions.css b/test/css/functions.css
index 277bb1bd..17509c18 100644
--- a/test/css/functions.css
+++ b/test/css/functions.css
@@ -48,10 +48,15 @@
   replace: "Hello, World!";
   replace-captured: "This is a new string.";
   replace-with-flags: "2 + 2 = 4";
+  replace-single-quoted: 'foo-2';
+  replace-escaped-string: bar-2;
+  replace-keyword: baz-2;
   format: "rgb(32, 128, 64)";
   format-string: "hello world";
   format-multiple: "hello earth 2";
   format-url-encode: "red is %23ff0000";
+  format-single-quoted: 'hello single world';
+  format-escaped-string: hello escaped world;
   eformat: rgb(32, 128, 64);
   unitless: 12;
   unit: 14em;
diff --git a/test/less/functions.less b/test/less/functions.less
index ba9fe07c..87686bee 100644
--- a/test/less/functions.less
+++ b/test/less/functions.less
@@ -52,10 +52,15 @@
   replace: replace("Hello, Mars.", "Mars\.", "World!");
   replace-captured: replace("This is a string.", "(string)\.$", "new $1.");
   replace-with-flags: replace("One + one = 4", "one", "2", "gi");
+  replace-single-quoted: replace('foo-1', "1", "2");
+  replace-escaped-string: replace(~"bar-1", "1", "2");
+  replace-keyword: replace(baz-1, "1", "2");
   format: %("rgb(%d, %d, %d)", @r, 128, 64);
   format-string: %("hello %s", "world");
   format-multiple: %("hello %s %d", "earth", 2);
-  format-url-encode: %('red is %A', #ff0000);
+  format-url-encode: %("red is %A", #ff0000);
+  format-single-quoted: %('hello %s', "single world");
+  format-escaped-string: %(~"hello %s", "escaped world");
   eformat: e(%("rgb(%d, %d, %d)", @r, 128, 64));
   
   unitless: unit(12px);

From 3d338ceff177926001216bed9c9a9254efbc09ff Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Thu, 20 Feb 2014 07:15:30 +0000
Subject: [PATCH 24/29] Update README.md

---
 build/README.md | 304 +-----------------------------------------------
 1 file changed, 2 insertions(+), 302 deletions(-)

diff --git a/build/README.md b/build/README.md
index 2ac5171a..26655812 100644
--- a/build/README.md
+++ b/build/README.md
@@ -14,265 +14,16 @@ Options for adding Less.js to your project:
 * [Download the latest release][download]
 * Clone the repo: `git clone git://github.com/less/less.js.git`
 
-
-
-## Feature Highlights
-LESS extends CSS with dynamic features such as:
-
-* [nesting](#nesting)
-* [variables](#variables)
-* [operations](#operations)
-* [mixins](#mixins)
-* [extend](#extend) (selector inheritance)
-
-To learn about the many other features Less.js has to offer please visit [http://lesscss.org](http://lesscss.org) and [the Less.js wiki][wiki]
-
-
-### Examples
-#### nesting
-Take advantage of nesting to make code more readable and maintainable. This:
-
-```less
-.nav > li > a {
-  border: 1px solid #f5f5f5;
-  &:hover {
-    border-color: #ddd;
-  }
-}
-```
-
-renders to:
-
-```css
-.nav > li > a {
-  border: 1px solid #f5f5f5;
-}
-.nav > li > a:hover {
-  border-color: #ddd;
-}
-```
-
-
-#### variables
-Updated commonly used values from a single location.
-
-```less
-// Variables ("inline" comments like this can be used)
-@link-color:  #428bca; // appears as "sea blue"
-
-/* Or "block comments" that span
-   multiple lines, like this */
-a {
-  color: @link-color; // use the variable in styles
-}
-```
-
-Variables can also be used in `@import` statements, URLs, selector names, and more.
-
-
-
-#### operations
-Continuing with the same example above, we can use our variables even easier to maintain with _operations_, which enables the use of addition, subraction, multiplication and division in your styles:
-
-```less
-// Variables
-@link-color:        #428bca;
-@link-color-hover:  darken(@link-color, 10%);
-
-// Styles
-a {
-  color: @link-color;
-}
-a:hover {
-  color: @link-color-hover;
-}
-```
-renders to:
-
-```css
-a {
-  color: #428bca;
-}
-a:hover {
-  color: #3071a9;
-}
-```
-
-#### mixins
-##### "implicit" mixins
-Mixins enable you to apply the styles of one selector inside another selector like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-
-// Any "regular" class...
-.link {
-  color: @link-color;
-}
-a {
-  font-weight: bold;
-  .link; // ...can be used as an "implicit" mixin
-}
-```
-
-renders to:
-
-```css
-.link {
-  color: #428bca;
-}
-a {
-  font-weight: bold;
-  color: #428bca;
-}
-```
-
-So any selector can be an "implicit mixin". We'll show you a DRYer way to do this below.
-
-
-
-##### parametric mixins
-Mixins can also accept parameters:
-
-```less
-// Transition mixin
-.transition(@transition) {
-  -webkit-transition: @transition;
-     -moz-transition: @transition;
-       -o-transition: @transition;
-          transition: @transition;
-}
-```
-
-used like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-@link-color-hover:  darken(@link-color, 10%);
-
-//Transition mixin would be anywhere here
-
-a {
-  font-weight: bold;
-  color: @link-color;
-  .transition(color .2s ease-in-out);
-  // Hover state
-  &:hover {
-    color: @link-color-hover;
-  }
-}
-```
-
-renders to:
-
-```css
-a {
-  font-weight: bold;
-  color: #428bca;
-  -webkit-transition: color 0.2s ease-in-out;
-     -moz-transition: color 0.2s ease-in-out;
-       -o-transition: color 0.2s ease-in-out;
-          transition: color 0.2s ease-in-out;
-}
-a:hover {
-  color: #3071a9;
-}
-```
-
-
-#### extend
-The `extend` feature can be thought of as the _inverse_ of mixins. It accomplishes the goal of "borrowing styles", but rather than copying all the rules of _Selector A_ over to _Selector B_, `extend` copies the name of the _inheriting selector_ (_Selector B_) over to the _extending selector_ (_Selector A_). So continuing with the example used for [mixins](#mixins) above, extend works like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-
-.link {
-  color: @link-color;
-}
-a:extend(.link) {
-  font-weight: bold;
-}
-// Can also be written as
-a {
-  &:extend(.link);
-  font-weight: bold;
-}
-```
-
-renders to:
-
-```css
-.link, a {
-  color: #428bca;
-}
-a {
-  font-weight: bold;
-}
-```
-
-## Usage
-
-### Compiling and Parsing
-Invoke the compiler from node:
-
-```javascript
-var less = require('less');
-
-less.render('.class { width: (1 + 1) }', function (e, css) {
-    console.log(css);
-});
-```
-
-Outputs:
-
-```css
-.class {
-  width: 2;
-}
-```
-
-You may also manually invoke the parser and compiler:
-
-```javascript
-var parser = new(less.Parser);
-
-parser.parse('.class { width: (1 + 1) }', function (err, tree) {
-    if (err) { return console.error(err) }
-    console.log(tree.toCSS());
-});
-```
-
-
-### Configuration
-You may also pass options to the compiler:
-
-```javascript
-var parser = new(less.Parser)({
-    paths: ['.', './src/less'], // Specify search paths for @import directives
-    filename: 'style.less'      // Specify a filename, for better error messages
-});
-
-parser.parse('.class { width: (1 + 1) }', function (e, tree) {
-    tree.toCSS({ compress: true }); // Minify CSS output
-});
-```
-
 ## More information
 
-For general information on the language, configuration options or usage visit [lesscss.org](http://lesscss.org) or [the less wiki][wiki].
+For general information on the language, configuration options or usage visit [lesscss.org](http://lesscss.org).
 
 Here are other resources for using Less.js:
 
 * [stackoverflow.com][so] is a great place to get answers about Less.
-* [node.js tools](https://github.com/less/less.js/wiki/Converting-LESS-to-CSS) for converting Less to CSS
-* [GUI compilers for Less](https://github.com/less/less.js/wiki/GUI-compilers-that-use-LESS.js)
 * [Less.js Issues][issues] for reporting bugs
 
 
-
 ## Contributing
 Please read [CONTRIBUTING.md](./CONTRIBUTING.md). Add unit tests for any new or changed functionality. Lint and test your code using [Grunt](http://gruntjs.com/).
 
@@ -284,57 +35,7 @@ Please report documentation issues in [the documentation project](https://github
 
 ### Development
 
-#### Install Less.js
-
-Start by either [downloading this project][download] manually, or in the command line:
-
-```shell
-git clone https://github.com/less/less.js.git "less"
-```
-and then `cd less`.
-
-
-#### Install dependencies
-
-To install all the dependencies for less development, run:
-
-```shell
-npm install
-```
-
-If you haven't run grunt before, install grunt-cli globally so you can just run `grunt`
-
-```shell
-npm install grunt-cli -g
-```
-
-You should now be able to build Less.js, run tests, benchmarking, and other tasks listed in the Gruntfile.
-
-## Using Less.js Grunt
-
-Tests, benchmarking and building is done using Grunt `<%= pkg.devDependencies.grunt %>`. If you haven't used [Grunt](http://gruntjs.com/) before, be sure to check out the [Getting Started](http://gruntjs.com/getting-started) guide, as it explains how to install and use Grunt plugins, which are necessary for development with Less.js.
-
-The Less.js [Gruntfile](Gruntfile.js) is configured with the following "convenience tasks" :
-
-#### test - `grunt`
-Runs jshint, nodeunit and headless jasmine tests using [phantomjs](http://code.google.com/p/phantomjs/). You must have phantomjs installed for the jasmine tests to run.
-
-#### test - `grunt benchmark`
-Runs the benchmark suite.
-
-#### build for testing browser - 'grunt browser'
-This builds less.js and puts it in 'test/browser/less.js'
-
-#### build - `grunt stable | grunt beta | grunt alpha`
-Builds Less.js from from the `/lib/less` source files. This is done by the developer releasing a new release, do not do this if you are creating a pull request.
-
-#### readme - `grunt readme`
-Build the README file from [a template](build/README.md) to ensure that metadata is up-to-date and (more likely to be) correct.
-
-Please review the [Gruntfile](Gruntfile.js) to become acquainted with the other available tasks.
-
-**Please note** that if you have any issues installing dependencies or running any of the Gruntfile commands, please make sure to uninstall any previous versions, both in the local node_modules directory, and clear your global npm cache, and then try running `npm install` again. After that if you still have issues, please let us know about it so we can help.
-
+Read [Developing Less](http://lesscss.org/usage/#developing-less).
 
 ## Release History
 See the [changelog](CHANGELOG.md)
@@ -347,5 +48,4 @@ Licensed under the [Apache License](LICENSE).
 
 [so]: http://stackoverflow.com/questions/tagged/twitter-bootstrap+less "StackOverflow.com"
 [issues]: https://github.com/less/less.js/issues "GitHub Issues for Less.js"
-[wiki]: https://github.com/less/less.js/wiki "The official wiki for Less.js"
 [download]: https://github.com/less/less.js/zipball/master "Download Less.js"

From 6d5473e9884c91eee6eae43a7aa8d49460c6d5ab Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Thu, 20 Feb 2014 07:16:16 +0000
Subject: [PATCH 25/29] update readme

---
 README.md | 304 +-----------------------------------------------------
 1 file changed, 2 insertions(+), 302 deletions(-)

diff --git a/README.md b/README.md
index c7d3ec68..0697a246 100644
--- a/README.md
+++ b/README.md
@@ -14,265 +14,16 @@ Options for adding Less.js to your project:
 * [Download the latest release][download]
 * Clone the repo: `git clone git://github.com/less/less.js.git`
 
-
-
-## Feature Highlights
-LESS extends CSS with dynamic features such as:
-
-* [nesting](#nesting)
-* [variables](#variables)
-* [operations](#operations)
-* [mixins](#mixins)
-* [extend](#extend) (selector inheritance)
-
-To learn about the many other features Less.js has to offer please visit [http://lesscss.org](http://lesscss.org) and [the Less.js wiki][wiki]
-
-
-### Examples
-#### nesting
-Take advantage of nesting to make code more readable and maintainable. This:
-
-```less
-.nav > li > a {
-  border: 1px solid #f5f5f5;
-  &:hover {
-    border-color: #ddd;
-  }
-}
-```
-
-renders to:
-
-```css
-.nav > li > a {
-  border: 1px solid #f5f5f5;
-}
-.nav > li > a:hover {
-  border-color: #ddd;
-}
-```
-
-
-#### variables
-Updated commonly used values from a single location.
-
-```less
-// Variables ("inline" comments like this can be used)
-@link-color:  #428bca; // appears as "sea blue"
-
-/* Or "block comments" that span
-   multiple lines, like this */
-a {
-  color: @link-color; // use the variable in styles
-}
-```
-
-Variables can also be used in `@import` statements, URLs, selector names, and more.
-
-
-
-#### operations
-Continuing with the same example above, we can use our variables even easier to maintain with _operations_, which enables the use of addition, subraction, multiplication and division in your styles:
-
-```less
-// Variables
-@link-color:        #428bca;
-@link-color-hover:  darken(@link-color, 10%);
-
-// Styles
-a {
-  color: @link-color;
-}
-a:hover {
-  color: @link-color-hover;
-}
-```
-renders to:
-
-```css
-a {
-  color: #428bca;
-}
-a:hover {
-  color: #3071a9;
-}
-```
-
-#### mixins
-##### "implicit" mixins
-Mixins enable you to apply the styles of one selector inside another selector like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-
-// Any "regular" class...
-.link {
-  color: @link-color;
-}
-a {
-  font-weight: bold;
-  .link; // ...can be used as an "implicit" mixin
-}
-```
-
-renders to:
-
-```css
-.link {
-  color: #428bca;
-}
-a {
-  font-weight: bold;
-  color: #428bca;
-}
-```
-
-So any selector can be an "implicit mixin". We'll show you a DRYer way to do this below.
-
-
-
-##### parametric mixins
-Mixins can also accept parameters:
-
-```less
-// Transition mixin
-.transition(@transition) {
-  -webkit-transition: @transition;
-     -moz-transition: @transition;
-       -o-transition: @transition;
-          transition: @transition;
-}
-```
-
-used like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-@link-color-hover:  darken(@link-color, 10%);
-
-//Transition mixin would be anywhere here
-
-a {
-  font-weight: bold;
-  color: @link-color;
-  .transition(color .2s ease-in-out);
-  // Hover state
-  &:hover {
-    color: @link-color-hover;
-  }
-}
-```
-
-renders to:
-
-```css
-a {
-  font-weight: bold;
-  color: #428bca;
-  -webkit-transition: color 0.2s ease-in-out;
-     -moz-transition: color 0.2s ease-in-out;
-       -o-transition: color 0.2s ease-in-out;
-          transition: color 0.2s ease-in-out;
-}
-a:hover {
-  color: #3071a9;
-}
-```
-
-
-#### extend
-The `extend` feature can be thought of as the _inverse_ of mixins. It accomplishes the goal of "borrowing styles", but rather than copying all the rules of _Selector A_ over to _Selector B_, `extend` copies the name of the _inheriting selector_ (_Selector B_) over to the _extending selector_ (_Selector A_). So continuing with the example used for [mixins](#mixins) above, extend works like this:
-
-```less
-// Variables
-@link-color:        #428bca;
-
-.link {
-  color: @link-color;
-}
-a:extend(.link) {
-  font-weight: bold;
-}
-// Can also be written as
-a {
-  &:extend(.link);
-  font-weight: bold;
-}
-```
-
-renders to:
-
-```css
-.link, a {
-  color: #428bca;
-}
-a {
-  font-weight: bold;
-}
-```
-
-## Usage
-
-### Compiling and Parsing
-Invoke the compiler from node:
-
-```javascript
-var less = require('less');
-
-less.render('.class { width: (1 + 1) }', function (e, css) {
-    console.log(css);
-});
-```
-
-Outputs:
-
-```css
-.class {
-  width: 2;
-}
-```
-
-You may also manually invoke the parser and compiler:
-
-```javascript
-var parser = new(less.Parser);
-
-parser.parse('.class { width: (1 + 1) }', function (err, tree) {
-    if (err) { return console.error(err) }
-    console.log(tree.toCSS());
-});
-```
-
-
-### Configuration
-You may also pass options to the compiler:
-
-```javascript
-var parser = new(less.Parser)({
-    paths: ['.', './src/less'], // Specify search paths for @import directives
-    filename: 'style.less'      // Specify a filename, for better error messages
-});
-
-parser.parse('.class { width: (1 + 1) }', function (e, tree) {
-    tree.toCSS({ compress: true }); // Minify CSS output
-});
-```
-
 ## More information
 
-For general information on the language, configuration options or usage visit [lesscss.org](http://lesscss.org) or [the less wiki][wiki].
+For general information on the language, configuration options or usage visit [lesscss.org](http://lesscss.org).
 
 Here are other resources for using Less.js:
 
 * [stackoverflow.com][so] is a great place to get answers about Less.
-* [node.js tools](https://github.com/less/less.js/wiki/Converting-LESS-to-CSS) for converting Less to CSS
-* [GUI compilers for Less](https://github.com/less/less.js/wiki/GUI-compilers-that-use-LESS.js)
 * [Less.js Issues][issues] for reporting bugs
 
 
-
 ## Contributing
 Please read [CONTRIBUTING.md](./CONTRIBUTING.md). Add unit tests for any new or changed functionality. Lint and test your code using [Grunt](http://gruntjs.com/).
 
@@ -284,57 +35,7 @@ Please report documentation issues in [the documentation project](https://github
 
 ### Development
 
-#### Install Less.js
-
-Start by either [downloading this project][download] manually, or in the command line:
-
-```shell
-git clone https://github.com/less/less.js.git "less"
-```
-and then `cd less`.
-
-
-#### Install dependencies
-
-To install all the dependencies for less development, run:
-
-```shell
-npm install
-```
-
-If you haven't run grunt before, install grunt-cli globally so you can just run `grunt`
-
-```shell
-npm install grunt-cli -g
-```
-
-You should now be able to build Less.js, run tests, benchmarking, and other tasks listed in the Gruntfile.
-
-## Using Less.js Grunt
-
-Tests, benchmarking and building is done using Grunt `~0.4.1`. If you haven't used [Grunt](http://gruntjs.com/) before, be sure to check out the [Getting Started](http://gruntjs.com/getting-started) guide, as it explains how to install and use Grunt plugins, which are necessary for development with Less.js.
-
-The Less.js [Gruntfile](Gruntfile.js) is configured with the following "convenience tasks" :
-
-#### test - `grunt`
-Runs jshint, nodeunit and headless jasmine tests using [phantomjs](http://code.google.com/p/phantomjs/). You must have phantomjs installed for the jasmine tests to run.
-
-#### test - `grunt benchmark`
-Runs the benchmark suite.
-
-#### build for testing browser - 'grunt browser'
-This builds less.js and puts it in 'test/browser/less.js'
-
-#### build - `grunt stable | grunt beta | grunt alpha`
-Builds Less.js from from the `/lib/less` source files. This is done by the developer releasing a new release, do not do this if you are creating a pull request.
-
-#### readme - `grunt readme`
-Build the README file from [a template](build/README.md) to ensure that metadata is up-to-date and (more likely to be) correct.
-
-Please review the [Gruntfile](Gruntfile.js) to become acquainted with the other available tasks.
-
-**Please note** that if you have any issues installing dependencies or running any of the Gruntfile commands, please make sure to uninstall any previous versions, both in the local node_modules directory, and clear your global npm cache, and then try running `npm install` again. After that if you still have issues, please let us know about it so we can help.
-
+Read [Developing Less](http://lesscss.org/usage/#developing-less).
 
 ## Release History
 See the [changelog](CHANGELOG.md)
@@ -347,5 +48,4 @@ Licensed under the [Apache License](LICENSE).
 
 [so]: http://stackoverflow.com/questions/tagged/twitter-bootstrap+less "StackOverflow.com"
 [issues]: https://github.com/less/less.js/issues "GitHub Issues for Less.js"
-[wiki]: https://github.com/less/less.js/wiki "The official wiki for Less.js"
 [download]: https://github.com/less/less.js/zipball/master "Download Less.js"

From bf9c59025bab7401299e8feb3bb26b3b039499c0 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Fri, 21 Feb 2014 11:03:38 +0000
Subject: [PATCH 26/29] Fixed that in some situations a mixin call into a
 referenced file wouldn't import media queries. Fixes #1469

---
 lib/less/tree/media.js                 |  1 +
 test/css/import-reference.css          | 27 ++++++++++++++++++++++----
 test/less/import-reference.less        | 11 +++++++----
 test/less/import/import-reference.less |  8 ++++++++
 4 files changed, 39 insertions(+), 8 deletions(-)

diff --git a/lib/less/tree/media.js b/lib/less/tree/media.js
index 4531cf4c..095e43e8 100644
--- a/lib/less/tree/media.js
+++ b/lib/less/tree/media.js
@@ -74,6 +74,7 @@ tree.Media.prototype = {
     },
     markReferenced: function () {
         var i, rules = this.rules[0].rules;
+        this.rules[0].markReferenced();
         this.isReferenced = true;
         for (i = 0; i < rules.length; i++) {
             if (rules[i].markReferenced) {
diff --git a/test/css/import-reference.css b/test/css/import-reference.css
index d61df816..f25f4b1d 100644
--- a/test/css/import-reference.css
+++ b/test/css/import-reference.css
@@ -1,7 +1,17 @@
-/*
-  The media statement above is invalid (no selector)
-  We should ban invalid media queries with properties and no selector?
-*/
+input[type="text"].class#id[attr=32]:not(1) {
+  color: white;
+}
+div#id.class[a=1][b=2].class:not(1) {
+  color: white;
+}
+@media print {
+  .class {
+    color: blue;
+  }
+  .class .sub {
+    width: 42;
+  }
+}
 .visible {
   color: red;
 }
@@ -47,3 +57,12 @@
 .visible {
   extend: test;
 }
+.test-mediaq-import {
+  color: green;
+  test: 340px;
+}
+@media (max-size: 450px) {
+  .test-mediaq-import {
+    color: red;
+  }
+}
diff --git a/test/less/import-reference.less b/test/less/import-reference.less
index cf9da168..93160ab5 100644
--- a/test/less/import-reference.less
+++ b/test/less/import-reference.less
@@ -1,10 +1,6 @@
 @import (reference) url("import-once.less");
 @import (reference) url("css-3.less");
 @import (reference) url("media.less");
-/*
-  The media statement above is invalid (no selector)
-  We should ban invalid media queries with properties and no selector?
-*/
 @import (reference) url("import/import-reference.less");
 
 .b {
@@ -15,4 +11,11 @@
 
 .visible:extend(.z all) {
   extend: test;
+}
+
+.test-mediaq-import {
+  .mixin-with-mediaq(340px);
+}
+
+.class:extend(.class all) {
 }
\ No newline at end of file
diff --git a/test/less/import/import-reference.less b/test/less/import/import-reference.less
index 9eac45fc..c77f692e 100644
--- a/test/less/import/import-reference.less
+++ b/test/less/import/import-reference.less
@@ -40,4 +40,12 @@
     pulled-in: yes;
   }
   /* comment pulled in */
+}
+@max-size: 450px;
+.mixin-with-mediaq(@num) {
+  color: green;
+  test: @num;
+  @media (max-size: @max-size) {
+    color: red;
+  }
 }
\ No newline at end of file

From 7c90acaae62fbe1d26c4778974703d857bc6b213 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Fri, 21 Feb 2014 11:22:42 +0000
Subject: [PATCH 27/29] Fix a small scope issue with mixins when using parent
 selectors, introduced in 1.6.2. Fixes #1877

---
 lib/less/tree/ruleset.js                      | 33 +++++++++++--------
 test/css/scope.css                            |  3 ++
 .../errors/mixin-not-visible-in-scope-1.less  |  9 +++++
 .../errors/mixin-not-visible-in-scope-1.txt   |  4 +++
 test/less/scope.less                          | 25 ++++++++++++++
 5 files changed, 60 insertions(+), 14 deletions(-)
 create mode 100644 test/less/errors/mixin-not-visible-in-scope-1.less
 create mode 100644 test/less/errors/mixin-not-visible-in-scope-1.txt

diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index 7571b0e7..d657976d 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -111,20 +111,25 @@ tree.Ruleset.prototype = {
             rule = rsRules[i];
             if (! (rule instanceof tree.mixin.Definition || rule instanceof tree.DetachedRuleset)) {
                 rsRules[i] = rule = rule.eval ? rule.eval(env) : rule;
-                // for rulesets, check if it is a css guard and can be removed
-                if (rule instanceof tree.Ruleset && rule.selectors && rule.selectors.length === 1) {
-                    // check if it can be folded in (e.g. & where)
-                    if (rule.selectors[0].isJustParentSelector()) {
-                        rsRules.splice(i--, 1);
-                        // cannot call if there is no selector, so we can just continue
-                        if (!rule.selectors[0].evaldCondition) {
-                            continue;
-                        }
-                        for(var j = 0; j < rule.rules.length; j++) {
-                            subRule = rule.rules[j];
-                            if (!(subRule instanceof tree.Rule) || !subRule.variable) {
-                                rsRules.splice(++i, 0, subRule);
-                            }
+            }
+        }
+        
+        // Evaluate everything else
+        for (i = 0; i < rsRules.length; i++) {
+            rule = rsRules[i];
+            // for rulesets, check if it is a css guard and can be removed
+            if (rule instanceof tree.Ruleset && rule.selectors && rule.selectors.length === 1) {
+                // check if it can be folded in (e.g. & where)
+                if (rule.selectors[0].isJustParentSelector()) {
+                    rsRules.splice(i--, 1);
+                    // cannot call if there is no selector, so we can just continue
+                    if (!rule.selectors[0].evaldCondition) {
+                        continue;
+                    }
+                    for(var j = 0; j < rule.rules.length; j++) {
+                        subRule = rule.rules[j];
+                        if (!(subRule instanceof tree.Rule) || !subRule.variable) {
+                            rsRules.splice(++i, 0, subRule);
                         }
                     }
                 }
diff --git a/test/css/scope.css b/test/css/scope.css
index baa05523..0e4c17d5 100644
--- a/test/css/scope.css
+++ b/test/css/scope.css
@@ -33,3 +33,6 @@
   scope: 'top level';
   sub-scope-only: 'inside';
 }
+#parentSelectorScope {
+  prop: #ffffff;
+}
diff --git a/test/less/errors/mixin-not-visible-in-scope-1.less b/test/less/errors/mixin-not-visible-in-scope-1.less
new file mode 100644
index 00000000..2842613e
--- /dev/null
+++ b/test/less/errors/mixin-not-visible-in-scope-1.less
@@ -0,0 +1,9 @@
+.something {
+    & {
+        .a {value: a}
+    }
+
+    & {
+        .b {.a} // was Err. before 1.6.2
+    }
+}
\ No newline at end of file
diff --git a/test/less/errors/mixin-not-visible-in-scope-1.txt b/test/less/errors/mixin-not-visible-in-scope-1.txt
new file mode 100644
index 00000000..15e64dc2
--- /dev/null
+++ b/test/less/errors/mixin-not-visible-in-scope-1.txt
@@ -0,0 +1,4 @@
+NameError: .a is undefined in {path}mixin-not-visible-in-scope-1.less on line 7, column 13:
+6     & {
+7         .b {.a} // was Err. before 1.6.2
+8     }
diff --git a/test/less/scope.less b/test/less/scope.less
index 36d37061..475b1f6d 100644
--- a/test/less/scope.less
+++ b/test/less/scope.less
@@ -76,4 +76,29 @@
   @subScopeOnly: 'inside';
   //use the mixin
   .mixinNoParam();
+}
+#parentSelectorScope {
+  @col: white;
+  & {
+    @col: black;
+  }
+  prop: @col;
+  & {
+    @col: black;
+  }
+}
+.test-empty-mixin() {
+}
+#parentSelectorScopeMixins {
+  & {
+    .test-empty-mixin() {
+      should: never seee 1;
+    }
+  }
+  .test-empty-mixin();
+  & {
+    .test-empty-mixin() {
+      should: never seee 2;
+    }
+  }
 }
\ No newline at end of file

From ca06fee982cb32b0f3253e3f9eb611f622e34ab5 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Fri, 21 Feb 2014 11:32:28 +0000
Subject: [PATCH 28/29] when in lint mode, report errors from creating css.
 Fixes #1786

---
 bin/lessc | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/bin/lessc b/bin/lessc
index b36c062a..7530b307 100755
--- a/bin/lessc
+++ b/bin/lessc
@@ -352,8 +352,9 @@ var parseLessFile = function (e, data) {
                 sys.print(file + " ")
             }
             sys.print("\n");
-        } else if(!options.lint) {
+        } else {
             try {
+	        if (options.lint) { writeSourceMap = function() {} }
                 var css = tree.toCSS({
                     silent: options.silent,
                     verbose: options.verbose,
@@ -374,15 +375,17 @@ var parseLessFile = function (e, data) {
                     strictUnits: options.strictUnits,
                     urlArgs: options.urlArgs
                 });
-                if (output) {
-                    ensureDirectory(output);
-                    fs.writeFileSync(output, css, 'utf8');
-                    if (options.verbose) {
-                        console.log('lessc: wrote ' + output);
-                    }
-                } else {
-                    sys.print(css);
-                }
+		if(!options.lint) {
+                    if (output) {
+                        ensureDirectory(output);
+                        fs.writeFileSync(output, css, 'utf8');
+                        if (options.verbose) {
+                            console.log('lessc: wrote ' + output);
+                        }
+                    } else {
+                        sys.print(css);
+		    }
+		}
             } catch (e) {
                 less.writeError(e, options);
                 currentErrorcode = 2;

From 5ab0e086657d926a1bec4c5fb6af6740de178b7d Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Fri, 21 Feb 2014 12:37:40 +0000
Subject: [PATCH 29/29] Do not evaluate css with guards if the guards fail.
 Fixes #1873

---
 lib/less/tree/ruleset.js  | 20 ++++++++++++++------
 test/less/css-guards.less |  3 +++
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/lib/less/tree/ruleset.js b/lib/less/tree/ruleset.js
index d657976d..19023004 100644
--- a/lib/less/tree/ruleset.js
+++ b/lib/less/tree/ruleset.js
@@ -20,7 +20,8 @@ tree.Ruleset.prototype = {
     },
     eval: function (env) {
         var thisSelectors = this.selectors, selectors, 
-            selCnt, i, defaultFunc = tree.defaultFunc;
+            selCnt, selector, i, defaultFunc = tree.defaultFunc, hasOnePassingSelector = false;
+
         if (thisSelectors && (selCnt = thisSelectors.length)) {
             selectors = [];
             defaultFunc.error({
@@ -28,9 +29,15 @@ tree.Ruleset.prototype = {
                 message: "it is currently only allowed in parametric mixin guards," 
             });
             for (i = 0; i < selCnt; i++) {
-                selectors.push(thisSelectors[i].eval(env));
+                selector = thisSelectors[i].eval(env);
+                selectors.push(selector);
+                if (selector.evaldCondition) {
+                    hasOnePassingSelector = true;
+                }
             }
             defaultFunc.reset();  
+        } else {
+            hasOnePassingSelector = true;
         }
 
         var rules = this.rules ? this.rules.slice(0) : null,
@@ -45,6 +52,10 @@ tree.Ruleset.prototype = {
         if(this.debugInfo) {
             ruleset.debugInfo = this.debugInfo;
         }
+        
+        if (!hasOnePassingSelector) {
+            rules.length = 0;
+        }
 
         // push the current ruleset to the frames stack
         var envFrames = env.frames;
@@ -122,10 +133,7 @@ tree.Ruleset.prototype = {
                 // check if it can be folded in (e.g. & where)
                 if (rule.selectors[0].isJustParentSelector()) {
                     rsRules.splice(i--, 1);
-                    // cannot call if there is no selector, so we can just continue
-                    if (!rule.selectors[0].evaldCondition) {
-                        continue;
-                    }
+
                     for(var j = 0; j < rule.rules.length; j++) {
                         subRule = rule.rules[j];
                         if (!(subRule instanceof tree.Rule) || !subRule.variable) {
diff --git a/test/less/css-guards.less b/test/less/css-guards.less
index 6dd1cd68..85ec8d29 100644
--- a/test/less/css-guards.less
+++ b/test/less/css-guards.less
@@ -97,3 +97,6 @@
   .scope-check();
   @k:4px;
 }
+.errors-if-called when (@c = never) {
+  .mixin-doesnt-exist();
+}
\ No newline at end of file