remove duplicate rules automatically

lib/less/tree/ruleset.js

@@ -114,6 +114,7 @@ tree.Ruleset.prototype = {
     toCSS: function (context, env) {
         var css = [],      // The CSS output
             rules = [],    // node.Rule instances
+           _rules = [],    //
             rulesets = [], // node.Ruleset instances
             paths = [],    // Current selectors
             selector,      // The fully rendered selector
@@ -163,7 +164,15 @@ tree.Ruleset.prototype = {
                     return p.map(function (s) {
                         return s.toCSS(env);
                     }).join('').trim();
-                }).join( env.compress ? ',' : ',\n');
+                }).join(env.compress ? ',' : ',\n');
+
+                // Remove duplicates
+                for (var i = rules.length - 1; i >= 0; i--) {
+                    if (_rules.indexOf(rules[i]) === -1) {
+                        _rules.unshift(rules[i]);
+                    }
+                }
+                rules = _rules;
 
                 css.push(selector,
                         (env.compress ? '{' : ' {\n  ') +

test/css/functions.css

@@ -29,8 +29,8 @@
 }
 #built-in .is-a {
   color: true;
-  color: true;
-  color: true;
+  color1: true;
+  color2: true;
   keyword: true;
   number: true;
   string: true;

test/css/javascript.css

@@ -18,5 +18,5 @@
 }
 .arrays {
   ary: "1, 2, 3";
-  ary: "1, 2, 3";
+  ary1: "1, 2, 3";
 }

test/css/mixins-args.css

@@ -1,5 +1,7 @@
 #hidden {
   color: transparent;
+}
+#hidden1 {
   color: transparent;
 }
 .two-args {
@@ -49,10 +51,6 @@ body {
 #var-inside {
   width: 10px;
 }
-.id-class {
-  color: red;
-  color: red;
-}
 .arguments {
   border: 1px solid #000000;
   width: 1px;

test/css/strings.css

@@ -35,6 +35,6 @@
 .mix-mul-class {
   color: #0000ff;
   color: #ff0000;
-  color: #0000ff;
+  color: #000000;
   color: #ffa500;
 }

test/less/functions.less

@@ -33,8 +33,8 @@
 
   .is-a {
     color: iscolor(#ddd);
-    color: iscolor(red);
-    color: iscolor(rgb(0, 0, 0));
+    color1: iscolor(red);
+    color2: iscolor(rgb(0, 0, 0));
     keyword: iskeyword(hello);
     number: isnumber(32);
     string: isstring("hello");

test/less/javascript.less

@@ -23,5 +23,5 @@
     @ary:  1, 2, 3;
     @ary2: 1  2  3;
     ary: `@{ary}.join(', ')`;
-    ary: `@{ary2}.join(', ')`;
+    ary1: `@{ary2}.join(', ')`;
 }

test/less/mixins-args.less

@@ -19,6 +19,9 @@
 
 #hidden {
   .hidden;
+}
+
+#hidden1 {
   .hidden();
 }
 
@@ -96,16 +99,6 @@ body {
 }
 #var-inside { .var-inside; }
 
-// # mixins
-
-#id-mixin () {
-    color: red;
-}
-.id-class {
-    #id-mixin();
-    #id-mixin;
-}
-
 .mixin-arguments (@width: 0px, ...) {
     border: @arguments;
     width: @width;

test/less/strings.less

@@ -46,6 +46,6 @@
 .mix-mul-class {
     .mix-mul(blue);
     .mix-mul(red);
-    .mix-mul(blue);
+    .mix-mul(black);
     .mix-mul(orange);
 }