Allow comparing colors and strings. Fix a bug whereby sometimes a mixin-call or import would disappear. This makes the import test fail consistently instead of once out of 8 times depending on async order I think.

lib/less/tree/anonymous.js

@@ -7,7 +7,21 @@ tree.Anonymous.prototype = {
     toCSS: function () {
         return this.value;
     },
-    eval: function () { return this }
+    eval: function () { return this },
+    compare: function (x) {
+        if (!x.toCSS) {
+            return -1;
+        }
+        
+        var left = this.toCSS(),
+            right = x.toCSS();
+        
+        if (left === right) {
+            return 0;
+        }
+        
+        return left < right ? -1 : 1;
+    }
 };
 
 })(require('../tree'));

lib/less/tree/color.js

@@ -94,6 +94,16 @@ tree.Color.prototype = {
             i = (i > 255 ? 255 : (i < 0 ? 0 : i)).toString(16);
             return i.length === 1 ? '0' + i : i;
         }).join('');
+    },
+    compare: function (x) {
+        if (!x.rgb) {
+            return -1;
+        }
+        
+        return (x.rgb[0] === this.rgb[0] &&
+            x.rgb[1] === this.rgb[1] &&
+            x.rgb[2] === this.rgb[2] &&
+            x.alpha === this.alpha) ? 0 : -1;
     }
 };
 

lib/less/tree/quoted.js

@@ -23,6 +23,20 @@ tree.Quoted.prototype = {
             return ('value' in v) ? v.value : v.toCSS();
         });
         return new(tree.Quoted)(this.quote + value + this.quote, value, this.escaped, this.index);
+    },
+    compare: function (x) {
+        if (!x.toCSS) {
+            return -1;
+        }
+        
+        var left = this.toCSS(),
+            right = x.toCSS();
+        
+        if (left === right) {
+            return 0;
+        }
+        
+        return left < right ? -1 : 1;
     }
 };
 

lib/less/tree/ruleset.js

@@ -10,7 +10,8 @@ tree.Ruleset.prototype = {
     eval: function (env) {
         var selectors = this.selectors && this.selectors.map(function (s) { return s.eval(env) });
         var ruleset = new(tree.Ruleset)(selectors, this.rules.slice(0), this.strictImports);
-
+        var rules = [];
+        
         ruleset.root = this.root;
         ruleset.allowImports = this.allowImports;
 
@@ -21,10 +22,13 @@ tree.Ruleset.prototype = {
         if (ruleset.root || ruleset.allowImports || !ruleset.strictImports) {
             for (var i = 0; i < ruleset.rules.length; i++) {
                 if (ruleset.rules[i] instanceof tree.Import) {
-                    Array.prototype.splice
-                         .apply(ruleset.rules, [i, 1].concat(ruleset.rules[i].eval(env)));
+                    rules = rules.concat(ruleset.rules[i].eval(env));
+                } else {
+                    rules.push(ruleset.rules[i]);
                 }
             }
+            ruleset.rules = rules;
+            rules = [];
         }
 
         // Store the frames around mixin definitions,
@@ -38,10 +42,12 @@ tree.Ruleset.prototype = {
         // Evaluate mixin calls.
         for (var i = 0; i < ruleset.rules.length; i++) {
             if (ruleset.rules[i] instanceof tree.mixin.Call) {
-                Array.prototype.splice
-                     .apply(ruleset.rules, [i, 1].concat(ruleset.rules[i].eval(env)));
+                rules = rules.concat(ruleset.rules[i].eval(env));
+            } else {
+                rules.push(ruleset.rules[i]);
             }
         }
+        ruleset.rules = rules;
 
         // Evaluate everything else
         for (var i = 0, rule; i < ruleset.rules.length; i++) {