Add import visitor

Makefile

@@ -40,6 +40,7 @@ less:
 	      ${SRC}/tree.js\
 	      ${SRC}/env.js\
 	      ${SRC}/visitor.js\
+	      ${SRC}/import-visitor.js\
 	      ${SRC}/browser.js\
 	      build/amd.js >> ${DIST}
 	@@echo "})(window);" >> ${DIST}
@@ -62,6 +63,7 @@ rhino:
 	      ${SRC}/parser.js\
 	      ${SRC}/env.js\
 	      ${SRC}/visitor.js\
+	      ${SRC}/import-visitor.js\
 	      ${SRC}/functions.js\
 	      ${SRC}/colors.js\
 	      ${SRC}/tree/*.js\

lib/less/import-visitor.js

@@ -0,0 +1,17 @@
+(function (tree) {
+    tree.importVisitor = function(root) {
+        this._visitor = new tree.visitor(this);
+        this._visitor.visit(root);
+    };
+
+    tree.importVisitor.prototype = {
+        visitImport: function (importNode, visitArgs) {
+
+            return importNode;
+        },
+        visitRule: function (ruleNode, visitArgs) {
+            visitArgs.visitDeeper = false;
+            return ruleNode;
+        }
+    };
+})(require('./tree'));

lib/less/index.js

@@ -214,5 +214,6 @@ require('./env');
 require('./functions');
 require('./colors');
 require('./visitor.js');
+require('./import-visitor.js');
 
 for (var k in less) { exports[k] = less[k]; }

lib/less/parser.js

@@ -467,6 +467,8 @@ less.Parser = function Parser(env) {
                     ]
                 };
             }
+
+            new tree.importVisitor(root);
             
             finish = function (e) {
                 e = error || e || parser.imports.error;

lib/less/tree/extend.js

@@ -9,7 +9,7 @@ tree.Extend = function Extend(elements, option, index) {
 tree.Extend.prototype = {
     type: "Extend",
     accept: function (visitor) {
-        this.selector = visitor.visit(this.ruleset);
+        this.selector = visitor.visit(this.selector);
     },
     eval: function (env, selectors) {
         var selfSelectors = findSelfSelectors(selectors || env.selectors),

lib/less/visitor.js

@@ -20,15 +20,15 @@
                 visitArgs;
             if (func) {
                 visitArgs = {visitDeeper: true};
-                node = func(node);
+                node = func(node, visitArgs);
             }
-            if ((!visitArgs || visitArgs.visitDeeper) && node.accept) {
+            if ((!visitArgs || visitArgs.visitDeeper) && node && node.accept) {
                 node.accept(this);
             }
             return node;
         },
         visitArray: function(nodes) {
-            var i, newNodes;
+            var i, newNodes = [];
             for(i = 0; i < nodes.length; i++) {
                 var evald = this.visit(nodes[i]);
                 if (evald instanceof Array) {