improve import support with media features

lib/less/tree/directive.js

@@ -6,6 +6,7 @@ tree.Directive = function (name, value, features) {
 
     if (Array.isArray(value)) {
         this.ruleset = new(tree.Ruleset)([], value);
+        this.ruleset.allowImports = true;
     } else {
         this.value = value;
     }

lib/less/tree/import.js

@@ -57,13 +57,12 @@ tree.Import.prototype = {
         }
     },
     eval: function (env) {
-        var ruleset;
+        var ruleset, features = this.features && this.features.eval(env);
 
         if (this.css) {
-            this.features = this.features && this.features.eval(env);
             return this;
         } else {
-            ruleset = new(tree.Ruleset)(null, this.root.rules.slice(0));
+            ruleset = new(tree.Ruleset)([], this.root.rules.slice(0));
 
             for (var i = 0; i < ruleset.rules.length; i++) {
                 if (ruleset.rules[i] instanceof tree.Import) {
@@ -73,7 +72,7 @@ tree.Import.prototype = {
                                 [i, 1].concat(ruleset.rules[i].eval(env)));
                 }
             }
-            return ruleset.rules;
+            return this.features ? new(tree.Directive)('@media', ruleset.rules, this.features.value) : ruleset.rules;
         }
     }
 };

lib/less/tree/ruleset.js

@@ -11,12 +11,13 @@ tree.Ruleset.prototype = {
         var ruleset = new(tree.Ruleset)(selectors, this.rules.slice(0));
 
         ruleset.root = this.root;
+        ruleset.allowImports = this.allowImports;
 
         // push the current ruleset to the frames stack
         env.frames.unshift(ruleset);
 
         // Evaluate imports
-        if (ruleset.root) {
+        if (ruleset.root || ruleset.allowImports) {
             for (var i = 0; i < ruleset.rules.length; i++) {
                 if (ruleset.rules[i] instanceof tree.Import) {
                     Array.prototype.splice

test/css/import.css

@@ -16,3 +16,8 @@
   width: 10px;
   height: 30%;
 }
+@media screen and (max-width: 600px) {
+  body {
+    width: 100%;
+  }
+}

test/less/import.less

@@ -8,3 +8,4 @@
   width: 10px;
   height: @a + 10%;
 }
+@import "import/import-test-e" screen and (max-width: 600px);

test/less/import/import-test-e.less

@@ -0,0 +1,2 @@
+
+body { width: 100% }