default function: added error when used with css-guards. updated tests.

lib/less/tree/ruleset.js

@@ -19,12 +19,18 @@ tree.Ruleset.prototype = {
         }
     },
     eval: function (env) {
-        var thisSelectors = this.selectors, selectors, selCnt, i;
+        var thisSelectors = this.selectors, selectors, 
+            selCnt, i, defaultFunc = tree.defaultFunc;
         if (thisSelectors && (selCnt = thisSelectors.length)) {
             selectors = [];
+            defaultFunc.error({
+                type: "Syntax", 
+                message: "it is currently only allowed in parametric mixin guards," 
+            });
             for (i = 0; i < selCnt; i++) {
                 selectors.push(thisSelectors[i].eval(env));
             }
+            defaultFunc.reset();  
         }
 
         var rules = this.rules ? this.rules.slice(0) : null,

test/css/mixins-guards-default-func.css

@@ -112,3 +112,9 @@ guard-default-multi-4 {
   always: 2;
   case: 2;
 }
+guard-default-scopes-3 {
+  3: when default;
+}
+guard-default-scopes-1 {
+  1: no condition;
+}

test/less/errors/css-guard-default-func.less

@@ -0,0 +1,4 @@
+
+selector when (default()) {
+    color: red;
+}

test/less/errors/css-guard-default-func.txt

@@ -0,0 +1,4 @@
+SyntaxError: error evaluating function `default`: it is currently only allowed in parametric mixin guards, in {path}css-guard-default-func.less on line 2, column 16:
+1 
+2 selector when (default()) {
+3     color: red;

test/less/mixins-guards-default-func.less

@@ -157,3 +157,23 @@ guard-default-multi-4 {
     .m(1);
     .m(2);
 }
+
+// default & scope
+
+guard-default-scopes {
+    .s1() {.m(@v)                  {1: no condition}}
+    .s2() {.m(@v) when (@v)        {2: when true}}
+    .s3() {.m(@v) when (default()) {3: when default}}
+
+    &-3 {
+        .s2();
+        .s3();
+        .m(false);
+    }
+    
+    &-1 {
+        .s1();
+        .s3();
+        .m(false);
+    }
+}