support comments. Add failing test case for when mixin call does not have parent selectors

lib/less/parser.js

@@ -575,9 +575,9 @@ less.Parser = function Parser(env) {
                 if (input.charAt(i) !== '/') return;
 
                 if (input.charAt(i + 1) === '/') {
-                    return new(tree.Comment)($(/^\/\/.*/), true);
+                    return new(tree.Comment)($(/^\/\/.*/), true, i, env.currentFileInfo);
                 } else if (comment = $(/^\/\*(?:[^*]|\*+[^\/*])*\*+\/\n?/)) {
-                    return new(tree.Comment)(comment);
+                    return new(tree.Comment)(comment, false, i, env.currentFileInfo);
                 }
             },
 

lib/less/tree/comment.js

@@ -1,15 +1,16 @@
 (function (tree) {
 
-tree.Comment = function (value, silent) {
+tree.Comment = function (value, silent, index, currentFileInfo) {
     this.value = value;
     this.silent = !!silent;
+    this.currentFileInfo = currentFileInfo;
 };
 tree.Comment.prototype = {
     type: "Comment",
     toCSS: function (env) {
-        return env.compress ? '' : this.value;
+        return (env.compress || (this.currentFileInfo && this.currentFileInfo.silent)) ? '' : this.value;
     },
-    eval: function () { return this }
+    eval: function () { return this; }
 };
 
 })(require('../tree'));

test/css/import-silent.css

@@ -1,13 +1,9 @@
 @media only screen and (max-width: 200px) {
   width: 480px;
 }
-@media (max-width: 1200px) {
-  /* a comment */
-}
 /*
-  The media statements - 1 is invalid (no selector) and 1 is just a comment
-  We should band invalid media queries solving the 1st case and not treat comments as rules,
-  solving the 2nd issue.
+  The media statement above is invalid (no selector)
+  We should ban invalid media queries with properties and no selector?
 */
 .visible {
   color: red;
@@ -41,6 +37,10 @@
 .b .c {
   color: green;
 }
+.y {
+  pulled-in: yes;
+}
+/* comment pulled in */
 .visible {
   extend: test;
 }

test/less/import-silent.less

@@ -2,9 +2,8 @@
 @import (silent) url("css-3.less");
 @import (silent) url("media.less");
 /*
-  The media statements - 1 is invalid (no selector) and 1 is just a comment
-  We should band invalid media queries solving the 1st case and not treat comments as rules,
-  solving the 2nd issue.
+  The media statement above is invalid (no selector)
+  We should ban invalid media queries with properties and no selector?
 */
 @import (silent) url("import/import-silent.less");
 
@@ -12,6 +11,8 @@
   .z();
 }
 
+.zz();
+
 .visible:extend(.z all) {
   extend: test;
 }

test/less/import/import-silent.less

@@ -31,4 +31,13 @@
   .hidden {
     hidden: true;
   }
+}
+
+/* comment is not output */
+
+.zz {
+  .y {
+    pulled-in: yes;
+  }
+  /* comment pulled in */
 }