Fix for 2991

Author: Olivier Nicodemi

packages/less/src/less/visitors/to-css-visitor.js

@@ -39,9 +39,9 @@ class CSSVisitorUtils {
             ? (rulesetNode.paths.length > 0) : false;
     }
 
-    resolveVisibility(node, originalRules) {
+    resolveVisibility(node) {
         if (!node.blocksVisibility()) {
-            if (this.isEmpty(node) && !this.containsSilentNonBlockedChild(originalRules)) {
+            if (this.isEmpty(node)) {
                 return ;
             }
 

packages/test-data/less/_main/import-reference-issues/comments-2991.less

@@ -1,22 +1,25 @@
 .referenced {
-    // line comment is enough to reproduce it
+	// This file should not output anything if referenced.
     @media (hover) {
-        // sezam
+        // This file should not output anything if referenced.
     }
-    // repeat to prove point
+	// This file should not output anything if referenced.
     @media (hover) {
-        // sezam
+		// This file should not output anything if referenced.
     }
-    // but block comment is not, huh
+	// This file should not output anything if referenced.
     @media (hover) {
-        /* salabim */
+        /* This file should not output anything if referenced. */
     }
-    // following block does not output, needs line comment
+	// This file should not output anything if referenced.
     @media (hover) {
         color: #000000;
     }
 }
-// needs to be nested to fail
+// This file should not output anything if referenced.
 @media (hover) {
-    // sezam
+	// This file should not output anything if referenced.
+}
+@media (hover) {
+	/* This file should not output anything if referenced. */
 }