don't merge rulesets if between them a ruleset with same specificity (f…

…ixes #264)

lib/compressor/restructure/rejoinRuleset.js

@@ -8,8 +8,8 @@ module.exports = function rejoinRuleset(node, parent, array, i) {
         return null;
     }
 
-    var compareMarkers = {};
-    compareMarkers[selector[0].info.compareMarker] = true;
+    var nodeCompareMarker = selector[0].info.compareMarker;
+    var skippedCompareMarkers = {};
 
     for (i = i + 1; i < array.length; i++) {
         var next = array[i];
@@ -24,6 +24,12 @@ module.exports = function rejoinRuleset(node, parent, array, i) {
 
         var nextFirstSelector = next.selector.selectors[0];
         var nextBlock = next.block.declarations;
+        var nextCompareMarker = nextFirstSelector.info.compareMarker;
+
+        // if next ruleset has same marked as one of skipped then stop joining
+        if (nextCompareMarker in skippedCompareMarkers) {
+            return;
+        }
 
         // try to join by selectors
         if (selector.length === 1) {
@@ -41,10 +47,9 @@ module.exports = function rejoinRuleset(node, parent, array, i) {
         }
 
         // try to join by properties
-        var nextCompareMarker = nextFirstSelector.info.compareMarker;
-        var equalBlocks = true;
-
         if (block.length === nextBlock.length) {
+            var equalBlocks = true;
+
             for (var j = 0; j < block.length; j++) {
                 if (block[j].info.s !== nextBlock[j].info.s) {
                     equalBlocks = false;
@@ -62,17 +67,18 @@ module.exports = function rejoinRuleset(node, parent, array, i) {
                     }
                 }
 
-                compareMarkers[nextCompareMarker] = true;
                 array.splice(i, 1);
                 i--;
 
                 continue;
             }
         }
 
-        // go to next ruleset if simpleselectors has no equal specifity and element selector
-        if (nextCompareMarker in compareMarkers) {
+        // go to next ruleset if current one can be skipped (has no equal specificity nor element selector)
+        if (nextCompareMarker === nodeCompareMarker) {
             return;
         }
+
+        skippedCompareMarkers[nextCompareMarker] = true;
     }
 };

test/fixture/compress/restructure.merge/7.css

@@ -0,0 +1,15 @@
+/*
+  issue #264 don't merge rulesets if between there is a ruleset with same specificity
+*/
+
+.notification-banner.drop {
+    top: -50px
+}
+
+.notification-banner.drop.in {
+    top: 0
+}
+
+.notification-banner.drop.out {
+    top: -50px
+}

test/fixture/compress/restructure.merge/7.min.css

@@ -0,0 +1 @@
+.notification-banner.drop{top:-50px}.notification-banner.drop.in{top:0}.notification-banner.drop.out{top:-50px}