Don't separate out media queries after one has bubbled (#1933)

Closes #777

Author: nex3

CHANGELOG.md

@@ -8,6 +8,9 @@
   native CSS `filter` functions. This is in addition to number values which were
   already allowed.
 
+* Fix a cosmetic bug where an outer rule could be duplicated after nesting was
+  resolved, instead of re-using a shared rule.
+
 ## 1.61.0
 
 * **Potentially breaking change:** Drop support for End-of-Life Node.js 12.

lib/src/ast/css/modifiable/at_rule.dart

@@ -22,6 +22,12 @@ class ModifiableCssAtRule extends ModifiableCssParentNode implements CssAtRule {
 
   T accept<T>(ModifiableCssVisitor<T> visitor) => visitor.visitCssAtRule(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssAtRule &&
+      name == other.name &&
+      value == other.value &&
+      isChildless == other.isChildless;
+
   ModifiableCssAtRule copyWithoutChildren() =>
       ModifiableCssAtRule(name, span, childless: isChildless, value: value);
 

lib/src/ast/css/modifiable/keyframe_block.dart

@@ -4,6 +4,7 @@
 
 import 'package:source_span/source_span.dart';
 
+import '../../../utils.dart';
 import '../../../visitor/interface/modifiable_css.dart';
 import '../keyframe_block.dart';
 import '../value.dart';
@@ -20,6 +21,10 @@ class ModifiableCssKeyframeBlock extends ModifiableCssParentNode
   T accept<T>(ModifiableCssVisitor<T> visitor) =>
       visitor.visitCssKeyframeBlock(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssKeyframeBlock &&
+      listEquals(selector.value, other.selector.value);
+
   ModifiableCssKeyframeBlock copyWithoutChildren() =>
       ModifiableCssKeyframeBlock(selector, span);
 }

lib/src/ast/css/modifiable/media_rule.dart

@@ -4,6 +4,7 @@
 
 import 'package:source_span/source_span.dart';
 
+import '../../../utils.dart';
 import '../../../visitor/interface/modifiable_css.dart';
 import '../media_query.dart';
 import '../media_rule.dart';
@@ -25,6 +26,9 @@ class ModifiableCssMediaRule extends ModifiableCssParentNode
   T accept<T>(ModifiableCssVisitor<T> visitor) =>
       visitor.visitCssMediaRule(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssMediaRule && listEquals(queries, other.queries);
+
   ModifiableCssMediaRule copyWithoutChildren() =>
       ModifiableCssMediaRule(queries, span);
 }

lib/src/ast/css/modifiable/node.dart

@@ -66,6 +66,9 @@ abstract class ModifiableCssParentNode extends ModifiableCssNode
       : _children = children,
         children = UnmodifiableListView(children);
 
+  /// Returns whether [this] is equal to [other], ignoring their child nodes.
+  bool equalsIgnoringChildren(ModifiableCssNode other);
+
   /// Returns a copy of [this] with an empty [children] list.
   ///
   /// This is *not* a deep copy. If other parts of this node are modifiable,

lib/src/ast/css/modifiable/style_rule.dart

@@ -32,6 +32,9 @@ class ModifiableCssStyleRule extends ModifiableCssParentNode
   T accept<T>(ModifiableCssVisitor<T> visitor) =>
       visitor.visitCssStyleRule(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssStyleRule && other.selector == selector;
+
   ModifiableCssStyleRule copyWithoutChildren() =>
       ModifiableCssStyleRule(_selector, span,
           originalSelector: originalSelector);

lib/src/ast/css/modifiable/stylesheet.dart

@@ -18,6 +18,9 @@ class ModifiableCssStylesheet extends ModifiableCssParentNode
   T accept<T>(ModifiableCssVisitor<T> visitor) =>
       visitor.visitCssStylesheet(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssStylesheet;
+
   ModifiableCssStylesheet copyWithoutChildren() =>
       ModifiableCssStylesheet(span);
 }

lib/src/ast/css/modifiable/supports_rule.dart

@@ -20,6 +20,9 @@ class ModifiableCssSupportsRule extends ModifiableCssParentNode
   T accept<T>(ModifiableCssVisitor<T> visitor) =>
       visitor.visitCssSupportsRule(this);
 
+  bool equalsIgnoringChildren(ModifiableCssNode other) =>
+      other is ModifiableCssSupportsRule && condition == other.condition;
+
   ModifiableCssSupportsRule copyWithoutChildren() =>
       ModifiableCssSupportsRule(condition, span);
 }

lib/src/visitor/async_evaluate.dart

@@ -3343,8 +3343,14 @@ class _EvaluateVisitor
       if (parent.hasFollowingSibling) {
         // A node with siblings must have a parent
         var grandparent = parent.parent!;
-        parent = parent.copyWithoutChildren();
-        grandparent.addChild(parent);
+        if (parent.equalsIgnoringChildren(grandparent.children.last)) {
+          // If we've already made a copy of [parent] and nothing else has been
+          // added after it, re-use it.
+          parent = grandparent.children.last as ModifiableCssParentNode;
+        } else {
+          parent = parent.copyWithoutChildren();
+          grandparent.addChild(parent);
+        }
       }
     }
 

lib/src/visitor/evaluate.dart

@@ -5,7 +5,7 @@
 // DO NOT EDIT. This file was generated from async_evaluate.dart.
 // See tool/grind/synchronize.dart for details.
 //
-// Checksum: 06d1dd221c149650242b3e09b3f507125606bf0f
+// Checksum: 17862153344c8577d780b3e039a1ce5ebb774c17
 //
 // ignore_for_file: unused_import
 
@@ -3314,8 +3314,14 @@ class _EvaluateVisitor
       if (parent.hasFollowingSibling) {
         // A node with siblings must have a parent
         var grandparent = parent.parent!;
-        parent = parent.copyWithoutChildren();
-        grandparent.addChild(parent);
+        if (parent.equalsIgnoringChildren(grandparent.children.last)) {
+          // If we've already made a copy of [parent] and nothing else has been
+          // added after it, re-use it.
+          parent = grandparent.children.last as ModifiableCssParentNode;
+        } else {
+          parent = parent.copyWithoutChildren();
+          grandparent.addChild(parent);
+        }
       }
     }