Introduce ASIntegerMap, improve our changeset handling #trivial

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -327,7 +327,7 @@
 		CC0F886D1E4286FA00576FED /* ReferenceImages_iOS_10 in Resources */ = {isa = PBXBuildFile; fileRef = CC0F886A1E4286FA00576FED /* ReferenceImages_iOS_10 */; };
 		CC11F97A1DB181180024D77B /* ASNetworkImageNodeTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CC11F9791DB181180024D77B /* ASNetworkImageNodeTests.m */; };
 		CC2F65EE1E5FFB1600DA57C9 /* ASMutableElementMap.h in Headers */ = {isa = PBXBuildFile; fileRef = CC2F65EC1E5FFB1600DA57C9 /* ASMutableElementMap.h */; };
-		CC2F65EF1E5FFB1600DA57C9 /* ASMutableElementMap.mm in Sources */ = {isa = PBXBuildFile; fileRef = CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.mm */; };
+		CC2F65EF1E5FFB1600DA57C9 /* ASMutableElementMap.m in Sources */ = {isa = PBXBuildFile; fileRef = CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.m */; };
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 		CC3B20861C3F76D600798563 /* ASPendingStateController.mm in Sources */ = {isa = PBXBuildFile; fileRef = CC3B20821C3F76D600798563 /* ASPendingStateController.mm */; };
 		CC3B208A1C3F7A5400798563 /* ASWeakSet.h in Headers */ = {isa = PBXBuildFile; fileRef = CC3B20871C3F7A5400798563 /* ASWeakSet.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -343,6 +343,8 @@
 		CC55A70E1E529FA200594372 /* UIResponder+AsyncDisplayKit.m in Sources */ = {isa = PBXBuildFile; fileRef = CC55A70C1E529FA200594372 /* UIResponder+AsyncDisplayKit.m */; };
 		CC55A7111E52A0F200594372 /* ASResponderChainEnumerator.h in Headers */ = {isa = PBXBuildFile; fileRef = CC55A70F1E52A0F200594372 /* ASResponderChainEnumerator.h */; };
 		CC55A7121E52A0F200594372 /* ASResponderChainEnumerator.m in Sources */ = {isa = PBXBuildFile; fileRef = CC55A7101E52A0F200594372 /* ASResponderChainEnumerator.m */; };
+		CC56013B1F06E9A700DC4FBE /* ASIntegerMap.h in Headers */ = {isa = PBXBuildFile; fileRef = CC5601391F06E9A700DC4FBE /* ASIntegerMap.h */; };
+		CC56013C1F06E9A700DC4FBE /* ASIntegerMap.mm in Sources */ = {isa = PBXBuildFile; fileRef = CC56013A1F06E9A700DC4FBE /* ASIntegerMap.mm */; };
 		CC57EAF71E3939350034C595 /* ASCollectionView+Undeprecated.h in Headers */ = {isa = PBXBuildFile; fileRef = CC2E317F1DAC353700EEE891 /* ASCollectionView+Undeprecated.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		CC57EAF81E3939450034C595 /* ASTableView+Undeprecated.h in Headers */ = {isa = PBXBuildFile; fileRef = CC512B841DAC45C60054848E /* ASTableView+Undeprecated.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		CC583AD61EF9BDBE00134156 /* ASTestCase.m in Sources */ = {isa = PBXBuildFile; fileRef = CC583AC21EF9BAB400134156 /* ASTestCase.m */; };
@@ -399,6 +401,7 @@
 		CCCCCCE71EC3F0FC0087FE10 /* NSAttributedString+ASText.h in Headers */ = {isa = PBXBuildFile; fileRef = CCCCCCE51EC3F0FC0087FE10 /* NSAttributedString+ASText.h */; };
 		CCCCCCE81EC3F0FC0087FE10 /* NSAttributedString+ASText.m in Sources */ = {isa = PBXBuildFile; fileRef = CCCCCCE61EC3F0FC0087FE10 /* NSAttributedString+ASText.m */; };
 		CCDD148B1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCDD148A1EEDCD9D0020834E /* ASCollectionModernDataSourceTests.m */; };
+		CCE4F9B31F0D60AC00062E4E /* ASIntegerMapTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCE4F9B21F0D60AC00062E4E /* ASIntegerMapTests.m */; };
 		CCF18FF41D2575E300DF5895 /* NSIndexSet+ASHelpers.h in Headers */ = {isa = PBXBuildFile; fileRef = CC4981BA1D1C7F65004E13CC /* NSIndexSet+ASHelpers.h */; settings = {ATTRIBUTES = (Private, ); }; };
 		DB55C2671C641AE4004EDCF5 /* ASContextTransitioning.h in Headers */ = {isa = PBXBuildFile; fileRef = DB55C2651C641AE4004EDCF5 /* ASContextTransitioning.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		DB7121BCD50849C498C886FB /* libPods-AsyncDisplayKitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = EFA731F0396842FF8AB635EE /* libPods-AsyncDisplayKitTests.a */; };
@@ -788,7 +791,7 @@
 		CC11F9791DB181180024D77B /* ASNetworkImageNodeTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASNetworkImageNodeTests.m; sourceTree = "<group>"; };
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 		CC2F65EC1E5FFB1600DA57C9 /* ASMutableElementMap.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASMutableElementMap.h; sourceTree = "<group>"; };
-		CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASMutableElementMap.mm; sourceTree = "<group>"; };
+		CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASMutableElementMap.m; sourceTree = "<group>"; };
 		CC3B20811C3F76D600798563 /* ASPendingStateController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASPendingStateController.h; sourceTree = "<group>"; };
 		CC3B20821C3F76D600798563 /* ASPendingStateController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASPendingStateController.mm; sourceTree = "<group>"; };
 		CC3B20871C3F7A5400798563 /* ASWeakSet.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASWeakSet.h; sourceTree = "<group>"; };
@@ -807,6 +810,8 @@
 		CC55A70C1E529FA200594372 /* UIResponder+AsyncDisplayKit.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "UIResponder+AsyncDisplayKit.m"; sourceTree = "<group>"; };
 		CC55A70F1E52A0F200594372 /* ASResponderChainEnumerator.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASResponderChainEnumerator.h; sourceTree = "<group>"; };
 		CC55A7101E52A0F200594372 /* ASResponderChainEnumerator.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASResponderChainEnumerator.m; sourceTree = "<group>"; };
+		CC5601391F06E9A700DC4FBE /* ASIntegerMap.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASIntegerMap.h; sourceTree = "<group>"; };
+		CC56013A1F06E9A700DC4FBE /* ASIntegerMap.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASIntegerMap.mm; sourceTree = "<group>"; };
 		CC57EAF91E394EA40034C595 /* Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		CC583AC01EF9BAB400134156 /* ASDisplayNode+OCMock.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = "ASDisplayNode+OCMock.m"; sourceTree = "<group>"; };
 		CC583AC11EF9BAB400134156 /* ASTestCase.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = ASTestCase.h; sourceTree = "<group>"; };
@@ -873,6 +878,7 @@
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 		CCE04B211E313EB9006AEBBB /* IGListAdapter+AsyncDisplayKit.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = "IGListAdapter+AsyncDisplayKit.m"; sourceTree = "<group>"; };
 		CCE04B2B1E314A32006AEBBB /* ASSupplementaryNodeSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASSupplementaryNodeSource.h; sourceTree = "<group>"; };
+		CCE4F9B21F0D60AC00062E4E /* ASIntegerMapTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASIntegerMapTests.m; sourceTree = "<group>"; };
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 		D785F6601A74327E00291744 /* ASScrollNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASScrollNode.h; sourceTree = "<group>"; };
 		D785F6611A74327E00291744 /* ASScrollNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASScrollNode.mm; sourceTree = "<group>"; };
@@ -1132,6 +1138,7 @@
 				CC034A0F1E60C9BF00626263 /* ASRectTableTests.m */,
 				CC11F9791DB181180024D77B /* ASNetworkImageNodeTests.m */,
 				CC051F1E1D7A286A006434CB /* ASCALayerTests.m */,
+				CCE4F9B21F0D60AC00062E4E /* ASIntegerMapTests.m */,
 				CC8B05D71D73979700F54286 /* ASTextNodePerformanceTests.m */,
 				CC8B05D41D73836400F54286 /* ASPerformanceTestContext.h */,
 				CC8B05D51D73836400F54286 /* ASPerformanceTestContext.m */,
@@ -1210,6 +1217,8 @@
 		058D09E1195D050800B7D73C /* Details */ = {
 			isa = PBXGroup;
 			children = (
+				CC5601391F06E9A700DC4FBE /* ASIntegerMap.h */,
+				CC56013A1F06E9A700DC4FBE /* ASIntegerMap.mm */,
 				CC0F885E1E4280B800576FED /* _ASCollectionViewCell.h */,
 				CC0F885D1E4280B800576FED /* _ASCollectionViewCell.m */,
 				3917EBD21E9C2FC400D04A01 /* _ASCollectionReusableView.h */,
@@ -1318,7 +1327,7 @@
 				CCA282B21E9EA7310037E8B7 /* ASTipsController.h */,
 				CCA282B31E9EA7310037E8B7 /* ASTipsController.m */,
 				CC2F65EC1E5FFB1600DA57C9 /* ASMutableElementMap.h */,
-				CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.mm */,
+				CC2F65ED1E5FFB1600DA57C9 /* ASMutableElementMap.m */,
 				E5ABAC791E8564EE007AC15C /* ASRectTable.h */,
 				E5ABAC7A1E8564EE007AC15C /* ASRectTable.m */,
 				CC55A70F1E52A0F200594372 /* ASResponderChainEnumerator.h */,
@@ -1713,6 +1722,7 @@
 				509E68631B3AEDB4009B9150 /* ASCollectionViewLayoutController.h in Headers */,
 				B35061F71B010EFD0018CF92 /* ASCollectionViewProtocols.h in Headers */,
 				68FC85E31CE29B7E00EDD713 /* ASTabBarController.h in Headers */,
+				CC56013B1F06E9A700DC4FBE /* ASIntegerMap.h in Headers */,
 				B35061FA1B010EFD0018CF92 /* ASControlNode+Subclasses.h in Headers */,
 				E54E81FC1EB357BD00FFE8E1 /* ASPageTable.h in Headers */,
 				B35061F81B010EFD0018CF92 /* ASControlNode.h in Headers */,
@@ -2089,6 +2099,7 @@
 				69FEE53D1D95A9AF0086F066 /* ASLayoutElementStyleTests.m in Sources */,
 				CC4981B31D1A02BE004E13CC /* ASTableViewThrashTests.m in Sources */,
 				CC54A81E1D7008B300296A24 /* ASDispatchTests.m in Sources */,
+				CCE4F9B31F0D60AC00062E4E /* ASIntegerMapTests.m in Sources */,
 				058D0A3B195D057000B7D73C /* ASDisplayNodeTestsHelper.m in Sources */,
 				83A7D95E1D446A6E00BF333E /* ASWeakMapTests.m in Sources */,
 				056D21551ABCEF50001107EF /* ASImageNodeSnapshotTests.m in Sources */,
@@ -2210,7 +2221,7 @@
 				B350621E1B010EFD0018CF92 /* ASHighlightOverlayLayer.mm in Sources */,
 				9CC606651D24DF9E006581A0 /* NSIndexSet+ASHelpers.m in Sources */,
 				CC0F885F1E4280B800576FED /* _ASCollectionViewCell.m in Sources */,
-				CC2F65EF1E5FFB1600DA57C9 /* ASMutableElementMap.mm in Sources */,
+				CC2F65EF1E5FFB1600DA57C9 /* ASMutableElementMap.m in Sources */,
 				B35062541B010EFD0018CF92 /* ASImageNode+CGExtras.m in Sources */,
 				E58E9E4A1E941DA5004CFC59 /* ASCollectionLayout.mm in Sources */,
 				6947B0C01E36B4E30007C478 /* ASStackUnpositionedLayout.mm in Sources */,
@@ -2279,6 +2290,7 @@
 				254C6B831BF94F8A003EC431 /* ASTextKitCoreTextAdditions.m in Sources */,
 				CCCCCCE21EC3EF060087FE10 /* ASTextUtilities.m in Sources */,
 				CC55A70E1E529FA200594372 /* UIResponder+AsyncDisplayKit.m in Sources */,
+				CC56013C1F06E9A700DC4FBE /* ASIntegerMap.mm in Sources */,
 				697796611D8AC8D3007E93D7 /* ASLayoutSpec+Subclasses.mm in Sources */,
 				B350623B1B010EFD0018CF92 /* NSMutableAttributedString+TextKitAdditions.m in Sources */,
 				CCA282CD1E9EB73E0037E8B7 /* ASTipNode.m in Sources */,

Source/Details/ASDataController.mm

@@ -695,7 +695,7 @@ - (void)_updateElementsInMap:(ASMutableElementMap *)map
   }
 
   // Migrate old supplementary nodes to their new index paths.
-  [map migrateSupplementaryElementsWithChangeSet:changeSet];
+  [map migrateSupplementaryElementsWithSectionMapping:changeSet.sectionMapping];
 
   for (_ASHierarchyItemChange *change in [changeSet itemChangesOfType:_ASHierarchyChangeTypeDelete]) {
     [map removeItemsAtIndexPaths:change.indexPaths];

Source/Details/ASIntegerMap.h

@@ -0,0 +1,70 @@
+//
+//  ASIntegerMap.h
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  All rights reserved.
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+
+#import <Foundation/Foundation.h>
+#import <AsyncDisplayKit/ASBaseDefines.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * An objective-C wrapper for unordered_map.
+ */
+AS_SUBCLASSING_RESTRICTED
+@interface ASIntegerMap : NSObject <NSCopying>
+
+/**
+ * Creates a map based on the specified update to an array.
+ *
+ * If oldCount is 0, returns the empty map.
+ * If deleted and inserted are empty, returns the identity map.
+ */
++ (ASIntegerMap *)mapForUpdateWithOldCount:(NSInteger)oldCount
+                                   deleted:(nullable NSIndexSet *)deleted
+                                  inserted:(nullable NSIndexSet *)inserted;
+
+/**
+ * A singleton that maps each integer to itself. Its inverse is itself.
+ *
+ * Note: You cannot mutate this.
+ */
+@property (class, atomic, readonly) ASIntegerMap *identityMap;
+
+/**
+ * A singleton that returns NSNotFound for all keys. Its inverse is itself.
+ *
+ * Note: You cannot mutate this.
+ */
+@property (class, atomic, readonly) ASIntegerMap *emptyMap;
+
+/**
+ * Retrieves the integer for a given key, or NSNotFound if the key is not found.
+ *
+ * @param key A key to lookup the value for.
+ */
+- (NSInteger)integerForKey:(NSInteger)key;
+
+/**
+ * Sets the value for a given key.
+ *
+ * @param value The new value.
+ * @param key The key to store the value for.
+ */
+- (void)setInteger:(NSInteger)value forKey:(NSInteger)key;
+
+/**
+ * Create and return a map with the inverse mapping.
+ */
+- (ASIntegerMap *)inverseMap;
+
+@end
+
+NS_ASSUME_NONNULL_END

Source/Details/ASIntegerMap.mm

@@ -0,0 +1,188 @@
+//
+//  ASIntegerMap.mm
+//  Texture
+//
+//  Copyright (c) 2017-present, Pinterest, Inc.  All rights reserved.
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+
+#import "ASIntegerMap.h"
+#import <AsyncDisplayKit/ASAssert.h>
+#import <unordered_map>
+#import <NSIndexSet+ASHelpers.h>
+#import <AsyncDisplayKit/ASObjectDescriptionHelpers.h>
+
+/**
+ * This is just a friendly Objective-C interface to unordered_map<NSInteger, NSInteger>
+ */
+@interface ASIntegerMap () <ASDescriptionProvider>
+@end
+
+@implementation ASIntegerMap {
+  std::unordered_map<NSInteger, NSInteger> _map;
+  BOOL _isIdentity;
+  BOOL _isEmpty;
+  BOOL _immutable; // identity map and empty mape are immutable.
+}
+
+#pragma mark - Singleton
+
++ (ASIntegerMap *)identityMap
+{
+  static ASIntegerMap *identityMap;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    identityMap = [[ASIntegerMap alloc] init];
+    identityMap->_isIdentity = YES;
+    identityMap->_immutable = YES;
+  });
+  return identityMap;
+}
+
++ (ASIntegerMap *)emptyMap
+{
+  static ASIntegerMap *emptyMap;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    emptyMap = [[ASIntegerMap alloc] init];
+    emptyMap->_isEmpty = YES;
+    emptyMap->_immutable = YES;
+  });
+  return emptyMap;
+}
+
++ (ASIntegerMap *)mapForUpdateWithOldCount:(NSInteger)oldCount deleted:(NSIndexSet *)deletions inserted:(NSIndexSet *)insertions
+{
+  if (oldCount == 0) {
+    return ASIntegerMap.emptyMap;
+  }
+
+  if (deletions.count == 0 && insertions.count == 0) {
+    return ASIntegerMap.identityMap;
+  }
+
+  ASIntegerMap *result = [[ASIntegerMap alloc] init];
+  // Start with the old indexes
+  NSMutableIndexSet *indexes = [NSMutableIndexSet indexSetWithIndexesInRange:NSMakeRange(0, oldCount)];
+
+  // Descending order, shift deleted ranges left
+  [deletions enumerateRangesWithOptions:NSEnumerationReverse usingBlock:^(NSRange range, BOOL * _Nonnull stop) {
+    [indexes shiftIndexesStartingAtIndex:NSMaxRange(range) by:-range.length];
+  }];
+
+  // Ascending order, shift inserted ranges right
+  [insertions enumerateRangesUsingBlock:^(NSRange range, BOOL * _Nonnull stop) {
+    [indexes shiftIndexesStartingAtIndex:range.location by:range.length];
+  }];
+
+  __block NSInteger oldIndex = 0;
+  [indexes enumerateRangesUsingBlock:^(NSRange range, BOOL * _Nonnull stop) {
+    // Note we advance oldIndex unconditionally, not newIndex
+    for (NSInteger newIndex = range.location; newIndex < NSMaxRange(range); oldIndex++) {
+      if ([deletions containsIndex:oldIndex]) {
+        // index was deleted, do nothing, just let oldIndex advance.
+      } else {
+        // assign the next index for this item.
+        result->_map[oldIndex] = newIndex++;
+      }
+    }
+  }];
+  return result;
+}
+
+- (NSInteger)integerForKey:(NSInteger)key
+{
+  if (_isIdentity) {
+    return key;
+  } else if (_isEmpty) {
+    return NSNotFound;
+  }
+
+  auto result = _map.find(key);
+  return result != _map.end() ? result->second : NSNotFound;
+}
+
+- (void)setInteger:(NSInteger)value forKey:(NSInteger)key
+{
+  if (_immutable) {
+    ASDisplayNodeFailAssert(@"Cannot mutate special integer map: %@", self);
+    return;
+  }
+
+  _map[key] = value;
+}
+
+- (ASIntegerMap *)inverseMap
+{
+  if (_isIdentity || _isEmpty) {
+    return self;
+  }
+
+  auto result = [[ASIntegerMap alloc] init];
+  for (auto it = _map.begin(); it != _map.end(); it++) {
+    result->_map[it->second] = it->first;
+  }
+  return result;
+}
+
+#pragma mark - NSCopying
+
+- (id)copyWithZone:(NSZone *)zone
+{
+  if (_immutable) {
+    return self;
+  }
+
+  auto newMap = [[ASIntegerMap allocWithZone:zone] init];
+  newMap->_map = _map;
+  return newMap;
+}
+
+#pragma mark - Description
+
+- (NSMutableArray<NSDictionary *> *)propertiesForDescription
+{
+  NSMutableArray *result = [NSMutableArray array];
+
+  if (_isIdentity) {
+    [result addObject:@{ @"map": @"<identity>" }];
+  } else if (_isEmpty) {
+    [result addObject:@{ @"map": @"<empty>" }];
+  } else {
+    // { 1->2 3->4 5->6 }
+    NSMutableString *str = [NSMutableString string];
+    for (auto it = _map.begin(); it != _map.end(); it++) {
+      [str appendFormat:@" %zd->%zd", it->first, it->second];
+    }
+    // Remove leading space
+    if (str.length > 0) {
+      [str deleteCharactersInRange:NSMakeRange(0, 1)];
+    }
+    [result addObject:@{ @"map": str }];
+  }
+
+  return result;
+}
+
+- (NSString *)description
+{
+  return ASObjectDescriptionMakeWithoutObject([self propertiesForDescription]);
+}
+
+- (BOOL)isEqual:(id)object
+{
+  if ([super isEqual:object]) {
+    return YES;
+  }
+
+  if (auto otherMap = ASDynamicCast(object, ASIntegerMap)) {
+    return otherMap->_map == _map;
+  }
+  return NO;
+}
+
+@end

Source/Private/ASMutableElementMap.h

@@ -18,6 +18,7 @@
 #import <Foundation/Foundation.h>
 #import <AsyncDisplayKit/ASBaseDefines.h>
 #import <AsyncDisplayKit/ASElementMap.h>
+#import <AsyncDisplayKit/ASIntegerMap.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -57,7 +58,7 @@ AS_SUBCLASSING_RESTRICTED
  *
  * This also deletes any supplementary elements in deleted sections.
  */
-- (void)migrateSupplementaryElementsWithChangeSet:(_ASHierarchyChangeSet *)changeSet;
+- (void)migrateSupplementaryElementsWithSectionMapping:(ASIntegerMap *)mapping;
 
 @end