Make Cell Node Properties Atomic (#74)

* Make ASCellNode indexPath and supplementaryElementKind atomic

* Update the change log

* Fix licenses

* Be explicit with atomic

* Rename the protocol

* And the file

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -368,6 +368,7 @@
 		CCA282D01E9EBF6C0037E8B7 /* ASTipsWindow.h in Headers */ = {isa = PBXBuildFile; fileRef = CCA282CE1E9EBF6C0037E8B7 /* ASTipsWindow.h */; };
 		CCA282D11E9EBF6C0037E8B7 /* ASTipsWindow.m in Sources */ = {isa = PBXBuildFile; fileRef = CCA282CF1E9EBF6C0037E8B7 /* ASTipsWindow.m */; };
 		CCB2F34D1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m in Sources */ = {isa = PBXBuildFile; fileRef = CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */; };
+		CCBBBF5D1EB161760069AA91 /* ASRangeManagingNode.h in Headers */ = {isa = PBXBuildFile; fileRef = CCBBBF5C1EB161760069AA91 /* ASRangeManagingNode.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		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 */; };
@@ -798,6 +799,7 @@
 		CCA282CE1E9EBF6C0037E8B7 /* ASTipsWindow.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASTipsWindow.h; sourceTree = "<group>"; };
 		CCA282CF1E9EBF6C0037E8B7 /* ASTipsWindow.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASTipsWindow.m; sourceTree = "<group>"; };
 		CCB2F34C1D63CCC6004E6DE9 /* ASDisplayNodeSnapshotTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDisplayNodeSnapshotTests.m; sourceTree = "<group>"; };
+		CCBBBF5C1EB161760069AA91 /* ASRangeManagingNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASRangeManagingNode.h; sourceTree = "<group>"; };
 		CCBD05DE1E4147B000D18509 /* ASIGListAdapterBasedDataSource.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASIGListAdapterBasedDataSource.m; sourceTree = "<group>"; };
 		CCBD05DF1E4147B000D18509 /* ASIGListAdapterBasedDataSource.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASIGListAdapterBasedDataSource.h; sourceTree = "<group>"; };
 		CCE04B1E1E313EA7006AEBBB /* ASSectionController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASSectionController.h; sourceTree = "<group>"; };
@@ -1002,6 +1004,7 @@
 				25E327551C16819500A2170C /* ASPagerNode.m */,
 				A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */,
 				A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */,
+				CCBBBF5C1EB161760069AA91 /* ASRangeManagingNode.h */,
 				ACE87A2B1D73696800D7FF06 /* ASSectionContext.h */,
 				D785F6601A74327E00291744 /* ASScrollNode.h */,
 				D785F6611A74327E00291744 /* ASScrollNode.mm */,
@@ -1533,6 +1536,7 @@
 				509E68611B3AEDA0009B9150 /* ASAbstractLayoutController.h in Headers */,
 				CCA282B81E9EA8E40037E8B7 /* AsyncDisplayKit+Tips.h in Headers */,
 				B35062571B010F070018CF92 /* ASAssert.h in Headers */,
+				CCBBBF5D1EB161760069AA91 /* ASRangeManagingNode.h in Headers */,
 				B35062581B010F070018CF92 /* ASAvailability.h in Headers */,
 				DE84918D1C8FFF2B003D89E9 /* ASRunLoopQueue.h in Headers */,
 				CC0F88621E4281E200576FED /* ASSectionController.h in Headers */,

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Fix `__has_include` check in ASLog.h [Philipp Smorygo](Philipp.Smorygo@jetbrains.com)
 - Fix potential deadlock in ASControlNode [Garrett Moon](https://github.com/garrettmoon)
 - [Yoga Beta] Improvements to the experimental support for Yoga layout [Scott Goodson](appleguy)
+- Make cell node `indexPath` and `supplementaryElementKind` atomic so you can read from any thread. (Adlai-Holler)[https://github.com/Adlai-Holler] (#49)[https://github.com/TextureGroup/Texture/pull/74]
 - Update the rasterization API and un-deprecate it. [Adlai Holler](https://github.com/Adlai-Holler)[#82](https://github.com/TextureGroup/Texture/pull/49)
 - Simplified & optimized hashing code. [Adlai Holler](https://github.com/Adlai-Holler) [#86](https://github.com/TextureGroup/Texture/pull/86)
 - Improve the performance & safety of ASDisplayNode subnodes. [Adlai Holler](https://github.com/Adlai-Holler) [#223](https://github.com/TextureGroup/Texture/pull/223)

Source/ASCellNode.h

@@ -20,6 +20,7 @@
 NS_ASSUME_NONNULL_BEGIN
 
 @class ASCellNode, ASTextNode;
+@protocol ASRangeManagingNode;
 
 typedef NSUInteger ASCellNodeAnimation;
 
@@ -87,7 +88,7 @@ typedef NS_ENUM(NSUInteger, ASCellNodeVisibilityEvent) {
  * @return The supplementary element kind, or @c nil if this node does not represent a supplementary element.
  */
 //TODO change this to be a generic "kind" or "elementKind" that exposes `nil` for row kind
-@property (nonatomic, copy, readonly, nullable) NSString *supplementaryElementKind;
+@property (atomic, copy, readonly, nullable) NSString *supplementaryElementKind;
 
 /*
  * The layout attributes currently assigned to this node, if any.
@@ -113,10 +114,8 @@ typedef NS_ENUM(NSUInteger, ASCellNodeVisibilityEvent) {
 /**
  * The current index path of this cell node, or @c nil if this node is
  * not a valid item inside a table node or collection node.
- *
- * @note This property must be accessed on the main thread.
  */
-@property (nonatomic, readonly, nullable) NSIndexPath *indexPath;
+@property (atomic, readonly, nullable) NSIndexPath *indexPath;
 
 /**
  * The backing view controller, or @c nil if the node wasn't initialized with backing view controller
@@ -126,10 +125,9 @@ typedef NS_ENUM(NSUInteger, ASCellNodeVisibilityEvent) {
 
 
 /**
- * The owning node (ASCollectionNode/ASTableNode) of this cell node, or @c nil if this node is
+ * The table- or collection-node that this cell is a member of, if any.
- * not a valid item inside a table node or collection node or if those nodes are nil.
  */
-@property (weak, nonatomic, readonly, nullable) ASDisplayNode *owningNode;
+@property (atomic, weak, readonly, nullable) id<ASRangeManagingNode> owningNode;
 
 /*
  * ASCellNode must forward touch events in order for UITableView and UICollectionView tap handling to work. Overriding

Source/ASCellNode.mm

@@ -44,12 +44,6 @@
   ASDisplayNode *_viewControllerNode;
   UIViewController *_viewController;
   BOOL _suspendInteractionDelegate;
-
-  struct {
-    unsigned int isTableNode:1;
-    unsigned int isCollectionNode:1;
-  } _owningNodeType;
-
 }
 
 @end
@@ -165,19 +159,6 @@
   }
 }
 
-- (void)setOwningNode:(ASDisplayNode *)owningNode
-{
-  _owningNode = owningNode;
-
-  memset(&_owningNodeType, 0, sizeof(_owningNodeType));
-
-  if ([owningNode isKindOfClass:[ASTableNode class]]) {
-    _owningNodeType.isTableNode      = 1;
-  } else if ([owningNode isKindOfClass:[ASCollectionNode class]]) {
-    _owningNodeType.isCollectionNode = 1;
-  }
-}
-
 - (void)__setSelectedFromUIKit:(BOOL)selected;
 {
   if (selected != _selected) {
@@ -198,15 +179,7 @@
 
 - (NSIndexPath *)indexPath
 {
-  ASDisplayNodeAssertMainThread();
+  return [self.owningNode indexPathForNode:self];
-
-  if (_owningNodeType.isTableNode) {
-    return [(ASTableNode *)self.owningNode indexPathForNode:self];
-  } else if (_owningNodeType.isCollectionNode) {
-    return [(ASCollectionNode *)self.owningNode indexPathForNode:self];
-  }
-
-  return nil;
 }
 
 - (UIViewController *)viewController

Source/ASCollectionNode.h

@@ -20,6 +20,7 @@
 #import <AsyncDisplayKit/ASRangeControllerUpdateRangeProtocol+Beta.h>
 #import <AsyncDisplayKit/ASCollectionView.h>
 #import <AsyncDisplayKit/ASBlockTypes.h>
+#import <AsyncDisplayKit/ASRangeManagingNode.h>
 
 @protocol ASCollectionViewLayoutFacilitatorProtocol;
 @protocol ASCollectionDelegate;
@@ -32,7 +33,7 @@ NS_ASSUME_NONNULL_BEGIN
  * ASCollectionNode is a node based class that wraps an ASCollectionView. It can be used
  * as a subnode of another node, and provide room for many (great) features and improvements later on.
  */
-@interface ASCollectionNode : ASDisplayNode <ASRangeControllerUpdateRangeProtocol>
+@interface ASCollectionNode : ASDisplayNode <ASRangeControllerUpdateRangeProtocol, ASRangeManagingNode>
 
 - (instancetype)init NS_UNAVAILABLE;
 

Source/ASCollectionNode.mm

@@ -155,7 +155,7 @@
     __weak __typeof__(self) weakSelf = self;
     [self setViewBlock:^{
       __typeof__(self) strongSelf = weakSelf;
-      return [[[strongSelf collectionViewClass] alloc] _initWithFrame:frame collectionViewLayout:strongSelf->_pendingState.collectionViewLayout layoutFacilitator:layoutFacilitator eventLog:ASDisplayNodeGetEventLog(strongSelf)];
+      return [[[strongSelf collectionViewClass] alloc] _initWithFrame:frame collectionViewLayout:strongSelf->_pendingState.collectionViewLayout layoutFacilitator:layoutFacilitator owningNode:strongSelf eventLog:ASDisplayNodeGetEventLog(strongSelf)];
     }];
   }
   return self;

Source/ASCollectionView.mm

@@ -80,7 +80,7 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 #pragma mark -
 #pragma mark ASCollectionView.
 
-@interface ASCollectionView () <ASRangeControllerDataSource, ASRangeControllerDelegate, ASDataControllerSource, ASCellNodeInteractionDelegate, ASDelegateProxyInterceptor, ASBatchFetchingScrollView, ASDataControllerEnvironmentDelegate, ASCALayerExtendedDelegate, UICollectionViewDelegateFlowLayout> {
+@interface ASCollectionView () <ASRangeControllerDataSource, ASRangeControllerDelegate, ASDataControllerSource, ASCellNodeInteractionDelegate, ASDelegateProxyInterceptor, ASBatchFetchingScrollView, ASCALayerExtendedDelegate, UICollectionViewDelegateFlowLayout> {
   ASCollectionViewProxy *_proxyDataSource;
   ASCollectionViewProxy *_proxyDelegate;
   
@@ -250,10 +250,10 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
 
 - (instancetype)initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout
 {
-  return [self _initWithFrame:frame collectionViewLayout:layout layoutFacilitator:nil eventLog:nil];
+  return [self _initWithFrame:frame collectionViewLayout:layout layoutFacilitator:nil owningNode:nil eventLog:nil];
 }
 
-- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator eventLog:(ASEventLog *)eventLog
+- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator owningNode:(ASCollectionNode *)owningNode eventLog:(ASEventLog *)eventLog
 {
   if (!(self = [super initWithFrame:frame collectionViewLayout:layout]))
     return nil;
@@ -273,9 +273,8 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   _rangeController.delegate = self;
   _rangeController.layoutController = _layoutController;
   
-  _dataController = [[ASDataController alloc] initWithDataSource:self eventLog:eventLog];
+  _dataController = [[ASDataController alloc] initWithDataSource:self node:owningNode eventLog:eventLog];
   _dataController.delegate = _rangeController;
-  _dataController.environmentDelegate = self;
   
   _batchContext = [[ASBatchContext alloc] init];
   
@@ -1649,11 +1648,6 @@ static NSString * const kReuseIdentifier = @"_ASCollectionReuseIdentifier";
   
 }
 
-- (id<ASTraitEnvironment>)dataControllerEnvironment
-{
-  return self.collectionNode;
-}
-
 #pragma mark - ASDataControllerSource optional methods
 
 - (ASCellNodeBlock)dataController:(ASDataController *)dataController supplementaryNodeBlockOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath

Source/ASRangeManagingNode.h

@@ -0,0 +1,35 @@
+//
+//  ASRangeManagingNode.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/ASTraitCollection.h>
+
+@class ASCellNode;
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * Basically ASTableNode or ASCollectionNode.
+ */
+@protocol ASRangeManagingNode <NSObject, ASTraitEnvironment>
+
+/**
+ * Retrieve the index path for the given node, if it's a member of this container.
+ *
+ * @param node The node.
+ * @return The index path, or nil if the node is not part of this container.
+ */
+- (nullable NSIndexPath *)indexPathForNode:(ASCellNode *)node;
+
+@end
+
+NS_ASSUME_NONNULL_END

Source/ASTableNode.h

@@ -19,7 +19,7 @@
 #import <AsyncDisplayKit/ASDisplayNode.h>
 #import <AsyncDisplayKit/ASRangeControllerUpdateRangeProtocol+Beta.h>
 #import <AsyncDisplayKit/ASTableView.h>
-
+#import <AsyncDisplayKit/ASRangeManagingNode.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -31,7 +31,7 @@ NS_ASSUME_NONNULL_BEGIN
  * ASTableNode is a node based class that wraps an ASTableView. It can be used
  * as a subnode of another node, and provide room for many (great) features and improvements later on.
  */
-@interface ASTableNode : ASDisplayNode <ASRangeControllerUpdateRangeProtocol>
+@interface ASTableNode : ASDisplayNode <ASRangeControllerUpdateRangeProtocol, ASRangeManagingNode>
 
 - (instancetype)init; // UITableViewStylePlain
 - (instancetype)initWithStyle:(UITableViewStyle)style NS_DESIGNATED_INITIALIZER;

Source/ASTableNode.mm

@@ -80,7 +80,7 @@
     [self setViewBlock:^{
       // Variable will be unused if event logging is off.
       __unused __typeof__(self) strongSelf = weakSelf;
-      return [[ASTableView alloc] _initWithFrame:CGRectZero style:style dataControllerClass:nil eventLog:ASDisplayNodeGetEventLog(strongSelf)];
+      return [[ASTableView alloc] _initWithFrame:CGRectZero style:style dataControllerClass:nil owningNode:strongSelf eventLog:ASDisplayNodeGetEventLog(strongSelf)];
     }];
   }
   return self;

Source/ASTableView.mm

@@ -147,7 +147,7 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
 #pragma mark -
 #pragma mark ASTableView
 
-@interface ASTableView () <ASRangeControllerDataSource, ASRangeControllerDelegate, ASDataControllerSource, _ASTableViewCellDelegate, ASCellNodeInteractionDelegate, ASDelegateProxyInterceptor, ASBatchFetchingScrollView, ASDataControllerEnvironmentDelegate>
+@interface ASTableView () <ASRangeControllerDataSource, ASRangeControllerDelegate, ASDataControllerSource, _ASTableViewCellDelegate, ASCellNodeInteractionDelegate, ASDelegateProxyInterceptor, ASBatchFetchingScrollView>
 {
   ASTableViewProxy *_proxyDataSource;
   ASTableViewProxy *_proxyDelegate;
@@ -286,8 +286,22 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
 #pragma mark -
 #pragma mark Lifecycle
 
-- (void)configureWithDataControllerClass:(Class)dataControllerClass eventLog:(ASEventLog *)eventLog
+- (instancetype)initWithFrame:(CGRect)frame style:(UITableViewStyle)style
 {
+  return [self _initWithFrame:frame style:style dataControllerClass:nil owningNode:nil eventLog:nil];
+}
+
+- (instancetype)_initWithFrame:(CGRect)frame style:(UITableViewStyle)style dataControllerClass:(Class)dataControllerClass owningNode:(ASTableNode *)tableNode eventLog:(ASEventLog *)eventLog
+{
+  if (!(self = [super initWithFrame:frame style:style])) {
+    return nil;
+  }
+  _cellsForVisibilityUpdates = [NSMutableSet set];
+  _cellsForLayoutUpdates = [NSMutableSet set];
+  if (!dataControllerClass) {
+    dataControllerClass = [[self class] dataControllerClass];
+  }
+  
   _layoutController = [[ASTableLayoutController alloc] initWithTableView:self];
   
   _rangeController = [[ASRangeController alloc] init];
@@ -295,13 +309,12 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   _rangeController.dataSource = self;
   _rangeController.delegate = self;
   
-  _dataController = [[dataControllerClass alloc] initWithDataSource:self eventLog:eventLog];
+  _dataController = [[dataControllerClass alloc] initWithDataSource:self node:tableNode eventLog:eventLog];
   _dataController.delegate = _rangeController;
-  _dataController.environmentDelegate = self;
+  
-
   _leadingScreensForBatching = 2.0;
   _batchContext = [[ASBatchContext alloc] init];
-
+  
   _automaticallyAdjustsContentOffset = NO;
   
   _nodesConstrainedWidth = self.bounds.size.width;
@@ -313,25 +326,6 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   super.dataSource = (id<UITableViewDataSource>)_proxyDataSource;
   
   [self registerClass:_ASTableViewCell.class forCellReuseIdentifier:kCellReuseIdentifier];
-}
-
-- (instancetype)initWithFrame:(CGRect)frame style:(UITableViewStyle)style
-{
-  return [self _initWithFrame:frame style:style dataControllerClass:nil eventLog:nil];
-}
-
-- (instancetype)_initWithFrame:(CGRect)frame style:(UITableViewStyle)style dataControllerClass:(Class)dataControllerClass eventLog:(ASEventLog *)eventLog
-{
-  if (!(self = [super initWithFrame:frame style:style])) {
-    return nil;
-  }
-  _cellsForVisibilityUpdates = [NSMutableSet set];
-  _cellsForLayoutUpdates = [NSMutableSet set];
-  if (!dataControllerClass) {
-    dataControllerClass = [[self class] dataControllerClass];
-  }
-  
-  [self configureWithDataControllerClass:dataControllerClass eventLog:eventLog];
   
   if (!AS_AT_LEAST_IOS9) {
     _retainedLayer = self.layer;
@@ -1734,13 +1728,6 @@ static NSString * const kCellReuseIdentifier = @"_ASTableViewCell";
   return (fabs(rect.size.height - size.height) < FLT_EPSILON);
 }
 
-#pragma mark - ASDataControllerEnvironmentDelegate
-
-- (id<ASTraitEnvironment>)dataControllerEnvironment
-{
-  return self.tableNode;
-}
-
 #pragma mark - _ASTableViewCellDelegate
 
 - (void)didLayoutSubviewsOfTableViewCell:(_ASTableViewCell *)tableViewCell

Source/ASTableViewInternal.h

@@ -40,7 +40,7 @@
  *
  * @param eventLog An event log passed through to the data controller.
  */
-- (instancetype)_initWithFrame:(CGRect)frame style:(UITableViewStyle)style dataControllerClass:(Class)dataControllerClass eventLog:(ASEventLog *)eventLog;
+- (instancetype)_initWithFrame:(CGRect)frame style:(UITableViewStyle)style dataControllerClass:(Class)dataControllerClass owningNode:(ASTableNode *)tableNode eventLog:(ASEventLog *)eventLog;
 
 /// Set YES and we'll log every time we call [super insertRows…] etc
 @property (nonatomic) BOOL test_enableSuperUpdateCallLogging;

Source/AsyncDisplayKit.h

@@ -43,6 +43,7 @@
 #import <AsyncDisplayKit/ASCollectionViewLayoutInspector.h>
 #import <AsyncDisplayKit/ASCollectionViewLayoutFacilitatorProtocol.h>
 #import <AsyncDisplayKit/ASCellNode.h>
+#import <AsyncDisplayKit/ASRangeManagingNode.h>
 #import <AsyncDisplayKit/ASSectionContext.h>
 
 #import <AsyncDisplayKit/ASElementMap.h>

Source/Details/ASCollectionElement.h

@@ -19,6 +19,7 @@
 #import <AsyncDisplayKit/ASTraitCollection.h>
 
 @class ASDisplayNode;
+@protocol ASRangeManagingNode;
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -28,13 +29,13 @@ AS_SUBCLASSING_RESTRICTED
 //TODO change this to be a generic "kind" or "elementKind" that exposes `nil` for row kind
 @property (nonatomic, readonly, copy, nullable) NSString *supplementaryElementKind;
 @property (nonatomic, assign) ASSizeRange constrainedSize;
-@property (nonatomic, weak) ASDisplayNode *owningNode;
+@property (nonatomic, readonly, weak) id<ASRangeManagingNode> owningNode;
 @property (nonatomic, assign) ASPrimitiveTraitCollection traitCollection;
 
 - (instancetype)initWithNodeBlock:(ASCellNodeBlock)nodeBlock
          supplementaryElementKind:(nullable NSString *)supplementaryElementKind
                   constrainedSize:(ASSizeRange)constrainedSize
-                       owningNode:(ASDisplayNode *)owningNode
+                       owningNode:(id<ASRangeManagingNode>)owningNode
                   traitCollection:(ASPrimitiveTraitCollection)traitCollection;
 
 /**

Source/Details/ASCollectionElement.mm

@@ -34,7 +34,7 @@
 - (instancetype)initWithNodeBlock:(ASCellNodeBlock)nodeBlock
          supplementaryElementKind:(NSString *)supplementaryElementKind
                   constrainedSize:(ASSizeRange)constrainedSize
-                       owningNode:(ASDisplayNode *)owningNode
+                       owningNode:(id<ASRangeManagingNode>)owningNode
                   traitCollection:(ASPrimitiveTraitCollection)traitCollection
 {
   NSAssert(nodeBlock != nil, @"Node block must not be nil");

Source/Details/ASCollectionInternal.h

@@ -25,7 +25,7 @@ NS_ASSUME_NONNULL_BEGIN
 @class ASRangeController;
 
 @interface ASCollectionView ()
-- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(nullable id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator eventLog:(nullable ASEventLog *)eventLog;
+- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(nullable id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator owningNode:(nullable ASCollectionNode *)owningNode eventLog:(nullable ASEventLog *)eventLog;
 
 @property (nonatomic, weak, readwrite) ASCollectionNode *collectionNode;
 @property (nonatomic, strong, readonly) ASDataController *dataController;

Source/Details/ASDataController.h

@@ -39,6 +39,7 @@ NS_ASSUME_NONNULL_BEGIN
 @class ASElementMap;
 @class ASLayout;
 @class _ASHierarchyChangeSet;
+@protocol ASRangeManagingNode;
 @protocol ASTraitEnvironment;
 @protocol ASSectionContext;
 
@@ -96,12 +97,6 @@ extern NSString * const ASCollectionInvalidUpdateException;
 
 @end
 
-@protocol ASDataControllerEnvironmentDelegate
-
-- (nullable id<ASTraitEnvironment>)dataControllerEnvironment;
-
-@end
-
 /**
  Delegate for notify the data updating of data controller.
  These methods will be invoked from main thread right now, but it may be moved to background thread in the future.
@@ -160,17 +155,30 @@ extern NSString * const ASCollectionInvalidUpdateException;
  */
 @interface ASDataController : NSObject
 
-- (instancetype)initWithDataSource:(id<ASDataControllerSource>)dataSource eventLog:(nullable ASEventLog *)eventLog NS_DESIGNATED_INITIALIZER;
+- (instancetype)initWithDataSource:(id<ASDataControllerSource>)dataSource node:(nullable id<ASRangeManagingNode>)node eventLog:(nullable ASEventLog *)eventLog NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+/**
+ * The node that owns this data controller, if any.
+ *
+ * NOTE: Soon we will drop support for using ASTableView/ASCollectionView without the node, so this will be non-null.
+ */
+@property (nonatomic, nullable, weak, readonly) id<ASRangeManagingNode> node;
 
 /**
  * The map that is currently displayed. The "UIKit index space."
+ *
+ * This property will only be changed on the main thread.
  */
-@property (nonatomic, strong, readonly) ASElementMap *visibleMap;
+@property (atomic, copy, readonly) ASElementMap *visibleMap;
 
 /**
  * The latest map fetched from the data source. May be more recent than @c visibleMap.
+ *
+ * This property will only be changed on the main thread.
  */
-@property (nonatomic, strong, readonly) ASElementMap *pendingMap;
+@property (atomic, copy, readonly) ASElementMap *pendingMap;
 
 /**
  Data source for fetching data info.
@@ -187,11 +195,6 @@ extern NSString * const ASCollectionInvalidUpdateException;
  */
 @property (nonatomic, weak) id<ASDataControllerDelegate> delegate;
 
-/**
- *
- */
-@property (nonatomic, weak) id<ASDataControllerEnvironmentDelegate> environmentDelegate;
-
 /**
  * Delegate for preparing layouts. Main thead only.
  */

Source/Details/ASDataController.mm

@@ -27,6 +27,7 @@
 #import <AsyncDisplayKit/ASLayout.h>
 #import <AsyncDisplayKit/ASMainSerialQueue.h>
 #import <AsyncDisplayKit/ASMutableElementMap.h>
+#import <AsyncDisplayKit/ASRangeManagingNode.h>
 #import <AsyncDisplayKit/ASThread.h>
 #import <AsyncDisplayKit/ASTwoDimensionalArrayUtils.h>
 #import <AsyncDisplayKit/ASSection.h>
@@ -85,18 +86,21 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   } _dataSourceFlags;
 }
 
+@property (atomic, copy, readwrite) ASElementMap *pendingMap;
+@property (atomic, copy, readwrite) ASElementMap *visibleMap;
 @end
 
 @implementation ASDataController
 
 #pragma mark - Lifecycle
 
-- (instancetype)initWithDataSource:(id<ASDataControllerSource>)dataSource eventLog:(ASEventLog *)eventLog
+- (instancetype)initWithDataSource:(id<ASDataControllerSource>)dataSource node:(nullable id<ASRangeManagingNode>)node eventLog:(ASEventLog *)eventLog
 {
   if (!(self = [super init])) {
     return nil;
   }
   
+  _node = node;
   _dataSource = dataSource;
   
   _dataSourceFlags.supplementaryNodeKindsInSections = [_dataSource respondsToSelector:@selector(dataController:supplementaryNodeKindsInSections:)];
@@ -110,7 +114,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   _eventLog = eventLog;
 #endif
 
-  _visibleMap = _pendingMap = [[ASElementMap alloc] init];
+  self.visibleMap = self.pendingMap = [[ASElementMap alloc] init];
   
   _nextSectionID = 0;
   
@@ -124,14 +128,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   return self;
 }
 
-- (instancetype)init
-{
-  ASDisplayNodeFailAssert(@"Failed to call designated initializer.");
-  id<ASDataControllerSource> fakeDataSource = nil;
-  ASEventLog *eventLog = nil;
-  return [self initWithDataSource:fakeDataSource eventLog:eventLog];
-}
-
 + (NSUInteger)parallelProcessorCount
 {
   static NSUInteger parallelProcessorCount;
@@ -277,9 +273,10 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
       }
     }];
   } else if (_dataSourceFlags.supplementaryNodesOfKindInSection) {
+    id<ASDataControllerSource> dataSource = _dataSource;
     [sections enumerateRangesUsingBlock:^(NSRange range, BOOL * _Nonnull stop) {
       for (NSUInteger sectionIndex = range.location; sectionIndex < NSMaxRange(range); sectionIndex++) {
-        NSUInteger itemCount = [_dataSource dataController:self supplementaryNodesOfKind:kind inSection:sectionIndex];
+        NSUInteger itemCount = [dataSource dataController:self supplementaryNodesOfKind:kind inSection:sectionIndex];
         for (NSUInteger i = 0; i < itemCount; i++) {
           [indexPaths addObject:[NSIndexPath indexPathForItem:i inSection:sectionIndex]];
         }
@@ -296,7 +293,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
  * @param map The element map into which to apply the change.
  * @param indexPaths The index paths belongs to sections whose supplementary nodes need to be repopulated.
  * @param changeSet The changeset that triggered this repopulation.
- * @param owningNode The node that owns the new elements.
  * @param traitCollection The trait collection needed to initialize elements
  * @param indexPathsAreNew YES if index paths are "after the update," NO otherwise.
  * @param shouldFetchSizeRanges Whether constrained sizes should be fetched from data source
@@ -304,7 +300,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 - (void)_repopulateSupplementaryNodesIntoMap:(ASMutableElementMap *)map
              forSectionsContainingIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
                                    changeSet:(_ASHierarchyChangeSet *)changeSet
-                                  owningNode:(ASDisplayNode *)owningNode
                              traitCollection:(ASPrimitiveTraitCollection)traitCollection
                             indexPathsAreNew:(BOOL)indexPathsAreNew
                        shouldFetchSizeRanges:(BOOL)shouldFetchSizeRanges
@@ -330,7 +325,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   }
 
   for (NSString *kind in [self supplementaryKindsInSections:newSections]) {
-    [self _insertElementsIntoMap:map kind:kind forSections:newSections owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+    [self _insertElementsIntoMap:map kind:kind forSections:newSections traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
   }
 }
 
@@ -346,7 +341,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 - (void)_insertElementsIntoMap:(ASMutableElementMap *)map
                           kind:(NSString *)kind
                    forSections:(NSIndexSet *)sections
-                    owningNode:(ASDisplayNode *)owningNode
                traitCollection:(ASPrimitiveTraitCollection)traitCollection
          shouldFetchSizeRanges:(BOOL)shouldFetchSizeRanges
 {
@@ -357,7 +351,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   }
   
   NSArray<NSIndexPath *> *indexPaths = [self _allIndexPathsForItemsOfKind:kind inSections:sections];
-  [self _insertElementsIntoMap:map kind:kind atIndexPaths:indexPaths owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+  [self _insertElementsIntoMap:map kind:kind atIndexPaths:indexPaths traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
 }
 
 /**
@@ -373,7 +367,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 - (void)_insertElementsIntoMap:(ASMutableElementMap *)map
                           kind:(NSString *)kind
                   atIndexPaths:(NSArray<NSIndexPath *> *)indexPaths
-                    owningNode:(ASDisplayNode *)owningNode
                traitCollection:(ASPrimitiveTraitCollection)traitCollection
          shouldFetchSizeRanges:(BOOL)shouldFetchSizeRanges
 {
@@ -390,12 +383,14 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   }
   
   LOG(@"Populating elements of kind: %@, for index paths: %@", kind, indexPaths);
+  id<ASDataControllerSource> dataSource = self.dataSource;
+  id<ASRangeManagingNode> node = self.node;
   for (NSIndexPath *indexPath in indexPaths) {
     ASCellNodeBlock nodeBlock;
     if (isRowKind) {
-      nodeBlock = [_dataSource dataController:self nodeBlockAtIndexPath:indexPath];
+      nodeBlock = [dataSource dataController:self nodeBlockAtIndexPath:indexPath];
     } else {
-      nodeBlock = [_dataSource dataController:self supplementaryNodeBlockOfKind:kind atIndexPath:indexPath];
+      nodeBlock = [dataSource dataController:self supplementaryNodeBlockOfKind:kind atIndexPath:indexPath];
     }
     
     ASSizeRange constrainedSize;
@@ -406,7 +401,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
     ASCollectionElement *element = [[ASCollectionElement alloc] initWithNodeBlock:nodeBlock
                                                          supplementaryElementKind:isRowKind ? nil : kind
                                                                   constrainedSize:constrainedSize
-                                                                       owningNode:owningNode
+                                                                       owningNode:node
                                                                   traitCollection:traitCollection];
     [map insertElement:element atIndexPath:indexPath];
   }
@@ -544,14 +539,12 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 
   // Step 1: Update the mutable copies to match the data source's state
   [self _updateSectionContextsInMap:mutableMap changeSet:changeSet];
-  __weak id<ASTraitEnvironment> environment = [self.environmentDelegate dataControllerEnvironment];
+  ASPrimitiveTraitCollection existingTraitCollection = [self.node primitiveTraitCollection];
-  __weak ASDisplayNode *owningNode = (ASDisplayNode *)environment; // This is gross!
+  [self _updateElementsInMap:mutableMap changeSet:changeSet traitCollection:existingTraitCollection shouldFetchSizeRanges:(! canDelegateLayout)];
-  ASPrimitiveTraitCollection existingTraitCollection = [environment primitiveTraitCollection];
-  [self _updateElementsInMap:mutableMap changeSet:changeSet owningNode:owningNode traitCollection:existingTraitCollection shouldFetchSizeRanges:(! canDelegateLayout)];
   
   // Step 2: Clone the new data
   ASElementMap *newMap = [mutableMap copy];
-  _pendingMap = newMap;
+  self.pendingMap = newMap;
   
   // Step 3: Ask layout delegate for contexts
   id layoutContext = nil;
@@ -585,7 +578,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
         [_delegate dataController:self willUpdateWithChangeSet:changeSet];
 
         // Step 5: Deploy the new data as "completed" and inform delegate
-        _visibleMap = newMap;
+        self.visibleMap = newMap;
         
         [_delegate dataController:self didUpdateWithChangeSet:changeSet];
       }];
@@ -644,7 +637,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
  */
 - (void)_updateElementsInMap:(ASMutableElementMap *)map
                    changeSet:(_ASHierarchyChangeSet *)changeSet
-                  owningNode:(ASDisplayNode *)owningNode
              traitCollection:(ASPrimitiveTraitCollection)traitCollection
        shouldFetchSizeRanges:(BOOL)shouldFetchSizeRanges
 {
@@ -656,7 +648,7 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
     NSUInteger sectionCount = [self itemCountsFromDataSource].size();
     if (sectionCount > 0) {
       NSIndexSet *sectionIndexes = [NSIndexSet indexSetWithIndexesInRange:NSMakeRange(0, sectionCount)];
-      [self _insertElementsIntoMap:map sections:sectionIndexes owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+      [self _insertElementsIntoMap:map sections:sectionIndexes traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
     }
     // Return immediately because reloadData can't be used in conjuntion with other updates.
     return;
@@ -667,7 +659,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
     // Aggressively repopulate supplementary nodes (#1773 & #1629)
     [self _repopulateSupplementaryNodesIntoMap:map forSectionsContainingIndexPaths:change.indexPaths
                                      changeSet:changeSet
-                                    owningNode:owningNode
                                traitCollection:traitCollection
                               indexPathsAreNew:NO
                          shouldFetchSizeRanges:shouldFetchSizeRanges];
@@ -680,15 +671,14 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
   }
   
   for (_ASHierarchySectionChange *change in [changeSet sectionChangesOfType:_ASHierarchyChangeTypeInsert]) {
-    [self _insertElementsIntoMap:map sections:change.indexSet owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+    [self _insertElementsIntoMap:map sections:change.indexSet traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
   }
   
   for (_ASHierarchyItemChange *change in [changeSet itemChangesOfType:_ASHierarchyChangeTypeInsert]) {
-    [self _insertElementsIntoMap:map kind:ASDataControllerRowNodeKind atIndexPaths:change.indexPaths owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+    [self _insertElementsIntoMap:map kind:ASDataControllerRowNodeKind atIndexPaths:change.indexPaths traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
     // Aggressively reload supplementary nodes (#1773 & #1629)
     [self _repopulateSupplementaryNodesIntoMap:map forSectionsContainingIndexPaths:change.indexPaths
                                      changeSet:changeSet
-                                    owningNode:owningNode
                                traitCollection:traitCollection
                               indexPathsAreNew:YES
                          shouldFetchSizeRanges:shouldFetchSizeRanges];
@@ -697,7 +687,6 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 
 - (void)_insertElementsIntoMap:(ASMutableElementMap *)map
                       sections:(NSIndexSet *)sectionIndexes
-                    owningNode:(ASDisplayNode *)owningNode
                traitCollection:(ASPrimitiveTraitCollection)traitCollection
          shouldFetchSizeRanges:(BOOL)shouldFetchSizeRanges
 {
@@ -709,12 +698,12 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 
   // Items
   [map insertEmptySectionsOfItemsAtIndexes:sectionIndexes];
-  [self _insertElementsIntoMap:map kind:ASDataControllerRowNodeKind forSections:sectionIndexes owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+  [self _insertElementsIntoMap:map kind:ASDataControllerRowNodeKind forSections:sectionIndexes traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
 
   // Supplementaries
   for (NSString *kind in [self supplementaryKindsInSections:sectionIndexes]) {
     // Step 2: Populate new elements for all sections
-    [self _insertElementsIntoMap:map kind:kind forSections:sectionIndexes owningNode:owningNode traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
+    [self _insertElementsIntoMap:map kind:kind forSections:sectionIndexes traitCollection:traitCollection shouldFetchSizeRanges:shouldFetchSizeRanges];
   }
 }
 
@@ -729,10 +718,11 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
     return;
   }
   
+  id<ASDataControllerSource> dataSource = self.dataSource;
   for (ASCellNode *node in nodes) {
     ASSizeRange constrainedSize = [self constrainedSizeForElement:node.collectionElement inElementMap:_pendingMap];
     [self _layoutNode:node withConstrainedSize:constrainedSize];
-    BOOL matchesSize = [_dataSource dataController:self presentedSizeForElement:node.collectionElement matchesSize:node.frame.size];
+    BOOL matchesSize = [dataSource dataController:self presentedSizeForElement:node.collectionElement matchesSize:node.frame.size];
     if (! matchesSize) {
       [nodesSizesChanged addObject:node];
     }
@@ -783,8 +773,9 @@ typedef void (^ASDataControllerCompletionBlock)(NSArray<ASCollectionElement *> *
 
     // Can't update the trait collection right away because _visibleMap may not be up-to-date,
     // i.e there might be some elements that were allocated using the old trait collection but haven't been added to _visibleMap
+    
     [self _scheduleBlockOnMainSerialQueue:^{
-      ASPrimitiveTraitCollection newTraitCollection = [[_environmentDelegate dataControllerEnvironment] primitiveTraitCollection];
+      ASPrimitiveTraitCollection newTraitCollection = [self.node primitiveTraitCollection];
       for (ASCollectionElement *element in _visibleMap) {
         element.traitCollection = newTraitCollection;
       }

Source/Private/ASCellNode+Internal.h

@@ -72,9 +72,9 @@ NS_ASSUME_NONNULL_BEGIN
  */
 @property (nonatomic, strong, nullable) UICollectionViewLayoutAttributes *layoutAttributes;
 
-@property (weak, nullable) ASCollectionElement *collectionElement;
+@property (atomic, weak, nullable) ASCollectionElement *collectionElement;
 
-@property (nonatomic, weak, nullable) ASDisplayNode *owningNode;
+@property (atomic, weak, nullable) id<ASRangeManagingNode> owningNode;
 
 @property (nonatomic, assign) BOOL shouldUseUIKitCell;
 

Tests/ASTableViewTests.mm

@@ -1,5 +1,5 @@
 //
-//  ASTableViewTests.m
+//  ASTableViewTests.mm
 //  Texture
 //
 //  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
@@ -61,7 +61,7 @@
 - (instancetype)__initWithFrame:(CGRect)frame style:(UITableViewStyle)style
 {
   
-  return [super _initWithFrame:frame style:style dataControllerClass:[ASTestDataController class] eventLog:nil];
+  return [super _initWithFrame:frame style:style dataControllerClass:[ASTestDataController class] owningNode:nil eventLog:nil];
 }
 
 - (ASTestDataController *)testDataController