[ASCollectionView] Move ASCollectionViewLayoutInspector to its own file

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -185,6 +185,9 @@
 		68B8A4E21CBDB958007E4543 /* ASWeakProxy.h in Headers */ = {isa = PBXBuildFile; fileRef = 68B8A4DF1CBDB958007E4543 /* ASWeakProxy.h */; };
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 		68B8A4E41CBDB958007E4543 /* ASWeakProxy.m in Sources */ = {isa = PBXBuildFile; fileRef = 68B8A4E01CBDB958007E4543 /* ASWeakProxy.m */; };
+		68C215581DE10D330019C4BC /* ASCollectionViewLayoutInspector.h in Headers */ = {isa = PBXBuildFile; fileRef = 68C215561DE10D330019C4BC /* ASCollectionViewLayoutInspector.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		68C215591DE10D330019C4BC /* ASCollectionViewLayoutInspector.m in Sources */ = {isa = PBXBuildFile; fileRef = 68C215571DE10D330019C4BC /* ASCollectionViewLayoutInspector.m */; };
+		68C2155A1DE10D330019C4BC /* ASCollectionViewLayoutInspector.m in Sources */ = {isa = PBXBuildFile; fileRef = 68C215571DE10D330019C4BC /* ASCollectionViewLayoutInspector.m */; };
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@@ -992,6 +995,8 @@
 		68B8A4DB1CBD911D007E4543 /* ASImageNode+AnimatedImagePrivate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = "ASImageNode+AnimatedImagePrivate.h"; sourceTree = "<group>"; };
 		68B8A4DF1CBDB958007E4543 /* ASWeakProxy.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASWeakProxy.h; sourceTree = "<group>"; };
 		68B8A4E01CBDB958007E4543 /* ASWeakProxy.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASWeakProxy.m; sourceTree = "<group>"; };
+		68C215561DE10D330019C4BC /* ASCollectionViewLayoutInspector.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASCollectionViewLayoutInspector.h; sourceTree = "<group>"; };
+		68C215571DE10D330019C4BC /* ASCollectionViewLayoutInspector.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASCollectionViewLayoutInspector.m; sourceTree = "<group>"; };
 		68EE0DBB1C1B4ED300BA1B99 /* ASMainSerialQueue.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASMainSerialQueue.h; sourceTree = "<group>"; };
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 		68FC85DC1CE29AB700EDD713 /* ASNavigationController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASNavigationController.h; sourceTree = "<group>"; };
@@ -1493,6 +1498,8 @@
 				054963481A1EA066000F8E56 /* ASBasicImageDownloader.mm */,
 				299DA1A71A828D2900162D41 /* ASBatchContext.h */,
 				299DA1A81A828D2900162D41 /* ASBatchContext.mm */,
+				68C215561DE10D330019C4BC /* ASCollectionViewLayoutInspector.h */,
+				68C215571DE10D330019C4BC /* ASCollectionViewLayoutInspector.m */,
 				251B8EF41BBB3D690087C538 /* ASCollectionViewFlowLayoutInspector.h */,
 				251B8EF51BBB3D690087C538 /* ASCollectionViewFlowLayoutInspector.m */,
 				205F0E1B1B373A2C007741D0 /* ASCollectionViewLayoutController.h */,
@@ -1822,6 +1829,7 @@
 				DE89C1741DCEB9CC00D49D74 /* ASLayoutElementInspectorNode.h in Headers */,
 				B13CA1011C52004900E031AB /* ASCollectionNode+Beta.h in Headers */,
 				254C6B7E1BF94DF4003EC431 /* ASTextKitTailTruncater.h in Headers */,
+				68C215581DE10D330019C4BC /* ASCollectionViewLayoutInspector.h in Headers */,
 				B35062411B010EFD0018CF92 /* _ASAsyncTransactionGroup.h in Headers */,
 				B35062491B010EFD0018CF92 /* _ASCoreAnimationExtras.h in Headers */,
 				B350620F1B010EFD0018CF92 /* _ASDisplayLayer.h in Headers */,
@@ -2018,12 +2026,15 @@
 			isa = PBXNativeTarget;
 			buildConfigurationList = 058D09D2195D04C000B7D73C /* Build configuration list for PBXNativeTarget "AsyncDisplayKitTests" */;
 			buildPhases = (
+				A5D6EC8A55F2AA9E9EE68B07 /* 📦 Check Pods Manifest.lock */,
 				2E61B6A0DB0F436A9DDBE86F /* [CP] Check Pods Manifest.lock */,
 				058D09B8195D04C000B7D73C /* Sources */,
 				058D09B9195D04C000B7D73C /* Frameworks */,
 				058D09BA195D04C000B7D73C /* Resources */,
 				3B9D88CDF51B429C8409E4B6 /* [CP] Copy Pods Resources */,
 				B130AB1AC0A1E5162E211C19 /* [CP] Embed Pods Frameworks */,
+				3BFEAD5C584653624B1B9F75 /* 📦 Embed Pods Frameworks */,
+				2F77738278748228F6400335 /* 📦 Copy Pods Resources */,
 			);
 			buildRules = (
 			);
@@ -2139,6 +2150,21 @@
 			shellScript = "diff \"${PODS_ROOT}/../Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [[ $? != 0 ]] ; then\n    cat << EOM\nerror: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\nEOM\n    exit 1\nfi\n";
 			showEnvVarsInLog = 0;
 		};
+		2F77738278748228F6400335 /* 📦 Copy Pods Resources */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "📦 Copy Pods Resources";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests-resources.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
 		3B9D88CDF51B429C8409E4B6 /* [CP] Copy Pods Resources */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
@@ -2154,6 +2180,36 @@
 			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests-resources.sh\"\n";
 			showEnvVarsInLog = 0;
 		};
+		3BFEAD5C584653624B1B9F75 /* 📦 Embed Pods Frameworks */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "📦 Embed Pods Frameworks";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods-AsyncDisplayKitTests/Pods-AsyncDisplayKitTests-frameworks.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
+		A5D6EC8A55F2AA9E9EE68B07 /* 📦 Check Pods Manifest.lock */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputPaths = (
+			);
+			name = "📦 Check Pods Manifest.lock";
+			outputPaths = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "diff \"${PODS_ROOT}/../Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [[ $? != 0 ]] ; then\n    cat << EOM\nerror: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\nEOM\n    exit 1\nfi\n";
+			showEnvVarsInLog = 0;
+		};
 		B130AB1AC0A1E5162E211C19 /* [CP] Embed Pods Frameworks */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
@@ -2296,6 +2352,7 @@
 				ACF6ED321B17843500DA7C62 /* ASAbsoluteLayoutSpec.mm in Sources */,
 				AC026B6B1BD57D6F00BBC17E /* ASChangeSetDataController.mm in Sources */,
 				68355B311CB5799E001D4E68 /* ASImageNode+AnimatedImage.mm in Sources */,
+				68C215591DE10D330019C4BC /* ASCollectionViewLayoutInspector.m in Sources */,
 				9CFFC6C01CCAC73C006A6476 /* ASViewController.mm in Sources */,
 				055F1A3519ABD3E3004DAFF1 /* ASTableView.mm in Sources */,
 				6959433E1D70815300B0EE1F /* ASDisplayNodeLayout.mm in Sources */,
@@ -2486,6 +2543,7 @@
 				AC026B6C1BD57D6F00BBC17E /* ASChangeSetDataController.mm in Sources */,
 				34EFC7741B701D0A00AD841F /* ASAbsoluteLayoutSpec.mm in Sources */,
 				92074A6A1CC8BADA00918F75 /* ASControlNode+tvOS.m in Sources */,
+				68C2155A1DE10D330019C4BC /* ASCollectionViewLayoutInspector.m in Sources */,
 				DB78412E1C6BCE1600A9E2B4 /* _ASTransitionContext.m in Sources */,
 				B350620B1B010EFD0018CF92 /* ASTableView.mm in Sources */,
 				B350620E1B010EFD0018CF92 /* ASTextNode.mm in Sources */,

AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.h

@@ -10,78 +10,10 @@
 
 #pragma once
 
-#import <Foundation/Foundation.h>
+#include "ASCollectionViewLayoutInspector.h"
-#import <AsyncDisplayKit/ASDimension.h>
-#import <AsyncDisplayKit/ASScrollDirection.h>
-
-@class ASCollectionView;
-@protocol ASCollectionDataSource;
-@protocol ASCollectionDelegate;
 
 NS_ASSUME_NONNULL_BEGIN
 
-@protocol ASCollectionViewLayoutInspecting <NSObject>
-
-/**
- * Asks the inspector to provide a constrained size range for the given collection view node.
- */
-- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath;
-
-/**
- * Return the directions in which your collection view can scroll
- */
-- (ASScrollDirection)scrollableDirections;
-
-@optional
-
-/**
- * Asks the inspector to provide a constrained size range for the given supplementary node.
- */
-- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
-
-/**
- * Asks the inspector for the number of supplementary views for the given kind in the specified section.
- */
-- (NSUInteger)collectionView:(ASCollectionView *)collectionView supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section;
-
-/**
- * Allow the inspector to respond to delegate changes.
- *
- * @discussion A great time to update perform selector caches!
- */
-- (void)didChangeCollectionViewDelegate:(nullable id<ASCollectionDelegate>)delegate;
-
-/**
- * Allow the inspector to respond to dataSource changes.
- *
- * @discussion A great time to update perform selector caches!
- */
-- (void)didChangeCollectionViewDataSource:(nullable id<ASCollectionDataSource>)dataSource;
-
-#pragma mark Deprecated Methods
-
-/**
- * Asks the inspector for the number of supplementary sections in the collection view for the given kind.
- *
- * @deprecated This method will not be called, and it is only deprecated as a reminder to remove it.
- * Supplementary elements must exist in the same sections as regular collection view items i.e. -numberOfSectionsInCollectionView:
- */
-- (NSUInteger)collectionView:(ASCollectionView *)collectionView numberOfSectionsForSupplementaryNodeOfKind:(NSString *)kind ASDISPLAYNODE_DEPRECATED_MSG("Use ASCollectionNode's method instead.");
-
-@end
-
-/**
- * A layout inspector for non-flow layouts that returns a constrained size to let the cells layout itself as
- * far as possible based on the scrollable direction of the collection view. It throws exceptions for delegate
- * methods that are related to supplementary node's management.
- */
-@interface ASCollectionViewLayoutInspector : NSObject <ASCollectionViewLayoutInspecting>
-
-- (instancetype)init NS_UNAVAILABLE;
-- (instancetype)initWithCollectionView:(ASCollectionView *)collectionView NS_DESIGNATED_INITIALIZER;
-
-@end
-
 /**
  * A layout inspector implementation specific for the sizing behavior of UICollectionViewFlowLayouts
  */

AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m

@@ -16,90 +16,6 @@
 
 #define kDefaultItemSize CGSizeMake(50, 50)
 
-#pragma mark - Helper Functions
-
-// Returns a constrained size to let the cells layout itself as far as possible based on the scrollable direction
-// of the collection view
-static inline ASSizeRange NodeConstrainedSizeForScrollDirection(ASCollectionView *collectionView) {
-  CGSize maxSize = collectionView.bounds.size;
-  if (ASScrollDirectionContainsHorizontalDirection(collectionView.scrollableDirections)) {
-    maxSize.width = CGFLOAT_MAX;
-  } else {
-    maxSize.height = CGFLOAT_MAX;
-  }
-  return ASSizeRangeMake(CGSizeZero, maxSize);
-}
-
-#pragma mark - ASCollectionViewLayoutInspector
-
-@implementation ASCollectionViewLayoutInspector {
-  struct {
-    unsigned int implementsConstrainedSizeForNodeAtIndexPathDeprecated:1;
-    unsigned int implementsConstrainedSizeForNodeAtIndexPath:1;
-  } _delegateFlags;
-}
-
-#pragma mark Lifecycle
-
-- (instancetype)initWithCollectionView:(ASCollectionView *)collectionView
-{
-  self = [super init];
-  if (self != nil) {
-    [self didChangeCollectionViewDelegate:collectionView.asyncDelegate];
-  }
-  return self;
-}
-
-#pragma mark ASCollectionViewLayoutInspecting
-
-- (void)didChangeCollectionViewDelegate:(id<ASCollectionDelegate>)delegate
-{
-  if (delegate == nil) {
-    memset(&_delegateFlags, 0, sizeof(_delegateFlags));
-  } else {
-    _delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated = [delegate respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)];
-    _delegateFlags.implementsConstrainedSizeForNodeAtIndexPath = [delegate respondsToSelector:@selector(collectionNode:constrainedSizeForItemAtIndexPath:)];
-  }
-}
-
-- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
-{
-  if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPath) {
-    return [collectionView.asyncDelegate collectionNode:collectionView.collectionNode constrainedSizeForItemAtIndexPath:indexPath];
-  } else if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated) {
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wdeprecated-declarations"
-    return [collectionView.asyncDelegate collectionView:collectionView constrainedSizeForNodeAtIndexPath:indexPath];
-#pragma clang diagnostic pop
-  } else {
-    // With 2.0 `collectionView:constrainedSizeForNodeAtIndexPath:` was moved to the delegate. Assert if not implemented on the delegate but on the data source
-    ASDisplayNodeAssert([collectionView.asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)] == NO, @"collectionView:constrainedSizeForNodeAtIndexPath: was moved from the ASCollectionDataSource to the ASCollectionDelegate.");
-  }
-  
-  return NodeConstrainedSizeForScrollDirection(collectionView);
-}
-
-- (ASScrollDirection)scrollableDirections
-{
-  ASDisplayNodeAssert(NO, @"layoutInspector object must implement -scrollableDirections %@", self);
-  return ASScrollDirectionNone;
-}
-
-- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
-{
-  ASDisplayNodeAssert(NO, @"To support supplementary nodes in ASCollectionView, it must have a layoutInspector for layout inspection. (See ASCollectionViewFlowLayoutInspector for an example.)");
-  return ASSizeRangeMake(CGSizeZero, CGSizeZero);
-}
-
-- (NSUInteger)collectionView:(ASCollectionView *)collectionView supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section
-{
-  ASDisplayNodeAssert(NO, @"To support supplementary nodes in ASCollectionView, it must have a layoutInspector for layout inspection. (See ASCollectionViewFlowLayoutInspector for an example.)");
-  return 0;
-}
-
-@end
-
-
 #pragma mark - ASCollectionViewFlowLayoutInspector
 
 @interface ASCollectionViewFlowLayoutInspector ()

AsyncDisplayKit/Details/ASCollectionViewLayoutInspector.h

@@ -0,0 +1,83 @@
+//
+//  ASCollectionViewLayoutInspector.h
+//  AsyncDisplayKit
+//
+//  Created by Garrett Moon on 11/19/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+#import <AsyncDisplayKit/ASDimension.h>
+#import <AsyncDisplayKit/ASScrollDirection.h>
+
+@class ASCollectionView;
+@protocol ASCollectionDataSource;
+@protocol ASCollectionDelegate;
+
+NS_ASSUME_NONNULL_BEGIN
+
+extern ASSizeRange NodeConstrainedSizeForScrollDirection(ASCollectionView *collectionView);
+
+@protocol ASCollectionViewLayoutInspecting <NSObject>
+
+/**
+ * Asks the inspector to provide a constrained size range for the given collection view node.
+ */
+- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath;
+
+/**
+ * Return the directions in which your collection view can scroll
+ */
+- (ASScrollDirection)scrollableDirections;
+
+@optional
+
+/**
+ * Asks the inspector to provide a constrained size range for the given supplementary node.
+ */
+- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath;
+
+/**
+ * Asks the inspector for the number of supplementary views for the given kind in the specified section.
+ */
+- (NSUInteger)collectionView:(ASCollectionView *)collectionView supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section;
+
+/**
+ * Allow the inspector to respond to delegate changes.
+ *
+ * @discussion A great time to update perform selector caches!
+ */
+- (void)didChangeCollectionViewDelegate:(nullable id<ASCollectionDelegate>)delegate;
+
+/**
+ * Allow the inspector to respond to dataSource changes.
+ *
+ * @discussion A great time to update perform selector caches!
+ */
+- (void)didChangeCollectionViewDataSource:(nullable id<ASCollectionDataSource>)dataSource;
+
+#pragma mark Deprecated Methods
+
+/**
+ * Asks the inspector for the number of supplementary sections in the collection view for the given kind.
+ *
+ * @deprecated This method will not be called, and it is only deprecated as a reminder to remove it.
+ * Supplementary elements must exist in the same sections as regular collection view items i.e. -numberOfSectionsInCollectionView:
+ */
+- (NSUInteger)collectionView:(ASCollectionView *)collectionView numberOfSectionsForSupplementaryNodeOfKind:(NSString *)kind ASDISPLAYNODE_DEPRECATED_MSG("Use ASCollectionNode's method instead.");
+
+@end
+
+/**
+ * A layout inspector for non-flow layouts that returns a constrained size to let the cells layout itself as
+ * far as possible based on the scrollable direction of the collection view. It throws exceptions for delegate
+ * methods that are related to supplementary node's management.
+ */
+@interface ASCollectionViewLayoutInspector : NSObject <ASCollectionViewLayoutInspecting>
+
+- (instancetype)init NS_UNAVAILABLE;
+- (instancetype)initWithCollectionView:(ASCollectionView *)collectionView NS_DESIGNATED_INITIALIZER;
+
+@end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/Details/ASCollectionViewLayoutInspector.m

@@ -0,0 +1,95 @@
+//
+//  ASCollectionViewLayoutInspector.m
+//  AsyncDisplayKit
+//
+//  Created by Garrett Moon on 11/19/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+#import "ASCollectionViewLayoutInspector.h"
+
+#import "ASCollectionView.h"
+#import "ASCollectionView+Undeprecated.h"
+
+#pragma mark - Helper Functions
+
+// Returns a constrained size to let the cells layout itself as far as possible based on the scrollable direction
+// of the collection view
+ASSizeRange NodeConstrainedSizeForScrollDirection(ASCollectionView *collectionView) {
+  CGSize maxSize = collectionView.bounds.size;
+  if (ASScrollDirectionContainsHorizontalDirection(collectionView.scrollableDirections)) {
+    maxSize.width = CGFLOAT_MAX;
+  } else {
+    maxSize.height = CGFLOAT_MAX;
+  }
+  return ASSizeRangeMake(CGSizeZero, maxSize);
+}
+
+#pragma mark - ASCollectionViewLayoutInspector
+
+@implementation ASCollectionViewLayoutInspector {
+  struct {
+    unsigned int implementsConstrainedSizeForNodeAtIndexPathDeprecated:1;
+    unsigned int implementsConstrainedSizeForNodeAtIndexPath:1;
+  } _delegateFlags;
+}
+
+#pragma mark Lifecycle
+
+- (instancetype)initWithCollectionView:(ASCollectionView *)collectionView
+{
+  self = [super init];
+  if (self != nil) {
+    [self didChangeCollectionViewDelegate:collectionView.asyncDelegate];
+  }
+  return self;
+}
+
+#pragma mark ASCollectionViewLayoutInspecting
+
+- (void)didChangeCollectionViewDelegate:(id<ASCollectionDelegate>)delegate
+{
+  if (delegate == nil) {
+    memset(&_delegateFlags, 0, sizeof(_delegateFlags));
+  } else {
+    _delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated = [delegate respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)];
+    _delegateFlags.implementsConstrainedSizeForNodeAtIndexPath = [delegate respondsToSelector:@selector(collectionNode:constrainedSizeForItemAtIndexPath:)];
+  }
+}
+
+- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForNodeAtIndexPath:(NSIndexPath *)indexPath
+{
+  if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPath) {
+    return [collectionView.asyncDelegate collectionNode:collectionView.collectionNode constrainedSizeForItemAtIndexPath:indexPath];
+  } else if (_delegateFlags.implementsConstrainedSizeForNodeAtIndexPathDeprecated) {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+    return [collectionView.asyncDelegate collectionView:collectionView constrainedSizeForNodeAtIndexPath:indexPath];
+#pragma clang diagnostic pop
+  } else {
+    // With 2.0 `collectionView:constrainedSizeForNodeAtIndexPath:` was moved to the delegate. Assert if not implemented on the delegate but on the data source
+    ASDisplayNodeAssert([collectionView.asyncDataSource respondsToSelector:@selector(collectionView:constrainedSizeForNodeAtIndexPath:)] == NO, @"collectionView:constrainedSizeForNodeAtIndexPath: was moved from the ASCollectionDataSource to the ASCollectionDelegate.");
+  }
+  
+  return NodeConstrainedSizeForScrollDirection(collectionView);
+}
+
+- (ASScrollDirection)scrollableDirections
+{
+  ASDisplayNodeAssert(NO, @"layoutInspector object must implement -scrollableDirections %@", self);
+  return ASScrollDirectionNone;
+}
+
+- (ASSizeRange)collectionView:(ASCollectionView *)collectionView constrainedSizeForSupplementaryNodeOfKind:(NSString *)kind atIndexPath:(NSIndexPath *)indexPath
+{
+  ASDisplayNodeAssert(NO, @"To support supplementary nodes in ASCollectionView, it must have a layoutInspector for layout inspection. (See ASCollectionViewFlowLayoutInspector for an example.)");
+  return ASSizeRangeMake(CGSizeZero, CGSizeZero);
+}
+
+- (NSUInteger)collectionView:(ASCollectionView *)collectionView supplementaryNodesOfKind:(NSString *)kind inSection:(NSUInteger)section
+{
+  ASDisplayNodeAssert(NO, @"To support supplementary nodes in ASCollectionView, it must have a layoutInspector for layout inspection. (See ASCollectionViewFlowLayoutInspector for an example.)");
+  return 0;
+}
+
+@end