From e8ce7fcbb2ab6cc2c0b4825cd756dd7ee2a43103 Mon Sep 17 00:00:00 2001
From: Levi McCallum <levi.mccallum@nfl.com>
Date: Wed, 21 Oct 2015 23:14:54 -0700
Subject: [PATCH] Clean up caching of collection view delegate selectors on the
 inspector

---
 AsyncDisplayKit/ASCollectionView.mm                    |  2 +-
 .../Details/ASCollectionViewFlowLayoutInspector.h      | 10 ++++++++--
 .../Details/ASCollectionViewFlowLayoutInspector.m      |  7 +++----
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/AsyncDisplayKit/ASCollectionView.mm b/AsyncDisplayKit/ASCollectionView.mm
index 08f4b435..01b4927a 100644
--- a/AsyncDisplayKit/ASCollectionView.mm
+++ b/AsyncDisplayKit/ASCollectionView.mm
@@ -334,7 +334,7 @@ static BOOL _isInterceptedSelector(SEL sel)
     _asyncDelegateImplementsInsetSection = ([_asyncDelegate respondsToSelector:@selector(collectionView:layout:insetForSectionAtIndex:)] ? 1 : 0);
   }
 
-  [_flowLayoutInspector cacheSelectorsForCollectionView:self];
+  [_layoutInspector didChangeCollectionViewDelegate:asyncDelegate];
 }
 
 - (void)setCollectionViewLayout:(UICollectionViewLayout *)collectionViewLayout
diff --git a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.h b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.h
index 5aab03e0..179b8808 100644
--- a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.h
+++ b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.h
@@ -11,6 +11,7 @@
 #import <AsyncDisplayKit/ASDimension.h>
 
 @class ASCollectionView;
+@protocol ASCollectionViewDelegate;
 
 @protocol ASCollectionViewLayoutInspecting <NSObject>
 
@@ -29,6 +30,13 @@
  */
 - (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:(id<ASCollectionViewDelegate>)delegate;
+
 @end
 
 @interface ASCollectionViewFlowLayoutInspector : NSObject <ASCollectionViewLayoutInspecting>
@@ -37,6 +45,4 @@
 
 - (instancetype)initWithCollectionView:(ASCollectionView *)collectionView flowLayout:(UICollectionViewFlowLayout *)flowLayout;
 
-- (void)cacheSelectorsForCollectionView:(ASCollectionView *)collectionView;
-
 @end
diff --git a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
index beb654d0..e90cd461 100644
--- a/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
+++ b/AsyncDisplayKit/Details/ASCollectionViewFlowLayoutInspector.m
@@ -30,19 +30,18 @@
   }
 
   if (self != nil) {
-    [self cacheSelectorsForCollectionView:collectionView];
+    [self didChangeCollectionViewDelegate:collectionView.asyncDelegate];
     _layout = flowLayout;
   }
   return self;
 }
 
-- (void)cacheSelectorsForCollectionView:(ASCollectionView *)collectionView
+- (void)didChangeCollectionViewDelegate:(id<ASCollectionViewDelegate>)delegate;
 {
-  if (collectionView == nil) {
+  if (delegate == nil) {
     _delegateImplementsReferenceSizeForHeader = nil;
     _delegateImplementsReferenceSizeForFooter = nil;
   } else {
-    id<ASCollectionViewDelegateFlowLayout> delegate = [self delegateForCollectionView:collectionView];
     _delegateImplementsReferenceSizeForHeader = [delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForHeaderInSection:)];
     _delegateImplementsReferenceSizeForFooter = [delegate respondsToSelector:@selector(collectionView:layout:referenceSizeForFooterInSection:)];
   }