From 4383e9ab2bf03ad100ddd17507a86e37217a2815 Mon Sep 17 00:00:00 2001
From: Ryan Fitzgerald <ryan.fitz1@gmail.com>
Date: Thu, 9 Jul 2015 12:31:32 -0400
Subject: [PATCH] releasing downloaded image when multiplex image node exits
 render range

---
 AsyncDisplayKit/ASMultiplexImageNode.mm | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/AsyncDisplayKit/ASMultiplexImageNode.mm b/AsyncDisplayKit/ASMultiplexImageNode.mm
index 0bc9c6e8f8..d32d3be061 100644
--- a/AsyncDisplayKit/ASMultiplexImageNode.mm
+++ b/AsyncDisplayKit/ASMultiplexImageNode.mm
@@ -139,6 +139,13 @@ typedef void(^ASMultiplexImageLoadCompletionBlock)(UIImage *image, id imageIdent
  */
 - (void)_downloadImageWithIdentifier:(id)imageIdentifier URL:(NSURL *)imageURL completion:(void (^)(UIImage *image, NSError *error))completionBlock;
 
+/**
+ @abstract Returns a Boolean value indicating whether the downloaded image should be removed when clearing fetched data
+ @discussion Downloaded image data should only be cleared out if a cache is present
+ @return YES if an image cache is available; otherwise, NO.
+ */
+- (BOOL)_shouldClearFetchedImageData;
+
 @end
 
 @implementation ASMultiplexImageNode
@@ -173,11 +180,15 @@ typedef void(^ASMultiplexImageLoadCompletionBlock)(UIImage *image, id imageIdent
   }
 }
 
-- (void)displayWillStart
+- (void)clearFetchedData
 {
-  [super displayWillStart];
-
-  [self fetchData];
+  [super clearFetchedData];
+    
+  if ([self _shouldClearFetchedImageData]) {
+    // setting this to nil makes the node fetch images the next time its display starts
+    _loadedImageIdentifier = nil;
+    self.image = nil;
+  }
 }
 
 - (void)fetchData
@@ -626,4 +637,8 @@ typedef void(^ASMultiplexImageLoadCompletionBlock)(UIImage *image, id imageIdent
     [self _loadNextImage];
 }
 
+- (BOOL)_shouldClearFetchedImageData {
+  return _cache != nil;
+}
+
 @end