[ASDisplayNode] Deprecate -displayWillStart in favor of -displayWillStartAsynchronously: (#536)

* Deprecate -[ASDisplayNode displayWillStart] in favor of -displayWillStartAsynchronously:

* Minor change

* Fix CHANGELOG

* Update CHANGELOG.md

* Update CHANGELOG.md

CHANGELOG.md

@@ -8,7 +8,7 @@
 - Add -[ASDisplayNode detailedLayoutDescription] property to aid debugging. [Adlai Holler](https://github.com/Adlai-Holler) [#476](https://github.com/TextureGroup/Texture/pull/476)
 - Fix an issue that causes calculatedLayoutDidChange being called needlessly. [Huy Nguyen](https://github.com/nguyenhuy) [#490](https://github.com/TextureGroup/Texture/pull/490)
 - Negate iOS 11 automatic estimated table row heights. [Christian Selig](https://github.com/christianselig) [#485](https://github.com/TextureGroup/Texture/pull/485)
-- [Breaking] Add content offset bridging property to ASTableNode and ASCollectionNode. Deprecate related methods in ASTableView and ASCollectionView [Huy Nguyen](https://github.com/nguyenhuy) [#460](https://github.com/TextureGroup/Texture/pull/460)
+- Add content offset bridging property to ASTableNode and ASCollectionNode. Deprecate related methods in ASTableView and ASCollectionView [Huy Nguyen](https://github.com/nguyenhuy) [#460](https://github.com/TextureGroup/Texture/pull/460)
 - Remove re-entrant access to self.view when applying initial pending state. [Adlai Holler](https://github.com/Adlai-Holler) [#510](https://github.com/TextureGroup/Texture/pull/510)
 - Small improvements in ASCollectionLayout [Huy Nguyen](https://github.com/nguyenhuy) [#509](https://github.com/TextureGroup/Texture/pull/509) [#513](https://github.com/TextureGroup/Texture/pull/513)
 - Fix retain cycle between ASImageNode and PINAnimatedImage [Phil Larson](https://github.com/plarson) [#520](https://github.com/TextureGroup/Texture/pull/520)
@@ -19,6 +19,7 @@
 - [ASDisplayNode] Ensure `-displayWillStartAsynchronously:` and `-displayDidFinish` are invoked on rasterized subnodes.  [Eric Scheers](https://github.com/smeis) [#532](https://github.com/TextureGroup/Texture/pull/532)
 - Fixed a memory corruption issue in the ASImageNode display system. [Adlai Holler](https://github.com/Adlai-Holler) [#555](https://github.com/TextureGroup/Texture/pull/555)
 - [Breaking] Rename ASCollectionGalleryLayoutSizeProviding to ASCollectionGalleryLayoutPropertiesProviding. Besides a fixed item size, it now can provide interitem and line spacings, as well as section inset [Huy Nguyen](https://github.com/nguyenhuy) [#496](https://github.com/TextureGroup/Texture/pull/496) [#533](https://github.com/TextureGroup/Texture/pull/533)
+- Deprecate `-[ASDisplayNode displayWillStart]` in favor of `-displayWillStartAsynchronously:` [Huy Nguyen](https://github.com/nguyenhuy) [536](https://github.com/TextureGroup/Texture/pull/536)
 
 ##2.4
 - Fix an issue where inserting/deleting sections could lead to inconsistent supplementary element behavior. [Adlai Holler](https://github.com/Adlai-Holler)

Source/ASDisplayNode+Subclasses.h

@@ -315,6 +315,18 @@ NS_ASSUME_NONNULL_BEGIN
  */
 - (nullable id<NSObject>)drawParametersForAsyncLayer:(_ASDisplayLayer *)layer;
 
+/**
+ * @abstract Indicates that the receiver is about to display.
+ *
+ * @discussion Deprecated in 2.5.
+ *
+ * @discussion Subclasses may override this method to be notified when display (asynchronous or synchronous) is
+ * about to begin.
+ *
+ * @note Called on the main thread only
+ */
+- (void)displayWillStart ASDISPLAYNODE_REQUIRES_SUPER ASDISPLAYNODE_DEPRECATED_MSG("Use displayWillStartAsynchronously: instead.");
+
 /**
  * @abstract Indicates that the receiver is about to display.
  *
@@ -323,7 +335,6 @@ NS_ASSUME_NONNULL_BEGIN
  *
  * @note Called on the main thread only
  */
-- (void)displayWillStart ASDISPLAYNODE_REQUIRES_SUPER;
 - (void)displayWillStartAsynchronously:(BOOL)asynchronously ASDISPLAYNODE_REQUIRES_SUPER;
 
 /**

Source/ASDisplayNode.mm

@@ -1533,7 +1533,11 @@ static void _recursivelySetDisplaySuspended(ASDisplayNode *node, CALayer *layer,
 - (void)willDisplayAsyncLayer:(_ASDisplayLayer *)layer asynchronously:(BOOL)asynchronously
 {
   // Subclass hook.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
   [self displayWillStart];
+#pragma clang diagnostic pop
+
   [self displayWillStartAsynchronously:asynchronously];
 }
 
@@ -1546,7 +1550,6 @@ static void _recursivelySetDisplaySuspended(ASDisplayNode *node, CALayer *layer,
 - (void)displayWillStart {}
 - (void)displayWillStartAsynchronously:(BOOL)asynchronously
 {
-  [self displayWillStart]; // Subclass override
   ASDisplayNodeAssertMainThread();
 
   ASDisplayNodeLogEvent(self, @"displayWillStart");

Source/ASMultiplexImageNode.mm

@@ -261,11 +261,11 @@ typedef void(^ASMultiplexImageLoadCompletionBlock)(UIImage *image, id imageIdent
   return (self.image == nil && self.animatedImage == nil && self.imageIdentifiers.count > 0);
 }
 
-/* displayWillStart in ASNetworkImageNode has a very similar implementation. Changes here are likely necessary
+/* displayWillStartAsynchronously in ASNetworkImageNode has a very similar implementation. Changes here are likely necessary
  in ASNetworkImageNode as well. */
-- (void)displayWillStart
+- (void)displayWillStartAsynchronously:(BOOL)asynchronously
 {
-  [super displayWillStart];
+  [super displayWillStartAsynchronously:asynchronously];
   
   [self didEnterPreloadState];
   

Source/ASNetworkImageNode.mm

@@ -313,7 +313,7 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   return (self.image == nil && self.animatedImage == nil && _URL != nil);
 }
 
-/* displayWillStart in ASMultiplexImageNode has a very similar implementation. Changes here are likely necessary
+/* displayWillStartAsynchronously: in ASMultiplexImageNode has a very similar implementation. Changes here are likely necessary
  in ASMultiplexImageNode as well. */
 - (void)displayWillStartAsynchronously:(BOOL)asynchronously
 {

Source/Private/ASDisplayNode+AsyncDisplay.mm

@@ -335,7 +335,7 @@
     return;
   }
   
-  ASDisplayNodeAssert(_layer, @"Expect _layer to be not nil");
+  ASDisplayNodeAssert(layer, @"Expect _layer to be not nil");
 
   // This block is called back on the main thread after rendering at the completion of the current async transaction, or immediately if !asynchronously
   asyncdisplaykit_async_transaction_operation_completion_block_t completionBlock = ^(id<NSObject> value, BOOL canceled){