[Yoga] Implement ASYogaLayoutSpec, a simplified integration strategy …

…for Yoga. (#270)

* [Yoga] Implement ASYogaLayoutSpec, an experimental alternative to full-tree integration.

This approach allows us to avoid any ASDisplayNode.mm integration points.
However, it is not yet proven to be possible to achieve correctness with this approach.

The entry point (to start calculating), and the measurement function inputs, lack
the full expressiveness of ASSizeRange; we need to make sure that workarounds like
using style.minSize are successful in simulating the behavior of a full Yoga tree.

* [Yoga] Fix file comments, move towards <ASLayoutElement> support.

* [Yoga] Important fix for simplified, non-contiguous Yoga integration.

* [Yoga] Complete implementation of manual memory management (__bridge_transfer, YGNodeFree)

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -180,6 +180,10 @@
 		8BBBAB8D1CEBAF1E00107FC6 /* ASDefaultPlaybackButton.m in Sources */ = {isa = PBXBuildFile; fileRef = 8B0768B21CE752EC002E1453 /* ASDefaultPlaybackButton.m */; };
 		8BDA5FC71CDBDF91007D13B2 /* ASVideoPlayerNode.h in Headers */ = {isa = PBXBuildFile; fileRef = 8BDA5FC31CDBDDE1007D13B2 /* ASVideoPlayerNode.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		8BDA5FC81CDBDF95007D13B2 /* ASVideoPlayerNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = 8BDA5FC41CDBDDE1007D13B2 /* ASVideoPlayerNode.mm */; };
+		9019FBBD1ED8061D00C45F72 /* ASYogaLayoutSpec.h in Headers */ = {isa = PBXBuildFile; fileRef = 9019FBB91ED8061D00C45F72 /* ASYogaLayoutSpec.h */; };
+		9019FBBE1ED8061D00C45F72 /* ASYogaLayoutSpec.mm in Sources */ = {isa = PBXBuildFile; fileRef = 9019FBBA1ED8061D00C45F72 /* ASYogaLayoutSpec.mm */; };
+		9019FBBF1ED8061D00C45F72 /* ASYogaUtilities.h in Headers */ = {isa = PBXBuildFile; fileRef = 9019FBBB1ED8061D00C45F72 /* ASYogaUtilities.h */; };
+		9019FBC01ED8061D00C45F72 /* ASYogaUtilities.mm in Sources */ = {isa = PBXBuildFile; fileRef = 9019FBBC1ED8061D00C45F72 /* ASYogaUtilities.mm */; };
 		90FC784F1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm in Sources */ = {isa = PBXBuildFile; fileRef = 90FC784E1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm */; };
 		92DD2FE61BF4D05E0074C9DD /* MapKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 92DD2FE51BF4D05E0074C9DD /* MapKit.framework */; settings = {ATTRIBUTES = (Weak, ); }; };
 		92DD2FE71BF4D0850074C9DD /* ASMapNode.mm in Sources */ = {isa = PBXBuildFile; fileRef = 92DD2FE21BF4B97E0074C9DD /* ASMapNode.mm */; };
@@ -676,6 +680,10 @@
 		8B0768B21CE752EC002E1453 /* ASDefaultPlaybackButton.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASDefaultPlaybackButton.m; sourceTree = "<group>"; };
 		8BDA5FC31CDBDDE1007D13B2 /* ASVideoPlayerNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASVideoPlayerNode.h; sourceTree = "<group>"; };
 		8BDA5FC41CDBDDE1007D13B2 /* ASVideoPlayerNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASVideoPlayerNode.mm; sourceTree = "<group>"; };
+		9019FBB91ED8061D00C45F72 /* ASYogaLayoutSpec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASYogaLayoutSpec.h; sourceTree = "<group>"; };
+		9019FBBA1ED8061D00C45F72 /* ASYogaLayoutSpec.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASYogaLayoutSpec.mm; sourceTree = "<group>"; };
+		9019FBBB1ED8061D00C45F72 /* ASYogaUtilities.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASYogaUtilities.h; sourceTree = "<group>"; };
+		9019FBBC1ED8061D00C45F72 /* ASYogaUtilities.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASYogaUtilities.mm; sourceTree = "<group>"; };
 		90FC784E1E4BFE1B00383C5A /* ASDisplayNode+Yoga.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = "ASDisplayNode+Yoga.mm"; sourceTree = "<group>"; };
 		92DD2FE11BF4B97E0074C9DD /* ASMapNode.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ASMapNode.h; sourceTree = "<group>"; };
 		92DD2FE21BF4B97E0074C9DD /* ASMapNode.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ASMapNode.mm; sourceTree = "<group>"; };
@@ -1481,6 +1489,10 @@
 				9C49C36E1B853957000B0DD5 /* ASStackLayoutElement.h */,
 				ACF6ED161B17843500DA7C62 /* ASStackLayoutSpec.h */,
 				ACF6ED171B17843500DA7C62 /* ASStackLayoutSpec.mm */,
+				9019FBB91ED8061D00C45F72 /* ASYogaLayoutSpec.h */,
+				9019FBBA1ED8061D00C45F72 /* ASYogaLayoutSpec.mm */,
+				9019FBBB1ED8061D00C45F72 /* ASYogaUtilities.h */,
+				9019FBBC1ED8061D00C45F72 /* ASYogaUtilities.mm */,
 			);
 			path = Layout;
 			sourceTree = "<group>";
@@ -1643,6 +1655,7 @@
 				B35062571B010F070018CF92 /* ASAssert.h in Headers */,
 				CCBBBF5D1EB161760069AA91 /* ASRangeManagingNode.h in Headers */,
 				B35062581B010F070018CF92 /* ASAvailability.h in Headers */,
+				9019FBBF1ED8061D00C45F72 /* ASYogaUtilities.h in Headers */,
 				DE84918D1C8FFF2B003D89E9 /* ASRunLoopQueue.h in Headers */,
 				CC0F88621E4281E200576FED /* ASSectionController.h in Headers */,
 				A2763D7A1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */,
@@ -1751,6 +1764,7 @@
 				CCF18FF41D2575E300DF5895 /* NSIndexSet+ASHelpers.h in Headers */,
 				83A7D95C1D44548100BF333E /* ASWeakMap.h in Headers */,
 				E5711A2C1C840C81009619D4 /* ASCollectionElement.h in Headers */,
+				9019FBBD1ED8061D00C45F72 /* ASYogaLayoutSpec.h in Headers */,
 				6947B0BE1E36B4E30007C478 /* ASStackUnpositionedLayout.h in Headers */,
 				CC4C2A771D88E3BF0039ACAB /* ASTraceEvent.h in Headers */,
 				254C6B7B1BF94DF4003EC431 /* ASTextKitRenderer+Positioning.h in Headers */,
@@ -2086,6 +2100,7 @@
 				AC026B721BD57DBF00BBC17E /* _ASHierarchyChangeSet.mm in Sources */,
 				B35062421B010EFD0018CF92 /* _ASAsyncTransactionGroup.m in Sources */,
 				CCA282BD1E9EABDD0037E8B7 /* ASTipProvider.m in Sources */,
+				9019FBC01ED8061D00C45F72 /* ASYogaUtilities.mm in Sources */,
 				B350624A1B010EFD0018CF92 /* _ASCoreAnimationExtras.mm in Sources */,
 				68EE0DC01C1B4ED300BA1B99 /* ASMainSerialQueue.mm in Sources */,
 				B35062101B010EFD0018CF92 /* _ASDisplayLayer.mm in Sources */,
@@ -2167,6 +2182,7 @@
 				6907C25A1DC4ECFE00374C66 /* ASObjectDescriptionHelpers.m in Sources */,
 				B35062051B010EFD0018CF92 /* ASMultiplexImageNode.mm in Sources */,
 				B35062251B010EFD0018CF92 /* ASMutableAttributedStringBuilder.m in Sources */,
+				9019FBBE1ED8061D00C45F72 /* ASYogaLayoutSpec.mm in Sources */,
 				B35062071B010EFD0018CF92 /* ASNetworkImageNode.mm in Sources */,
 				34EFC76D1B701CF100AD841F /* ASOverlayLayoutSpec.mm in Sources */,
 				044285101BAA64EC00D16268 /* ASTwoDimensionalArrayUtils.m in Sources */,

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## master
 
 * Add your own contributions to the next release on the line below this with your name.
+- [Yoga] Implement ASYogaLayoutSpec, a simplified integration strategy for Yoga-powered layout calculation. [Scott Goodson](https://github.com/appleguy)
 - Fixed an issue where calls to setNeedsDisplay and setNeedsLayout would stop working on loaded nodes. [Garrett Moon](https://github.com/garrettmoon)
 - [ASTextKitFontSizeAdjuster] [Ricky Cancro] Replace use of NSAttributedString's boundingRectWithSize:options:context: with NSLayoutManager's boundingRectForGlyphRange:inTextContainer:
 - Add support for IGListKit post-removal-of-IGListSectionType, in preparation for IGListKit 3.0.0 release. [Adlai Holler](https://github.com/Adlai-Holler) [#49](https://github.com/TextureGroup/Texture/pull/49)

Source/ASDisplayNode+Beta.h

@@ -171,15 +171,18 @@ extern void ASDisplayNodePerformBlockOnEveryYogaChild(ASDisplayNode * _Nullable
 @interface ASDisplayNode (Yoga)
 
 @property (nonatomic, strong, nullable) NSArray *yogaChildren;
-@property (nonatomic, strong, nullable) ASLayout *yogaCalculatedLayout;
 
 - (void)addYogaChild:(ASDisplayNode *)child;
 - (void)removeYogaChild:(ASDisplayNode *)child;
 
+- (void)semanticContentAttributeDidChange:(UISemanticContentAttribute)attribute;
+
+#if YOGA_TREE_CONTIGUOUS
+@property (nonatomic, strong, nullable) ASLayout *yogaCalculatedLayout;
 // These methods should not normally be called directly.
 - (void)invalidateCalculatedYogaLayout;
 - (void)calculateLayoutFromYogaRoot:(ASSizeRange)rootConstrainedSize;
-- (void)semanticContentAttributeDidChange:(UISemanticContentAttribute)attribute;
+#endif
 
 @end