Add some nullability specifiers to our public headers (#2291)

AsyncDisplayKit/ASButtonNode.h

@@ -11,6 +11,8 @@
 #import <AsyncDisplayKit/ASTextNode.h>
 #import <AsyncDisplayKit/ASImageNode.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 /**
  Image alignment defines where the image will be placed relative to the text.
  */
@@ -23,9 +25,9 @@ typedef NS_ENUM(NSInteger, ASButtonNodeImageAlignment) {
 
 @interface ASButtonNode : ASControlNode
 
-@property (nonatomic, readonly) ASTextNode  * _Nonnull titleNode;
+@property (nonatomic, readonly) ASTextNode  * titleNode;
-@property (nonatomic, readonly) ASImageNode * _Nonnull imageNode;
+@property (nonatomic, readonly) ASImageNode * imageNode;
-@property (nonatomic, readonly) ASImageNode * _Nonnull backgroundImageNode;
+@property (nonatomic, readonly) ASImageNode * backgroundImageNode;
 
 /**
  Spacing between image and title. Defaults to 8.0.
@@ -85,7 +87,7 @@ typedef NS_ENUM(NSInteger, ASButtonNodeImageAlignment) {
  *  @param color The color to use for the title.
  *  @param state The state that uses the specified title. The possible values are described in ASControlState.
  */
-- (void)setTitle:(nonnull NSString *)title withFont:(nullable UIFont *)font withColor:(nullable UIColor *)color forState:(ASControlState)state;
+- (void)setTitle:(NSString *)title withFont:(nullable UIFont *)font withColor:(nullable UIColor *)color forState:(ASControlState)state;
 #endif
 /**
  *  Returns the image used for a button state.
@@ -94,7 +96,7 @@ typedef NS_ENUM(NSInteger, ASButtonNodeImageAlignment) {
  *
  *  @return The image used for the specified state.
  */
-- (UIImage * _Nullable)imageForState:(ASControlState)state;
+- (nullable UIImage *)imageForState:(ASControlState)state;
 
 /**
  *  Sets the image to use for the specified state.
@@ -120,6 +122,8 @@ typedef NS_ENUM(NSInteger, ASButtonNodeImageAlignment) {
  *
  *  @return The background image used for the specified state.
  */
-- (UIImage * _Nullable)backgroundImageForState:(ASControlState)state;
+- (nullable UIImage *)backgroundImageForState:(ASControlState)state;
 
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASDisplayNode.h

@@ -18,6 +18,8 @@
 #import <AsyncDisplayKit/ASLayoutable.h>
 #import <AsyncDisplayKit/ASContextTransitioning.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 #define ASDisplayNodeLoggingEnabled 0
 
 @class ASDisplayNode;
@@ -40,12 +42,12 @@ typedef CALayer * _Nonnull(^ASDisplayNodeLayerBlock)();
 /**
  * ASDisplayNode loaded callback block. This block is called BEFORE the -didLoad method and is always called on the main thread.
  */
-typedef void (^ASDisplayNodeDidLoadBlock)(__kindof ASDisplayNode * _Nonnull node);
+typedef void (^ASDisplayNodeDidLoadBlock)(__kindof ASDisplayNode * node);
 
 /**
  * ASDisplayNode will / did render node content in context.
  */
-typedef void (^ASDisplayNodeContextModifier)(_Nonnull CGContextRef context);
+typedef void (^ASDisplayNodeContextModifier)(CGContextRef context);
 
 /**
  * ASDisplayNode layout spec block. This block can be used instead of implementing layoutSpecThatFits: in subclass
@@ -102,7 +104,6 @@ extern NSInteger const ASDefaultDrawingPriority;
  *
  */
 
-NS_ASSUME_NONNULL_BEGIN
 @interface ASDisplayNode : ASDealloc2MainObject <ASLayoutable>
 
 

AsyncDisplayKit/ASImageNode.h

@@ -11,6 +11,7 @@
 #import <AsyncDisplayKit/ASControlNode.h>
 
 #import "ASImageProtocols.h"
+#import "ASBaseDefines.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
@@ -120,7 +121,7 @@ typedef UIImage * _Nullable (^asimagenode_modification_block_t)(UIImage *image);
  * `displaySuspended` is YES, `displayCompletionBlock` is will be
  * performed immediately and `YES` will be passed for `canceled`.
  */
-- (void)setNeedsDisplayWithCompletion:(void (^ _Nullable)(BOOL canceled))displayCompletionBlock;
+- (void)setNeedsDisplayWithCompletion:(nullable void (^)(BOOL canceled))displayCompletionBlock;
 
 #if TARGET_OS_TV
 /** 
@@ -164,9 +165,9 @@ typedef UIImage * _Nullable (^asimagenode_modification_block_t)(UIImage *image);
 
 @interface ASImageNode (Unavailable)
 
-- (instancetype)initWithLayerBlock:(ASDisplayNodeLayerBlock)viewBlock didLoadBlock:(nullable ASDisplayNodeDidLoadBlock)didLoadBlock __unavailable;
+- (instancetype)initWithLayerBlock:(ASDisplayNodeLayerBlock)viewBlock didLoadBlock:(nullable ASDisplayNodeDidLoadBlock)didLoadBlock AS_UNAVAILABLE();
 
-- (instancetype)initWithViewBlock:(ASDisplayNodeViewBlock)viewBlock didLoadBlock:(nullable ASDisplayNodeDidLoadBlock)didLoadBlock __unavailable;
+- (instancetype)initWithViewBlock:(ASDisplayNodeViewBlock)viewBlock didLoadBlock:(nullable ASDisplayNodeDidLoadBlock)didLoadBlock AS_UNAVAILABLE();
 
 @end
 

AsyncDisplayKit/ASNavigationController.h

@@ -14,6 +14,10 @@
 
 #import "ASVisibilityProtocols.h"
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface ASNavigationController : UINavigationController <ASManagesChildVisibilityDepth>
 
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASPagerFlowLayout.h

@@ -12,6 +12,10 @@
 
 #import <UIKit/UIKit.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface ASPagerFlowLayout : UICollectionViewFlowLayout
 
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASTabBarController.h

@@ -14,6 +14,10 @@
 
 #import "ASVisibilityProtocols.h"
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface ASTabBarController : UITabBarController <ASManagesChildVisibilityDepth>
 
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASTableNode.h

@@ -14,6 +14,8 @@
 #import <AsyncDisplayKit/ASDisplayNode.h>
 #import <AsyncDisplayKit/ASRangeControllerUpdateRangeProtocol+Beta.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 @protocol ASTableDataSource;
 @protocol ASTableDelegate;
 @class ASTableView;
@@ -34,3 +36,5 @@
 @property (weak, nonatomic) id <ASTableDataSource> dataSource;
 
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASTextNode+Beta.h

@@ -18,7 +18,7 @@ NS_ASSUME_NONNULL_BEGIN
  @abstract An array of descending scale factors that will be applied to this text node to try to make it fit within its constrained size
  @default nil (no scaling)
  */
-@property (nullable, nonatomic, copy) NSArray *pointSizeScaleFactors;
+@property (nullable, nonatomic, copy) NSArray<NSNumber *> *pointSizeScaleFactors;
 
 /**
  @abstract Text margins for text laid out in the text node.

AsyncDisplayKit/ASVisibilityProtocols.h

@@ -14,6 +14,8 @@
 
 #import "ASBaseDefines.h"
 
+NS_ASSUME_NONNULL_BEGIN
+
 @class UIViewController;
 
 ASDISPLAYNODE_EXTERN_C_BEGIN
@@ -106,3 +108,5 @@ ASDISPLAYNODE_EXTERN_C_END
   _parentManagesVisibilityDepth = NO; \
   [self visibilityDepthDidChange]; \
 }
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/AsyncDisplayKit+Debug.h

@@ -14,6 +14,8 @@
 #import "ASImageNode.h"
 #import "ASRangeController.h"
 
+NS_ASSUME_NONNULL_BEGIN
+
 @interface ASImageNode (Debugging)
 
 /**
@@ -67,3 +69,4 @@
 
 @end
 
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/Details/ASCollectionInternal.h

@@ -12,15 +12,19 @@
 
 #import <AsyncDisplayKit/ASCollectionView.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 @protocol ASCollectionViewLayoutFacilitatorProtocol;
 @class ASCollectionNode;
 @class ASDataController;
 @class ASRangeController;
 
 @interface ASCollectionView ()
-- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator ownedByNode:(BOOL)ownedByNode;
+- (instancetype)_initWithFrame:(CGRect)frame collectionViewLayout:(UICollectionViewLayout *)layout layoutFacilitator:(nullable id<ASCollectionViewLayoutFacilitatorProtocol>)layoutFacilitator ownedByNode:(BOOL)ownedByNode;
 
 @property (nonatomic, weak, readwrite) ASCollectionNode *collectionNode;
 @property (nonatomic, strong, readonly) ASDataController *dataController;
 @property (nonatomic, strong, readonly) ASRangeController *rangeController;
 @end
+
+NS_ASSUME_NONNULL_END

AsyncDisplayKit/UIImage+ASConvenience.h

@@ -13,9 +13,11 @@
 #import <UIKit/UIImage.h>
 #import <UIKit/UIBezierPath.h>
 
+NS_ASSUME_NONNULL_BEGIN
+
 // High-performance flat-colored, rounded-corner resizable images
 //
-// For "Baked-in Opaque" corners, set cornerColor equal to the color behind the rounded image object, e.g. the background color.
+// For "Baked-in Opaque" corners, set cornerColor equal to the color behind the rounded image object, i.e. the background color.
 // For "Baked-in Alpha" corners, set cornerColor = [UIColor clearColor]
 //
 // See http://asyncdisplaykit.org/docs/corner-rounding.html for an explanation.
@@ -45,7 +47,7 @@
 + (UIImage *)as_resizableRoundedImageWithCornerRadius:(CGFloat)cornerRadius
                                           cornerColor:(UIColor *)cornerColor
                                             fillColor:(UIColor *)fillColor
-                                          borderColor:(UIColor *)borderColor
+                                          borderColor:(nullable UIColor *)borderColor
                                           borderWidth:(CGFloat)borderWidth;
 
 /**
@@ -62,10 +64,11 @@
 + (UIImage *)as_resizableRoundedImageWithCornerRadius:(CGFloat)cornerRadius
                                           cornerColor:(UIColor *)cornerColor
                                             fillColor:(UIColor *)fillColor
-                                          borderColor:(UIColor *)borderColor
+                                          borderColor:(nullable UIColor *)borderColor
                                           borderWidth:(CGFloat)borderWidth
                                        roundedCorners:(UIRectCorner)roundedCorners
                                                 scale:(CGFloat)scale;
 
 @end
 
+NS_ASSUME_NONNULL_END