Add a failing unit test for the automatic subnode management range issue (#2826)

Author: Adlai Holler

AsyncDisplayKit/ASCellNode.h

@@ -12,7 +12,7 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-@class ASCellNode;
+@class ASCellNode, ASTextNode;
 
 typedef NSUInteger ASCellNodeAnimation;
 
@@ -205,6 +205,11 @@ typedef NS_ENUM(NSUInteger, ASCellNodeVisibilityEvent) {
  */
 @property (nonatomic, assign) UIEdgeInsets textInsets;
 
+/**
+ * The text node used by this cell node.
+ */
+@property (nonatomic, strong, readonly) ASTextNode *textNode;
+
 @end
 
 NS_ASSUME_NONNULL_END

AsyncDisplayKit/ASCellNode.mm

@@ -395,13 +395,6 @@ - (void)handleVisibilityChange:(BOOL)isVisible
 #pragma mark -
 #pragma mark ASTextCellNode
 
-@interface ASTextCellNode ()
-
-@property (nonatomic, strong) ASTextNode *textNode;
-
-@end
-
-
 @implementation ASTextCellNode
 
 static const CGFloat kASTextCellNodeDefaultFontSize = 18.0f;
@@ -420,7 +413,7 @@ - (instancetype)initWithAttributes:(NSDictionary *)textAttributes insets:(UIEdge
     _textInsets = textInsets;
     _textAttributes = [textAttributes copy];
     _textNode = [[ASTextNode alloc] init];
-    [self addSubnode:_textNode];
+    self.automaticallyManagesSubnodes = YES;
   }
   return self;
 }

AsyncDisplayKitTests/ASCollectionViewTests.mm

@@ -1024,4 +1024,32 @@ - (void)testInitialRangeBounds
   XCTAssertEqual([[cn valueForKeyPath:@"rangeController.currentRangeMode"] integerValue], ASLayoutRangeModeMinimum, @"Expected range mode to be minimum before scrolling begins.");
 }
 
+/**
+ * This tests an issue where, since subnode insertions aren't applied until the UIKit layout pass,
+ * which we trigger during the display phase, subnodes like network image nodes are not preloading
+ * until this layout pass happens which is too late.
+ */
+- (void)DISABLED_testThatAutomaticallyManagedSubnodesGetPreloadCallBeforeDisplay
+{
+  UIWindow *window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
+  ASCollectionViewTestController *testController = [[ASCollectionViewTestController alloc] initWithNibName:nil bundle:nil];
+  window.rootViewController = testController;
+  ASCollectionNode *cn = testController.collectionNode;
+
+  __block NSInteger itemCount = 100;
+  testController.asyncDelegate->_itemCounts = {itemCount};
+  [window makeKeyAndVisible];
+  [window layoutIfNeeded];
+
+  [cn waitUntilAllUpdatesAreCommitted];
+  for (NSInteger i = 0; i < itemCount; i++) {
+    ASTextCellNodeWithSetSelectedCounter *node = [cn nodeForItemAtIndexPath:[NSIndexPath indexPathForItem:i inSection:0]];
+    XCTAssert(node.automaticallyManagesSubnodes, @"Expected test cell node to use automatic subnode management. Can modify the test with a different class if needed.");
+    ASDisplayNode *subnode = node.textNode;
+    XCTAssertEqualObjects(NSStringFromASInterfaceState(subnode.interfaceState), NSStringFromASInterfaceState(node.interfaceState), @"Subtree interface state should match cell node interface state for ASM nodes.");
+    XCTAssert(node.inDisplayState || !node.nodeLoaded, @"Only nodes in the display range should be loaded.");
+  }
+
+}
+
 @end