[ASControlNode] hitTestDebug tool refactoring + comments:wq

AsyncDisplayKit/ASControlNode.mm

@@ -467,8 +467,7 @@ void _ASEnumerateControlEventsIncludedInMaskWithBlock(ASControlNodeEvent mask, v
     // Even if our parents don't have clipsToBounds set and would allow us to display the debug overlay, UIKit event delivery (hitTest:)
     // will not search sub-hierarchies if one of our parents does not return YES for pointInside:.  In such a scenario, hitTestSlop
     // may not be able to expand the tap target as much as desired without also setting some hitTestSlop on the limiting parents.
-    CGRect originalRect = UIEdgeInsetsInsetRect(self.bounds, [self hitTestSlop]);
+    CGRect intersectRect = UIEdgeInsetsInsetRect(self.bounds, [self hitTestSlop]);
-    CGRect intersectRect = originalRect;
     UIRectEdge clippedEdges = UIRectEdgeNone;
     UIRectEdge clipsToBoundsClippedEdges = UIRectEdgeNone;
     CALayer *layer = self.layer;
@@ -480,18 +479,33 @@ void _ASEnumerateControlEventsIncludedInMaskWithBlock(ASControlNodeEvent mask, v
     while (intersectSuperlayer && ![intersectSuperlayer.delegate respondsToSelector:@selector(contentOffset)]) {
       // Get our parent's tappable bounds.  If the parent has an associated node, consider hitTestSlop, as it will extend its pointInside:.
       CGRect parentHitRect = intersectSuperlayer.bounds;
-      BOOL parentClipsToBounds = intersectSuperlayer.masksToBounds;
+      BOOL parentClipsToBounds = NO;
+      
       ASDisplayNode *parentNode = ASLayerToDisplayNode(intersectSuperlayer);
-      if (parentNode && !parentClipsToBounds) {
+      if (parentNode) {
-        parentHitRect = UIEdgeInsetsInsetRect(parentHitRect, [parentNode hitTestSlop]);
+        UIEdgeInsets parentSlop = [parentNode hitTestSlop];
+        
+        // if parent has a hitTestSlop as well, we need to account for the fact that events will be routed towards us in that area too.
+        if (!UIEdgeInsetsEqualToEdgeInsets(UIEdgeInsetsZero, parentSlop)) {
+          parentClipsToBounds = parentNode.clipsToBounds;
+          // if the parent is clipping, this will prevent us from showing the overlay outside that area.
+          // in this case, we will make the overlay smaller so that the special highlight to indicate the overlay
+          // cannot accurately display the true tappable area is shown.
+          if (!parentClipsToBounds) {
+            parentHitRect = UIEdgeInsetsInsetRect(parentHitRect, [parentNode hitTestSlop]);
+          }
+        }
       }
       
       // Convert our current rectangle to parent coordinates, and intersect with the parent's hit rect.
       CGRect intersectRectInParentCoordinates = [intersectSuperlayer convertRect:intersectRect fromLayer:intersectLayer];
       intersectRect = CGRectIntersection(parentHitRect, intersectRectInParentCoordinates);
-      if (parentClipsToBounds) {
+      if (!CGSizeEqualToSize(parentHitRect.size, intersectRectInParentCoordinates.size)) {
-        if (!CGSizeEqualToSize(parentHitRect.size, intersectRectInParentCoordinates.size)) {
+        clippedEdges = [self setEdgesOfIntersectionForChildRect:intersectRectInParentCoordinates
-          clipsToBoundsClippedEdges = [self setEdgesOfIntersectionForChildRect:intersectRectInParentCoordinates parentRect:parentHitRect rectEdge:clipsToBoundsClippedEdges];
+                                                     parentRect:parentHitRect rectEdge:clippedEdges];
+        if (parentClipsToBounds) {
+          clipsToBoundsClippedEdges = [self setEdgesOfIntersectionForChildRect:intersectRectInParentCoordinates
+                                                                    parentRect:parentHitRect rectEdge:clipsToBoundsClippedEdges];
         }
       }
 
@@ -504,10 +518,7 @@ void _ASEnumerateControlEventsIncludedInMaskWithBlock(ASControlNodeEvent mask, v
     UIColor *fillColor = [[UIColor greenColor] colorWithAlphaComponent:0.4];
   
     // determine which edges were clipped
-    if (!CGSizeEqualToSize(originalRect.size, finalRect.size)) {
+    if (clippedEdges != UIRectEdgeNone) {
-      
-      clippedEdges = [self setEdgesOfIntersectionForChildRect:originalRect parentRect:finalRect rectEdge:clippedEdges];
-      
       const CGFloat borderWidth = 2.0;
       UIColor *superhitTestSlopClipsBorderColor = [UIColor colorWithRed:30/255.0 green:90/255.0 blue:50/255.0 alpha:0.7];
       UIColor *superClipsToBoundsBorderColor = [[UIColor orangeColor] colorWithAlphaComponent:0.8];

AsyncDisplayKit/AsyncDisplayKit+Debug.h

@@ -12,9 +12,12 @@
 @interface ASControlNode (Debugging)
 
 /**
- Class method to enable a visualization overlay of the tapable area on the ASControlNode. For app debugging purposes only.
+ Class method to enable a visualization overlay of the tappable area on the ASControlNode. For app debugging purposes only.
- Overlay = translucent green color, edges clipped by hitTestDebug of any parent in the hierarchy = dark green bordered edge,
+ NOTE: GESTURE RECOGNIZERS, (including tap gesture recognizers on a control node) WILL NOT BE VISUALIZED!!!
- edges clipped by clipToBounds = YES of any parent in the hierarchy = orange bordered edge.
+ Overlay = translucent GREEN color, 
+ edges that are clipped by the tappable area of any parent (their bounds + hitTestSlop) in the hierarchy = DARK GREEN BORDERED EDGE,
+ edges that are clipped by clipToBounds = YES of any parent in the hierarchy = ORANGE BORDERED EDGE (may still receive touches beyond
+ overlay rect, but can't be visualized).
  @param enable Specify YES to make this debug feature enabled when messaging the ASControlNode class.
  */
 + (void)setEnableHitTestDebug:(BOOL)enable;