From 9d866f63e3e5ae9e601582a5a86670abffbc6dc4 Mon Sep 17 00:00:00 2001
From: Ben Cunningham <bcunning@fb.com>
Date: Mon, 27 Oct 2014 16:46:01 -0700
Subject: [PATCH] Fix text highlighting in UIScrollView
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Highlight target layers with non-zero bounds.origin exhibited broken
text highlighting behavior. Highlights would appear offset by the
layer’s bounds.origin, and would not align with their target text. This
most often appeared in UIScrollView, where highlights would appear
incorrectly offset once the scroll view was scrolled. Fix by accounting
for bounds.origin in the calculations of the text overlay highlight
rects.
---
 AsyncDisplayKit/ASTextNode.mm | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/AsyncDisplayKit/ASTextNode.mm b/AsyncDisplayKit/ASTextNode.mm
index 4cbc684208..cc92af2b7c 100644
--- a/AsyncDisplayKit/ASTextNode.mm
+++ b/AsyncDisplayKit/ASTextNode.mm
@@ -554,6 +554,12 @@ ASDISPLAYNODE_INLINE CGFloat ceilPixelValue(CGFloat f)
         for (NSValue *rectValue in highlightRects) {
           CGRect rendererRect = [[self class] _adjustRendererRect:rectValue.CGRectValue forShadowPadding:_shadower.shadowPadding];
           CGRect highlightedRect = [self.layer convertRect:rendererRect toLayer:highlightTargetLayer];
+
+          // We set our overlay layer's frame to the bounds of the highlight target layer.
+          // Offset highlight rects to avoid double-counting target layer's bounds.origin.
+          highlightedRect.origin.x -= highlightTargetLayer.bounds.origin.x;
+          highlightedRect.origin.y -= highlightTargetLayer.bounds.origin.y;
+          
           [converted addObject:[NSValue valueWithCGRect:highlightedRect]];
         }