From e737535f18cb837e0ffda4e7a703227a3f89a418 Mon Sep 17 00:00:00 2001
From: Valentin Shergin <shergin@fb.com>
Date: Thu, 13 Feb 2020 11:37:55 -0800
Subject: [PATCH] Fabric: Small optimization in
 RCTNSAttributedStringFromAttributedString

Summary:
With new logic we save one attributed string copy operation.

Changelog: [Internal] Fabric-specific internal change.

Reviewed By: sammy-SC

Differential Revision: D19844371

fbshipit-source-id: 62f6b0f9c8514a1b55224ccaa52c8fa89c06c9e7
---
 .../platform/ios/RCTAttributedTextUtils.mm    | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTAttributedTextUtils.mm b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTAttributedTextUtils.mm
index 17149b70ad2..4bc9870a628 100644
--- a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTAttributedTextUtils.mm
+++ b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTAttributedTextUtils.mm
@@ -228,7 +228,7 @@ NSAttributedString *RCTNSAttributedStringFromAttributedString(const AttributedSt
   [nsAttributedString beginEditing];
 
   for (auto fragment : attributedString.getFragments()) {
-    NSAttributedString *nsAttributedStringFragment;
+    NSMutableAttributedString *nsAttributedStringFragment;
 
     if (fragment.isAttachment()) {
       auto layoutMetrics = fragment.parentShadowView.layoutMetrics;
@@ -239,18 +239,15 @@ NSAttributedString *RCTNSAttributedStringFromAttributedString(const AttributedSt
       attachment.image = placeholderImage;
       attachment.bounds = bounds;
 
-      nsAttributedStringFragment = [NSAttributedString attributedStringWithAttachment:attachment];
+      nsAttributedStringFragment = [[NSMutableAttributedString attributedStringWithAttachment:attachment] mutableCopy];
     } else {
       NSString *string = [NSString stringWithCString:fragment.string.c_str() encoding:NSUTF8StringEncoding];
 
-      nsAttributedStringFragment =
-          [[NSAttributedString alloc] initWithString:string
-                                          attributes:RCTNSTextAttributesFromTextAttributes(fragment.textAttributes)];
+      nsAttributedStringFragment = [[NSMutableAttributedString alloc]
+          initWithString:string
+              attributes:RCTNSTextAttributesFromTextAttributes(fragment.textAttributes)];
     }
 
-    NSMutableAttributedString *nsMutableAttributedStringFragment =
-        [[NSMutableAttributedString alloc] initWithAttributedString:nsAttributedStringFragment];
-
     if (fragment.parentShadowView.componentHandle) {
       RCTWeakEventEmitterWrapper *eventEmitterWrapper = [RCTWeakEventEmitterWrapper new];
       eventEmitterWrapper.eventEmitter = fragment.parentShadowView.eventEmitter;
@@ -258,11 +255,11 @@ NSAttributedString *RCTNSAttributedStringFromAttributedString(const AttributedSt
       NSDictionary<NSAttributedStringKey, id> *additionalTextAttributes =
           @{RCTAttributedStringEventEmitterKey : eventEmitterWrapper};
 
-      [nsMutableAttributedStringFragment addAttributes:additionalTextAttributes
-                                                 range:NSMakeRange(0, nsMutableAttributedStringFragment.length)];
+      [nsAttributedStringFragment addAttributes:additionalTextAttributes
+                                          range:NSMakeRange(0, nsAttributedStringFragment.length)];
     }
 
-    [nsAttributedString appendAttributedString:nsMutableAttributedStringFragment];
+    [nsAttributedString appendAttributedString:nsAttributedStringFragment];
   }
 
   [nsAttributedString endEditing];