From f96dfb946895c901c7823b06c26bfbbbd8b16862 Mon Sep 17 00:00:00 2001
From: Mehdi Mulani <mehdi@fb.com>
Date: Fri, 16 Feb 2018 12:08:59 -0800
Subject: [PATCH] Disable font scaling when an explicit font handler is set

Reviewed By: sahrens

Differential Revision: D7003464

fbshipit-source-id: f36ff344c50a9c63af6c852138041c1c918259c8
---
 Libraries/Text/RCTTextAttributes.m | 2 +-
 React/Views/RCTFont.h              | 1 +
 React/Views/RCTFont.mm             | 4 ++++
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/Libraries/Text/RCTTextAttributes.m b/Libraries/Text/RCTTextAttributes.m
index 26d63bdda8c..9b1ba122196 100644
--- a/Libraries/Text/RCTTextAttributes.m
+++ b/Libraries/Text/RCTTextAttributes.m
@@ -190,7 +190,7 @@ NSString *const RCTTextAttributesTagAttributeName = @"RCTTextAttributesTagAttrib
 
 - (CGFloat)effectiveFontSizeMultiplier
 {
-  return _allowFontScaling && !isnan(_fontSizeMultiplier) ? _fontSizeMultiplier : 1.0;
+  return !RCTHasFontHandlerSet() && _allowFontScaling && !isnan(_fontSizeMultiplier) ? _fontSizeMultiplier : 1.0;
 }
 
 - (UIColor *)effectiveForegroundColor
diff --git a/React/Views/RCTFont.h b/React/Views/RCTFont.h
index ba34e8f3462..711721d2a71 100644
--- a/React/Views/RCTFont.h
+++ b/React/Views/RCTFont.h
@@ -20,6 +20,7 @@ typedef UIFont *(^RCTFontHandler)(CGFloat fontSize, NSString *fontWeightDescript
  * "semibold", "extrabold", "bold", "heavy", or "black".
  */
 RCT_EXTERN void RCTSetDefaultFontHandler(RCTFontHandler handler);
+RCT_EXTERN BOOL RCTHasFontHandlerSet();
 
 @interface RCTFont : NSObject
 
diff --git a/React/Views/RCTFont.mm b/React/Views/RCTFont.mm
index 37595dd3fbf..dc3877cb352 100644
--- a/React/Views/RCTFont.mm
+++ b/React/Views/RCTFont.mm
@@ -103,6 +103,10 @@ void RCTSetDefaultFontHandler(RCTFontHandler handler) {
   defaultFontHandler = handler;
 }
 
+BOOL RCTHasFontHandlerSet() {
+  return defaultFontHandler != nil;
+}
+
 // We pass a string description of the font weight to the defaultFontHandler because UIFontWeight
 // is not defined pre-iOS 8.2.
 // Furthermore, UIFontWeight's are lossy floats, so we must use an inexact compare to figure out