From 61774088d79ac3ab730fa55d175d681b10ae50f3 Mon Sep 17 00:00:00 2001
From: Jakub Piasecki <jakubpiasecki67@gmail.com>
Date: Wed, 7 Feb 2024 07:25:30 -0800
Subject: [PATCH] Make font styling work when using specific font name on the
 new architecture (#37109)

Summary:
Currently, when `fontFamily` style is set to a specific font instead of a font family, [that specific font is used](https://github.com/facebook/react-native/blob/2058da8f2012578c3e82f1af19c3248346655f9a/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTFontUtils.mm#L126) to display the text on iOS when using the new architecture. This is different behavior to the old architecture, where the font family and [font properties were extracted from the specified](https://github.com/facebook/react-native/blob/2058da8f2012578c3e82f1af19c3248346655f9a/packages/react-native/React/Views/RCTFont.mm#L450-L457) font and overridden if not provided by the user.

## Changelog:

[IOS] [FIXED] - Make font resolution work when using specific font name on the new architecture

Pull Request resolved: https://github.com/facebook/react-native/pull/37109

Test Plan:
You can verify the problem on a simple snippet:
```jsx
import React from 'react';
import {SafeAreaView, Text} from 'react-native';

function App() {
  return (
    <SafeAreaView style={{flex: 1}}>
      <Text
        style={{
          fontFamily: 'Helvetica Light Oblique',
          fontWeight: 'bold',
          fontStyle: 'normal',
        }}>
        Some random text
      </Text>
    </SafeAreaView>
  );
}

export default App;
```

<details>
<summary>
Here's before & after
</summary>

Without changes from this PR:
<img src="https://user-images.githubusercontent.com/21055725/234618852-07cbe67c-f534-4b04-b760-828f4edef549.png" width=400 />

With changes from this PR:
<img src="https://user-images.githubusercontent.com/21055725/234618902-9e44a389-8f27-4ab0-95dc-e34ca781d2ed.png" width=400 />

</details>

Reviewed By: NickGerleman

Differential Revision: D45351185

Pulled By: sammy-SC

fbshipit-source-id: 1f0a6a52a714ca4989775817d1fb53ae593143f8
---
 .../textlayoutmanager/RCTFontUtils.mm         | 21 +++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTFontUtils.mm b/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTFontUtils.mm
index 4f8d5aa0703293..dd5900b41ce399 100644
--- a/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTFontUtils.mm
+++ b/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTFontUtils.mm
@@ -35,9 +35,6 @@ static RCTFontProperties RCTResolveFontProperties(
 {
   fontProperties.family = fontProperties.family.length ? fontProperties.family : baseFontProperties.family;
   fontProperties.size = !isnan(fontProperties.size) ? fontProperties.size : baseFontProperties.size;
-  fontProperties.weight = !isnan(fontProperties.weight) ? fontProperties.weight : baseFontProperties.weight;
-  fontProperties.style =
-      fontProperties.style != RCTFontStyleUndefined ? fontProperties.style : baseFontProperties.style;
   fontProperties.variant =
       fontProperties.variant != RCTFontVariantUndefined ? fontProperties.variant : baseFontProperties.variant;
   return fontProperties;
@@ -116,9 +113,15 @@ static RCTFontStyle RCTGetFontStyle(UIFont *font)
   if ([fontProperties.family isEqualToString:defaultFontProperties.family]) {
     // Handle system font as special case. This ensures that we preserve
     // the specific metrics of the standard system font as closely as possible.
+    fontProperties.weight = !isnan(fontProperties.weight) ? fontProperties.weight : defaultFontProperties.weight;
+    fontProperties.style =
+        fontProperties.style != RCTFontStyleUndefined ? fontProperties.style : defaultFontProperties.style;
+
     font = RCTDefaultFontWithFontProperties(fontProperties);
   } else {
     NSArray<NSString *> *fontNames = [UIFont fontNamesForFamilyName:fontProperties.family];
+    UIFontWeight fontWeight = fontProperties.weight;
+    RCTFontStyle fontStyle = fontProperties.style;
 
     if (fontNames.count == 0) {
       // Gracefully handle being given a font name rather than font family, for
@@ -129,18 +132,24 @@ static RCTFontStyle RCTGetFontStyle(UIFont *font)
         // Failback to system font.
         font = [UIFont systemFontOfSize:effectiveFontSize weight:fontProperties.weight];
       }
-    } else {
+
+      fontNames = [UIFont fontNamesForFamilyName:font.familyName];
+      fontWeight = isnan(fontWeight) ? RCTGetFontWeight(font) : fontWeight;
+      fontStyle = fontStyle == RCTFontStyleUndefined ? RCTGetFontStyle(font) : fontStyle;
+    }
+
+    if (fontNames.count != 0) {
       // Get the closest font that matches the given weight for the fontFamily
       CGFloat closestWeight = INFINITY;
       for (NSString *name in fontNames) {
         UIFont *fontMatch = [UIFont fontWithName:name size:effectiveFontSize];
 
-        if (RCTGetFontStyle(fontMatch) != fontProperties.style) {
+        if (RCTGetFontStyle(fontMatch) != fontStyle) {
           continue;
         }
 
         CGFloat testWeight = RCTGetFontWeight(fontMatch);
-        if (ABS(testWeight - fontProperties.weight) < ABS(closestWeight - fontProperties.weight)) {
+        if (ABS(testWeight - fontWeight) < ABS(closestWeight - fontWeight)) {
           font = fontMatch;
           closestWeight = testWeight;
         }