From 00fef63b4bd16d7c89555d40302a796df4fe92e5 Mon Sep 17 00:00:00 2001
From: Yevhenii <evgeny.kotyrlo@gmail.com>
Date: Mon, 12 Oct 2026 08:04:40 +0300
Subject: [PATCH] Align text to the left by default in LTR on iOS

A paragraph that declares no textAlign gets an explicit alignment on iOS
only when its layout direction is right to left (#57634). In a left-to-right
layout the paragraph style keeps NSTextAlignmentNatural, which UIKit resolves
against the app's localization rather than the paragraph, so in an app
running in a right-to-left language a left-to-right subtree is drawn flush
right while Android draws it flush left.

Resolve the alignment whenever the paragraph's layout direction is known,
which is what RCTIsParagraphStyleEffectivelySame already assumes when it
compares paragraph styles.
---
 .../Tests/Text/RCTAttributedTextUtilsTest.mm  | 25 +++++++++++++++++++
 .../RCTAttributedTextUtils.mm                 |  2 +-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/packages/react-native/React/Tests/Text/RCTAttributedTextUtilsTest.mm b/packages/react-native/React/Tests/Text/RCTAttributedTextUtilsTest.mm
index a02622d5d7d7..242e40e644ae 100644
--- a/packages/react-native/React/Tests/Text/RCTAttributedTextUtilsTest.mm
+++ b/packages/react-native/React/Tests/Text/RCTAttributedTextUtilsTest.mm
@@ -43,6 +43,15 @@ static NSTextAlignment NSTextAlignmentFromTextAlign(NSString *textAlign, LayoutD
   return paragraphStyle.alignment;
 }
 
+static NSParagraphStyle *ParagraphStyleFromLayoutDirection(std::optional<LayoutDirection> layoutDirection)
+{
+  TextAttributes textAttributes;
+  textAttributes.layoutDirection = layoutDirection;
+
+  NSDictionary<NSAttributedStringKey, id> *attributes = RCTNSTextAttributesFromTextAttributes(textAttributes);
+  return attributes[NSParagraphStyleAttributeName];
+}
+
 static UIFont *FontFromSettings(std::optional<std::string> settings, std::optional<FontWeight> weight = std::nullopt)
 {
   TextAttributes textAttributes;
@@ -133,6 +142,22 @@ - (void)testTextAlignmentStartAndEndResolveWithLayoutDirection
   XCTAssertEqual(NSTextAlignmentFromTextAlign(@"end", LayoutDirection::RightToLeft), NSTextAlignmentLeft);
 }
 
+- (void)testUndeclaredTextAlignmentResolvesWithLayoutDirection
+{
+  NSParagraphStyle *leftToRight = ParagraphStyleFromLayoutDirection(LayoutDirection::LeftToRight);
+  XCTAssertNotNil(leftToRight);
+  XCTAssertEqual(leftToRight.alignment, NSTextAlignmentLeft);
+
+  NSParagraphStyle *rightToLeft = ParagraphStyleFromLayoutDirection(LayoutDirection::RightToLeft);
+  XCTAssertNotNil(rightToLeft);
+  XCTAssertEqual(rightToLeft.alignment, NSTextAlignmentRight);
+}
+
+- (void)testUndeclaredTextAlignmentWithoutLayoutDirectionStaysNatural
+{
+  XCTAssertNil(ParagraphStyleFromLayoutDirection(std::nullopt));
+}
+
 - (void)testSamenessOfEmptyAttributedStrings
 {
   NSAttributedString *attributedString1 = [[NSAttributedString alloc] initWithString:@""];
diff --git a/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTAttributedTextUtils.mm b/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTAttributedTextUtils.mm
index 95ff5a0d180e..ebebb33ff749 100644
--- a/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTAttributedTextUtils.mm
+++ b/packages/react-native/ReactCommon/react/renderer/textlayoutmanager/platform/ios/react/renderer/textlayoutmanager/RCTAttributedTextUtils.mm
@@ -218,7 +218,7 @@ inline static CGFloat RCTEffectiveFontSizeMultiplierFromTextAttributes(const Tex
   NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
   BOOL isParagraphStyleUsed = NO;
   const bool isRTL = textAttributes.layoutDirection == LayoutDirection::RightToLeft;
-  if (textAttributes.alignment.has_value() || isRTL) {
+  if (textAttributes.alignment.has_value() || textAttributes.layoutDirection.has_value()) {
     TextAlignment textAlignment =
         RCTResolveTextAlignment(textAttributes.alignment.value_or(TextAlignment::Natural), isRTL);