diff --git a/lib/ui/semantics.dart b/lib/ui/semantics.dart
index e0da396d8ec58..9167ae60d0f78 100644
--- a/lib/ui/semantics.dart
+++ b/lib/ui/semantics.dart
@@ -818,7 +818,7 @@ abstract class SemanticsUpdateBuilder {
     required String hint,
     required List<StringAttribute> hintAttributes,
     required String tooltip,
-    required TextDirection? textDirection,
+    required TextDirection textDirection,
     required Float64List transform,
     required Int32List childrenInTraversalOrder,
     required Int32List childrenInHitTestOrder,
@@ -888,7 +888,7 @@ base class _NativeSemanticsUpdateBuilder extends NativeFieldWrapperClass1 implem
     required String hint,
     required List<StringAttribute> hintAttributes,
     required String tooltip,
-    required TextDirection? textDirection,
+    required TextDirection textDirection,
     required Float64List transform,
     required Int32List childrenInTraversalOrder,
     required Int32List childrenInHitTestOrder,
@@ -927,7 +927,7 @@ base class _NativeSemanticsUpdateBuilder extends NativeFieldWrapperClass1 implem
       hint,
       hintAttributes,
       tooltip,
-      textDirection != null ? textDirection.index + 1 : 0,
+      textDirection.index + 1,
       transform,
       childrenInTraversalOrder,
       childrenInHitTestOrder,