APP-2983: Fix RTL post alignment on native (#11600)

src/lib/strings/__tests__/text-direction.test.ts

@@ -0,0 +1,24 @@
+import {describe, expect, it} from '@jest/globals'
+
+import {isRTLText} from '../text-direction'
+
+describe('isRTLText', () => {
+  it('recognizes right-to-left text', () => {
+    expect(isRTLText('עברית')).toBe(true)
+    expect(isRTLText('العربية')).toBe(true)
+  })
+
+  it('recognizes left-to-right text', () => {
+    expect(isRTLText('English')).toBe(false)
+  })
+
+  it('uses the first strong directional character', () => {
+    expect(isRTLText('  123 🦋 עברית English')).toBe(true)
+    expect(isRTLText('  123 🦋 English עברית')).toBe(false)
+  })
+
+  it('defaults to left-to-right when there are no strong characters', () => {
+    expect(isRTLText('123 🦋 ...')).toBe(false)
+    expect(isRTLText('')).toBe(false)
+  })
+})

src/lib/strings/text-direction.native.ts

@@ -0,0 +1,17 @@
+import bidiFactory from 'bidi-js'
+
+const bidi = bidiFactory()
+
+/**
+ * Checks the first strong directional character, matching HTML `dir="auto"`.
+ */
+export function isRTLText(text: string) {
+  for (const character of text) {
+    const type = bidi.getBidiCharTypeName(character)
+
+    if (type === 'R' || type === 'AL') return true
+    if (type === 'L') return false
+  }
+
+  return false
+}

src/lib/strings/text-direction.web.ts

@@ -0,0 +1,7 @@
+/**
+ * React Native Web sets `dir="auto"` on root Text elements, so the browser
+ * handles direction detection without JavaScript.
+ */
+export function isRTLText(_text: string) {
+  return false
+}