Updated on 2026-08-14

domain/address-book/src/main/kotlin/com/tangem/domain/addressbook/model/ContactName.kt

@@ -3,6 +3,7 @@ package com.tangem.domain.addressbook.model
 import arrow.core.Either
 import arrow.core.raise.either
 import arrow.core.raise.ensure
+import com.tangem.domain.addressbook.model.ContactName.Companion.invoke
 import kotlinx.serialization.Serializable
 
 /**
@@ -31,11 +32,24 @@ data class ContactName private constructor(val value: String) {
 
     companion object {
 
-        const val MIN_LENGTH = 1
+        private const val MIN_LENGTH = 1
         const val MAX_LENGTH = 50
 
-        /** Letters, numbers and spaces only — forbids emoji, new lines, tabs, special symbols and html/scripts. */
-        private val allowedPattern = Regex("^[\\p{L}\\p{N} ]+$")
+        /**
+         * Allows letters of any locale (`\p{L}`) and their combining marks (`\p{M}`, which also covers emoji
+         * variation selectors and keycap marks), digits (`\p{N}`), a regular space, and emoji — symbols (`\p{So}`,
+         * including flags / regional indicators), emoji skin-tone modifiers (`\p{Sk}`) and the zero-width joiner
+         * (U+200D) used in emoji sequences.
+         *
+         * Everything else is rejected, which covers the forbidden set: line breaks, tabs and other control
+         * characters, invisible/format unicode (zero-width spaces, BOM, …), exotic spaces, and HTML/script symbols.
+         *
+         * The leading lookahead requires at least one visible "base" character (letter / digit / emoji symbol), so a
+         * name made up only of zero-width joiners, combining marks, modifiers or spaces (i.e. effectively invisible)
+         * is rejected.
+         */
+        private val allowedPattern =
+            Regex("^(?=.*[\\p{L}\\p{N}\\p{So}])[\\p{L}\\p{M}\\p{N}\\p{So}\\p{Sk}\\u0020\\u200D]+$")
 
         operator fun invoke(value: String): Either<Error, ContactName> = either {
             val trimmed = value.trim()

domain/address-book/src/test/kotlin/com/tangem/domain/addressbook/model/ContactNameTest.kt

@@ -39,8 +39,33 @@ class ContactNameTest {
     }
 
     @Test
-    fun `emoji is rejected`() {
-        assertThat(ContactName("Alice 😀").leftOrNull()).isEqualTo(ContactName.Error.InvalidCharacters)
+    fun `simple emoji is accepted`() {
+        assertThat(ContactName("Alice 😀").isRight()).isTrue()
+    }
+
+    @Test
+    fun `emoji-only name is accepted`() {
+        assertThat(ContactName("😀").isRight()).isTrue()
+    }
+
+    @Test
+    fun `flag emoji is accepted`() {
+        assertThat(ContactName("Team 🇺🇸").isRight()).isTrue()
+    }
+
+    @Test
+    fun `zwj emoji sequence is accepted`() {
+        assertThat(ContactName("Family 👨‍👩‍👧").isRight()).isTrue()
+    }
+
+    @Test
+    fun `emoji with variation selector is accepted`() {
+        assertThat(ContactName("Love ❤️").isRight()).isTrue()
+    }
+
+    @Test
+    fun `non-latin letters are accepted`() {
+        assertThat(ContactName("Алёша 大阪").isRight()).isTrue()
     }
 
     @Test
@@ -53,6 +78,16 @@ class ContactNameTest {
         assertThat(ContactName("Ali\tce").leftOrNull()).isEqualTo(ContactName.Error.InvalidCharacters)
     }
 
+    @Test
+    fun `zero-width space is rejected`() {
+        assertThat(ContactName("Ali\u200Bce").leftOrNull()).isEqualTo(ContactName.Error.InvalidCharacters)
+    }
+
+    @Test
+    fun `non-breaking space is rejected`() {
+        assertThat(ContactName("Ali\u00A0ce").leftOrNull()).isEqualTo(ContactName.Error.InvalidCharacters)
+    }
+
     @Test
     fun `html script is rejected`() {
         assertThat(ContactName("<script>alert(1)</script>").leftOrNull())