fix(android): guard deconstructRegistration against null Registration

android/build.gradle

@@ -68,6 +68,13 @@ android {
       }
     }
   }
+
+  testOptions {
+    unitTests {
+      includeAndroidResources = false
+      returnDefaultValues = true
+    }
+  }
 }
 
 repositories {
@@ -86,4 +93,7 @@ dependencies {
   implementation "com.google.firebase:firebase-messaging:24.1.2"
   implementation 'io.intercom.android:intercom-sdk:18.2.0'
   implementation 'io.intercom.android:intercom-sdk-ui:18.2.0'
+
+  testImplementation 'junit:junit:4.13.2'
+  testImplementation 'org.mockito:mockito-core:5.11.0'
 }

android/src/main/java/com/intercom/reactnative/IntercomHelpers.java

@@ -248,6 +248,9 @@ public static String getValueAsStringForKey(ReadableMap map, String key) {
 
   public static WritableMap deconstructRegistration(Registration registration) {
     WritableMap registrationMap = Arguments.createMap();
+    if (registration == null) {
+      return registrationMap;
+    }
     if (registration.getEmail() != null) {
       registrationMap.putString("email", registration.getEmail());
     }

android/src/test/java/com/intercom/reactnative/IntercomHelpersTest.java

@@ -0,0 +1,63 @@
+package com.intercom.reactnative;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.mockStatic;
+
+import com.facebook.react.bridge.Arguments;
+import com.facebook.react.bridge.JavaOnlyMap;
+import com.facebook.react.bridge.WritableMap;
+
+import io.intercom.android.sdk.identity.Registration;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.MockedStatic;
+
+public class IntercomHelpersTest {
+
+  private MockedStatic<Arguments> argumentsMock;
+
+  @Before
+  public void setUp() {
+    argumentsMock = mockStatic(Arguments.class);
+    argumentsMock.when(Arguments::createMap).thenAnswer(invocation -> new JavaOnlyMap());
+  }
+
+  @After
+  public void tearDown() {
+    argumentsMock.close();
+  }
+
+  // Regression guard for intercom/intercom#520691: a null Registration arrives here whenever
+  // Intercom.client().fetchLoggedInUserAttributes() returns null (no logged-in user, app
+  // re-launched after OS kill, etc.). Before the fix, this crashed the host process with
+  // NullPointerException on registration.getEmail().
+  @Test
+  public void deconstructRegistration_returnsEmptyMap_whenRegistrationIsNull() {
+    WritableMap result = IntercomHelpers.deconstructRegistration(null);
+
+    assertNotNull("expected an empty map, not null", result);
+    JavaOnlyMap map = (JavaOnlyMap) result;
+    assertFalse("expected no email key when registration is null", map.hasKey("email"));
+    assertFalse("expected no userId key when registration is null", map.hasKey("userId"));
+  }
+
+  @Test
+  public void deconstructRegistration_returnsBothFields_whenRegistrationIsFullyPopulated() {
+    Registration registration = new Registration()
+        .withEmail("test@example.com")
+        .withUserId("user-42");
+
+    WritableMap result = IntercomHelpers.deconstructRegistration(registration);
+    JavaOnlyMap map = (JavaOnlyMap) result;
+
+    assertTrue(map.hasKey("email"));
+    assertEquals("test@example.com", map.getString("email"));
+    assertTrue(map.hasKey("userId"));
+    assertEquals("user-42", map.getString("userId"));
+  }
+}