From 3c57fcde327b7898f08139a01dc878d0dfc8b946 Mon Sep 17 00:00:00 2001
From: Joshua McCloskey <joshmccloskey@google.com>
Date: Thu, 7 Mar 2024 00:33:49 +0000
Subject: [PATCH] Fixed NPE in FingerprintEnrollIntro

Test: atest FingerprintEnrollIntroductionTest
Fixes: 317515741
Change-Id: Icc4e5cd4fbfea6828684ce6c8fc30acaabe5d315
---
 .../FingerprintEnrollIntroduction.java         |  3 +++
 .../FingerprintEnrollIntroductionTest.java     | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java b/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
index f92cfbf6696..26965fae758 100644
--- a/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
+++ b/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroduction.java
@@ -340,6 +340,9 @@ public class FingerprintEnrollIntroduction extends BiometricEnrollIntroduction {
             final List<FingerprintSensorPropertiesInternal> props =
                     mFingerprintManager.getSensorPropertiesInternal();
             // This will need to be updated for devices with multiple fingerprint sensors
+            if (props == null || props.isEmpty()) {
+                return R.string.fingerprint_intro_error_unknown;
+            }
             final int max = props.get(0).maxEnrollmentsPerUser;
             final int numEnrolledFingerprints =
                     mFingerprintManager.getEnrolledFingerprints(mUserId).size();
diff --git a/tests/robotests/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroductionTest.java b/tests/robotests/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroductionTest.java
index 89e70d2990f..99d519a9e0b 100644
--- a/tests/robotests/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroductionTest.java
+++ b/tests/robotests/src/com/android/settings/biometrics/fingerprint/FingerprintEnrollIntroductionTest.java
@@ -252,6 +252,24 @@ public class FingerprintEnrollIntroductionTest {
         assertThat(result).isEqualTo(R.string.fingerprint_intro_error_max);
     }
 
+    @Test
+    public void intro_CheckNullPropsReturnsErrorString() {
+        setupFingerprintEnrollIntroWith(newTokenOnlyIntent());
+        when(mFingerprintManager.getSensorPropertiesInternal()).thenReturn(null);
+        final int result = mFingerprintEnrollIntroduction.checkMaxEnrolled();
+
+        assertThat(result).isEqualTo(R.string.fingerprint_intro_error_unknown);
+    }
+
+    @Test
+    public void intro_CheckEmptyPropsReturnsErrorString() {
+        setupFingerprintEnrollIntroWith(newTokenOnlyIntent());
+        when(mFingerprintManager.getSensorPropertiesInternal()).thenReturn(List.of());
+        final int result = mFingerprintEnrollIntroduction.checkMaxEnrolled();
+
+        assertThat(result).isEqualTo(R.string.fingerprint_intro_error_unknown);
+    }
+
     @Test
     public void intro_CheckGenerateChallenge() {
         setupFingerprintEnrollIntroWith(newGkPwHandleAndFromSettingsIntent());