diff --git a/tools/systemfeatures/tests/Context.java b/tools/systemfeatures/tests/Context.java
new file mode 100644
index 0000000..630bc07
--- /dev/null
+++ b/tools/systemfeatures/tests/Context.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.content;
+
+import android.content.pm.PackageManager;
+
+/** Stub for testing. */
+public class Context {
+    /** @hide */
+    public PackageManager getPackageManager() {
+        return null;
+    }
+}
diff --git a/tools/systemfeatures/tests/PackageManager.java b/tools/systemfeatures/tests/PackageManager.java
new file mode 100644
index 0000000..645d500
--- /dev/null
+++ b/tools/systemfeatures/tests/PackageManager.java
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.content.pm;
+
+/** Stub for testing */
+public class PackageManager {
+    public static final String FEATURE_AUTO = "automotive";
+    public static final String FEATURE_VULKAN = "vulkan";
+    public static final String FEATURE_WATCH = "watch";
+    public static final String FEATURE_WIFI = "wifi";
+
+    /** @hide */
+    public boolean hasSystemFeature(String featureName, int version) {
+        return false;
+    }
+}
diff --git a/tools/systemfeatures/tests/SystemFeaturesGeneratorTest.java b/tools/systemfeatures/tests/SystemFeaturesGeneratorTest.java
new file mode 100644
index 0000000..547d2cb
--- /dev/null
+++ b/tools/systemfeatures/tests/SystemFeaturesGeneratorTest.java
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemfeatures;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import static org.mockito.Mockito.anyInt;
+import static org.mockito.Mockito.anyString;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnit;
+import org.mockito.junit.MockitoRule;
+
+@RunWith(JUnit4.class)
+public class SystemFeaturesGeneratorTest {
+
+    @Rule public final MockitoRule mockito = MockitoJUnit.rule();
+
+    @Mock private Context mContext;
+    @Mock private PackageManager mPackageManager;
+
+    @Before
+    public void setUp() {
+        when(mContext.getPackageManager()).thenReturn(mPackageManager);
+    }
+
+    @Test
+    public void testReadonlyDisabledNoDefinedFeatures() {
+        // Always report null for conditional queries if readonly codegen is disabled.
+        assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, 0)).isNull();
+        assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, 0)).isNull();
+        assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
+        assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
+        assertThat(RwNoFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
+    }
+
+    @Test
+    public void testReadonlyNoDefinedFeatures() {
+        // If no features are explicitly declared as readonly available, always report
+        // null for conditional queries.
+        assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, 0)).isNull();
+        assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, 0)).isNull();
+        assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
+        assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
+        assertThat(RoNoFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
+    }
+
+    @Test
+    public void testReadonlyDisabledWithDefinedFeatures() {
+        // Always fall back to the PackageManager for defined, explicit features queries.
+        when(mPackageManager.hasSystemFeature(PackageManager.FEATURE_WATCH, 0)).thenReturn(true);
+        assertThat(RwFeatures.hasFeatureWatch(mContext)).isTrue();
+
+        when(mPackageManager.hasSystemFeature(PackageManager.FEATURE_WATCH, 0)).thenReturn(false);
+        assertThat(RwFeatures.hasFeatureWatch(mContext)).isFalse();
+
+        when(mPackageManager.hasSystemFeature(PackageManager.FEATURE_WIFI, 0)).thenReturn(true);
+        assertThat(RwFeatures.hasFeatureWifi(mContext)).isTrue();
+
+        when(mPackageManager.hasSystemFeature(PackageManager.FEATURE_VULKAN, 0)).thenReturn(false);
+        assertThat(RwFeatures.hasFeatureVulkan(mContext)).isFalse();
+
+        when(mPackageManager.hasSystemFeature(PackageManager.FEATURE_AUTO, 0)).thenReturn(false);
+        assertThat(RwFeatures.hasFeatureAuto(mContext)).isFalse();
+
+        // For defined and undefined features, conditional queries should report null (unknown).
+        assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, 0)).isNull();
+        assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, 0)).isNull();
+        assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
+        assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
+        assertThat(RwFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
+    }
+
+    @Test
+    public void testReadonlyWithDefinedFeatures() {
+        // Always use the build-time feature version for defined, explicit feature queries, never
+        // falling back to the runtime query.
+        assertThat(RoFeatures.hasFeatureWatch(mContext)).isTrue();
+        assertThat(RoFeatures.hasFeatureWifi(mContext)).isTrue();
+        assertThat(RoFeatures.hasFeatureVulkan(mContext)).isFalse();
+        assertThat(RoFeatures.hasFeatureAuto(mContext)).isFalse();
+        verify(mPackageManager, never()).hasSystemFeature(anyString(), anyInt());
+
+        // For defined feature types, conditional queries should reflect the build-time versions.
+        // VERSION=1
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, -1)).isTrue();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, 0)).isTrue();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WATCH, 100)).isFalse();
+
+        // VERSION=0
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, -1)).isTrue();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, 0)).isTrue();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_WIFI, 100)).isFalse();
+
+        // VERSION=-1
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, -1)).isTrue();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isFalse();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 100)).isFalse();
+
+        // DISABLED
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, -1)).isFalse();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isFalse();
+        assertThat(RoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 100)).isFalse();
+
+        // For undefined types, conditional queries should report null (unknown).
+        assertThat(RoFeatures.maybeHasFeature("com.arbitrary.feature", -1)).isNull();
+        assertThat(RoFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
+        assertThat(RoFeatures.maybeHasFeature("com.arbitrary.feature", 100)).isNull();
+    }
+}