Hide roaming option when carriers force all networks as HOME networks

This change will hide roaming option in carrier's network setting
if the carrier overrrides the carrier config force_home_network_bool
to true.

Some carriers, like google Fi, has no concept of roaming. The carrier
config force_home_network_bool is overridden to true to treat all
cellular networks as home networks. There is no actually impact when
user turn on/off the roaming option in network setting. Leaving an
unused option just confuse many end users.

Bug: 79424760
Test: make && make RunSettingsRoboTests
Test: activate Fi service and make sure no roaming option
Test: activate VZW service and make sure roaming option is present
Test: override the cc config with adb command to make sure the roaming
option is always correctly shown/hidden on the cc key values

Change-Id: If6d0f7e3a5edea368b3a725afd9a2b4d1ad686ed

src/com/android/settings/network/telephony/RoamingPreferenceController.java

@@ -65,6 +65,16 @@ public class RoamingPreferenceController extends TelephonyTogglePreferenceContro
         mCarrierConfigManager = context.getSystemService(CarrierConfigManager.class);
     }
 
+    @Override
+    public int getAvailabilityStatus() {
+        final PersistableBundle carrierConfig = mCarrierConfigManager.getConfigForSubId(mSubId);
+        if (carrierConfig != null && carrierConfig.getBoolean(
+                CarrierConfigManager.KEY_FORCE_HOME_NETWORK_BOOL)) {
+            return CONDITIONALLY_UNAVAILABLE;
+        }
+        return AVAILABLE;
+    }
+
     @Override
     public void onStart() {
         if (mListener == null) {

tests/unit/src/com/android/settings/network/telephony/RoamingPreferenceControllerTest.java

@@ -16,6 +16,9 @@
 
 package com.android.settings.network.telephony;
 
+import static com.android.settings.core.BasePreferenceController.AVAILABLE;
+import static com.android.settings.core.BasePreferenceController.CONDITIONALLY_UNAVAILABLE;
+
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.mockito.ArgumentMatchers.anyBoolean;
@@ -92,7 +95,7 @@ public class RoamingPreferenceControllerTest {
     @Test
     public void getAvailabilityStatus_validSubId_returnAvailable() {
         assertThat(mController.getAvailabilityStatus()).isEqualTo(
-                BasePreferenceController.AVAILABLE);
+                AVAILABLE);
     }
 
     @Test
@@ -168,4 +171,29 @@ public class RoamingPreferenceControllerTest {
 
         verify(mPreference, never()).setEnabled(anyBoolean());
     }
+
+    @Test
+    public void getAvailabilityStatus_carrierConfigIsNull_shouldReturnAvailable() {
+        doReturn(null).when(mCarrierConfigManager).getConfigForSubId(SUB_ID);
+
+        assertThat(mController.getAvailabilityStatus()).isEqualTo(AVAILABLE);
+    }
+
+    @Test
+    public void getAvailabilityStatus_forceHomeNetworkIsFalse_shouldReturnAvailable() {
+        final PersistableBundle bundle = new PersistableBundle();
+        bundle.putBoolean(CarrierConfigManager.KEY_FORCE_HOME_NETWORK_BOOL, false);
+        doReturn(bundle).when(mCarrierConfigManager).getConfigForSubId(SUB_ID);
+
+        assertThat(mController.getAvailabilityStatus()).isEqualTo(AVAILABLE);
+    }
+
+    @Test
+    public void getAvailabilityStatus_forceHomeNetworkIsTrue_shouldReturnConditionallyAvailable() {
+        final PersistableBundle bundle = new PersistableBundle();
+        bundle.putBoolean(CarrierConfigManager.KEY_FORCE_HOME_NETWORK_BOOL, false);
+        doReturn(bundle).when(mCarrierConfigManager).getConfigForSubId(SUB_ID);
+
+        assertThat(mController.getAvailabilityStatus()).isEqualTo(CONDITIONALLY_UNAVAILABLE);
+    }
 }