Fix bug where switching to guest didn't work.

The cause was that we were using UserRecord.resolveId() which would
return UserHandle.USER_NULL when the record was for a guest. We now use
the raw ID in the UserRecord in this case.

Also, the logic is being moved from UserSwitcherControllerImpl which is
a temporary class meant to help us migrate from the old implementation
to the new and is thus not unit tested to UserInteractor, where we can
comfortably add unit tests in this CL.

Fix: 251740146, 251376342
Test: Issue no longer reproduces after this CL
Change-Id: Ib0cbb23d0f6111af7a2eb98278796c34a3e69209

packages/SystemUI/src/com/android/systemui/statusbar/policy/UserSwitcherControllerImpl.kt

@@ -30,7 +30,6 @@ import com.android.systemui.qs.user.UserSwitchDialogController
 import com.android.systemui.user.data.source.UserRecord
 import com.android.systemui.user.domain.interactor.GuestUserInteractor
 import com.android.systemui.user.domain.interactor.UserInteractor
-import com.android.systemui.user.legacyhelper.data.LegacyUserDataHelper
 import com.android.systemui.user.legacyhelper.ui.LegacyUserUiHelper
 import dagger.Lazy
 import java.io.PrintWriter
@@ -203,11 +202,7 @@ constructor(
         dialogShower: UserSwitchDialogController.DialogShower?,
     ) {
         if (useInteractor) {
-            if (LegacyUserDataHelper.isUser(record)) {
-                userInteractor.selectUser(record.resolveId())
-            } else {
-                userInteractor.executeAction(LegacyUserDataHelper.toUserActionModel(record))
-            }
+            userInteractor.onRecordSelected(record)
         } else {
             _oldImpl.onUserListItemClicked(record, dialogShower)
         }

packages/SystemUI/src/com/android/systemui/user/domain/interactor/UserInteractor.kt

@@ -390,6 +390,17 @@ constructor(
         guestUserInteractor.onDeviceBootCompleted()
     }
 
+    /** Switches to the user or executes the action represented by the given record. */
+    fun onRecordSelected(record: UserRecord) {
+        if (LegacyUserDataHelper.isUser(record)) {
+            // It's safe to use checkNotNull around record.info because isUser only returns true
+            // if record.info is not null.
+            selectUser(checkNotNull(record.info).id)
+        } else {
+            executeAction(LegacyUserDataHelper.toUserActionModel(record))
+        }
+    }
+
     /** Switches to the user with the given user ID. */
     fun selectUser(
         newlySelectedUserId: Int,

packages/SystemUI/tests/src/com/android/systemui/user/domain/interactor/UserInteractorRefactoredTest.kt

@@ -47,6 +47,7 @@ import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.junit.runners.JUnit4
+import org.mockito.ArgumentMatchers.anyBoolean
 import org.mockito.ArgumentMatchers.anyInt
 import org.mockito.Mockito.verify
 
@@ -72,6 +73,61 @@ class UserInteractorRefactoredTest : UserInteractorTest() {
         whenever(manager.canAddMoreUsers(any())).thenReturn(true)
     }
 
+    @Test
+    fun `onRecordSelected - user`() =
+        runBlocking(IMMEDIATE) {
+            val userInfos = createUserInfos(count = 3, includeGuest = false)
+            userRepository.setUserInfos(userInfos)
+            userRepository.setSelectedUserInfo(userInfos[0])
+            userRepository.setSettings(UserSwitcherSettingsModel(isUserSwitcherEnabled = true))
+
+            underTest.onRecordSelected(UserRecord(info = userInfos[1]))
+
+            verify(activityManager).switchUser(userInfos[1].id)
+            Unit
+        }
+
+    @Test
+    fun `onRecordSelected - switch to guest user`() =
+        runBlocking(IMMEDIATE) {
+            val userInfos = createUserInfos(count = 3, includeGuest = true)
+            userRepository.setUserInfos(userInfos)
+            userRepository.setSelectedUserInfo(userInfos[0])
+            userRepository.setSettings(UserSwitcherSettingsModel(isUserSwitcherEnabled = true))
+
+            underTest.onRecordSelected(UserRecord(info = userInfos.last()))
+
+            verify(activityManager).switchUser(userInfos.last().id)
+            Unit
+        }
+
+    @Test
+    fun `onRecordSelected - enter guest mode`() =
+        runBlocking(IMMEDIATE) {
+            val userInfos = createUserInfos(count = 3, includeGuest = false)
+            userRepository.setUserInfos(userInfos)
+            userRepository.setSelectedUserInfo(userInfos[0])
+            userRepository.setSettings(UserSwitcherSettingsModel(isUserSwitcherEnabled = true))
+
+            underTest.onRecordSelected(UserRecord(isGuest = true))
+
+            verify(manager).createGuest(any())
+            Unit
+        }
+
+    @Test
+    fun `onRecordSelected - action`() =
+        runBlocking(IMMEDIATE) {
+            val userInfos = createUserInfos(count = 3, includeGuest = true)
+            userRepository.setUserInfos(userInfos)
+            userRepository.setSelectedUserInfo(userInfos[0])
+            userRepository.setSettings(UserSwitcherSettingsModel(isUserSwitcherEnabled = true))
+
+            underTest.onRecordSelected(UserRecord(isAddSupervisedUser = true))
+
+            verify(activityStarter).startActivity(any(), anyBoolean())
+        }
+
     @Test
     fun `users - switcher enabled`() =
         runBlocking(IMMEDIATE) {