add unit-tests for presentation layer person feature

feature_person/src/test/java/com/mrozon/feature_person/presentation/ListPersonFragmentViewModelTest.kt

@@ -0,0 +1,77 @@
+package com.mrozon.feature_person.presentation
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule
+import androidx.lifecycle.Observer
+import com.mrozon.core_api.entity.Gender
+import com.mrozon.core_api.entity.Person
+import com.mrozon.core_api.providers.CoroutineContextProvider
+import com.mrozon.feature_person.data.CoroutineTestRule
+import com.mrozon.feature_person.data.PersonRepository
+import com.mrozon.utils.Event
+import com.mrozon.utils.network.Result
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.flowOf
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito
+import org.mockito.junit.MockitoJUnit
+import org.mockito.junit.MockitoRule
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import java.util.*
+import kotlin.coroutines.CoroutineContext
+
+@ExperimentalCoroutinesApi
+@RunWith(RobolectricTestRunner::class)
+@Config(manifest= Config.NONE)
+class ListPersonFragmentViewModelTest {
+
+    @get:Rule
+    val mockitoRule: MockitoRule = MockitoJUnit.rule()
+
+
+    @get:Rule
+    var coroutinesTestRule = CoroutineTestRule()
+
+    @get:Rule
+    val executorRule = InstantTaskExecutorRule()
+
+    @Mock
+    lateinit var observer: Observer<Event<Result<List<Person>>>>
+
+    @Mock
+    lateinit var repository: PersonRepository
+
+    lateinit var viewModel: ListPersonFragmentViewModel
+
+    @Before
+    fun setUp() {
+        viewModel = ListPersonFragmentViewModel(repository, TestCoroutineProvider())
+            .apply {
+                persons.observeForever(observer)
+            }
+    }
+
+    @Test
+    fun `refresh persons success`()  = coroutinesTestRule.runBlockingTest {
+        val person = Person(id=100, name="", gender = Gender.MALE, born = Date())
+        Mockito.`when`(repository.refreshPersons()).thenReturn(
+            flowOf(Result.loading(), Result.success(listOf(person)))
+        )
+
+        viewModel.refreshPersons()
+
+        Mockito.verify(observer).onChanged(Event(Result.loading()))
+        Mockito.verify(observer).onChanged(Event(Result.success(listOf(person))))
+    }
+
+}
+
+class TestCoroutineProvider: CoroutineContextProvider() {
+    override val Main: CoroutineContext = Dispatchers.Unconfined
+    override val IO: CoroutineContext = Dispatchers.Unconfined
+}