Write ViewModel Tests

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Tue Jul 14 15:56:55 IST 2020
+#Tue Jan 25 12:20:13 IST 2022
 distributionBase=GRADLE_USER_HOME
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.3-bin.zip
 distributionPath=wrapper/dists
-zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-bin.zip
+zipStoreBase=GRADLE_USER_HOME

ui-githubrepos/build.gradle.kts

@@ -106,4 +106,5 @@ dependencies {
   testImplementation(TestLib.ROBO_ELECTRIC)
   testImplementation(TestLib.COROUTINES)
   testImplementation(TestLib.MOCKK)
+  testImplementation(TestLib.TURBINE)
 }

ui-githubrepos/src/test/java/com/mutualmobile/feat/githubrepos/ui/github/repolist/GithubReposVMTest.kt

@@ -0,0 +1,109 @@
+package com.mutualmobile.feat.githubrepos.ui.github.repolist
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule
+import androidx.paging.PagingData
+import app.cash.turbine.test
+import com.mutualmobile.feat.githubrepos.ui.model.UIRepoMapper
+import com.mutualmobile.feat.githubrepos.utils.getOrAwaitValue
+import com.mutualmobile.praxis.data.repository.GithubRepoImpl
+import com.mutualmobile.praxis.domain.model.DOMOwner
+import com.mutualmobile.praxis.domain.model.DOMRepo
+import com.mutualmobile.praxis.domain.usecases.GetGithubTrendingReposUseCase
+import io.mockk.MockKAnnotations
+import io.mockk.coEvery
+import io.mockk.impl.annotations.MockK
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.flowOf
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.rules.TestRule
+
+@ExperimentalCoroutinesApi
+class GithubReposVMTest {
+
+    /**
+     * Important for your test's execution while testing LiveData.
+     * Fixes error message: "Android looper not mocked"
+     */
+    @get:Rule
+    var rule: TestRule = InstantTaskExecutorRule()
+
+    lateinit var githubReposVM: GithubReposVM
+
+    @MockK
+    lateinit var githubRepoImpl: GithubRepoImpl
+
+    lateinit var githubTrendingReposUseCase: GetGithubTrendingReposUseCase
+
+    @MockK
+    lateinit var uiRepoMapper: UIRepoMapper
+
+    @Before
+    fun setUp() {
+        MockKAnnotations.init(this, true)
+        Dispatchers.setMain(StandardTestDispatcher())
+        uiRepoMapper = UIRepoMapper()
+    }
+
+    @After
+    fun tearDown() {
+        Dispatchers.resetMain()
+    }
+
+    @Test
+    fun `test that trendingGithubRepos() completes without exception`() = runTest {
+        launch {
+            val testRepo = PagingData.from(
+                listOf(
+                    DOMRepo(
+                        id = 0,
+                        name = "Test",
+                        fullName = "Test",
+                        description = "Test",
+                        url = "Test",
+                        stars = 0,
+                        forks = 0,
+                        language = "Test",
+                        watchers = 0,
+                        owner = DOMOwner(
+                            id = 0,
+                            login = "Test",
+                            avatarUrl = "Test"
+                        ),
+                        createDate = "Test",
+                        updateDate = "Test",
+                        openIssues = 0
+                    )
+                )
+            )
+
+            coEvery {
+                githubRepoImpl.getTrendingRepos("flutter")
+            } returns flowOf(testRepo)
+
+            githubTrendingReposUseCase = GetGithubTrendingReposUseCase(githubRepoImpl)
+
+            githubReposVM = GithubReposVM(
+                githubTrendingReposUseCase,
+                uiRepoMapper
+            )
+
+            githubReposVM.getGitHubTrendingRepos()
+            delay(1) // Because we need our liveData to be assigned first before testing
+
+            githubReposVM.reposFlowLiveData.getOrAwaitValue().test {
+                assert(awaitItem() == testRepo)
+                cancelAndConsumeRemainingEvents()
+            }
+        }
+    }
+}

ui-githubrepos/src/test/java/com/mutualmobile/feat/githubrepos/utils/LiveDataUtil.kt

@@ -0,0 +1,63 @@
+package com.mutualmobile.feat.githubrepos.utils
+
+/*
+ * Copyright (C) 2019 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.
+ */
+
+import androidx.annotation.VisibleForTesting
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.Observer
+import java.util.concurrent.CountDownLatch
+import java.util.concurrent.TimeUnit
+import java.util.concurrent.TimeoutException
+
+/**
+ * Gets the value of a [LiveData] or waits for it to have one, with a timeout.
+ *
+ * Use this extension from host-side (JVM) tests. It's recommended to use it alongside
+ * `InstantTaskExecutorRule` or a similar mechanism to execute tasks synchronously.
+ */
+@VisibleForTesting(otherwise = VisibleForTesting.NONE)
+fun <T> LiveData<T>.getOrAwaitValue(
+    time: Long = 2,
+    timeUnit: TimeUnit = TimeUnit.SECONDS,
+    afterObserve: () -> Unit = {}
+): T {
+    var data: T? = null
+    val latch = CountDownLatch(1)
+    val observer = object : Observer<T> {
+        override fun onChanged(o: T?) {
+            data = o
+            latch.countDown()
+            this@getOrAwaitValue.removeObserver(this)
+        }
+    }
+    this.observeForever(observer)
+
+    try {
+        afterObserve.invoke()
+
+        // Don't wait indefinitely if the LiveData is not set.
+        if (!latch.await(time, timeUnit)) {
+            throw TimeoutException("LiveData value was never set.")
+        }
+
+    } finally {
+        this.removeObserver(observer)
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    return data as T
+}

ui-jokes/build.gradle.kts

@@ -97,4 +97,5 @@ dependencies {
   testImplementation(TestLib.ROBO_ELECTRIC)
   testImplementation(TestLib.COROUTINES)
   testImplementation(TestLib.MOCKK)
+  testImplementation(TestLib.TURBINE)
 }

ui-jokes/src/test/java/com/mutualmobile/feat/jokes/ui/joke/home/HomeVMTest.kt

@@ -0,0 +1,99 @@
+package com.mutualmobile.feat.jokes.ui.joke.home
+
+import app.cash.turbine.test
+import com.mutualmobile.feat.jokes.ui.model.UIJokeMapper
+import com.mutualmobile.praxis.data.repository.JokesRepoImpl
+import com.mutualmobile.praxis.domain.SafeResult
+import com.mutualmobile.praxis.domain.model.DOMJoke
+import com.mutualmobile.praxis.domain.model.DOMJokeList
+import com.mutualmobile.praxis.domain.usecases.GetFiveRandomJokesUseCase
+import com.mutualmobile.praxis.navigator.ComposeNavigator
+import io.mockk.MockKAnnotations
+import io.mockk.coEvery
+import io.mockk.impl.annotations.MockK
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.emptyFlow
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+
+@ExperimentalCoroutinesApi
+class HomeVMTest {
+
+    private val uiJokesMapper = UIJokeMapper()
+
+    @MockK
+    private lateinit var navigator: ComposeNavigator
+    private lateinit var getFiveRandomJokesUseCase: GetFiveRandomJokesUseCase
+    private lateinit var homeVM: HomeVM
+
+    @MockK
+    private lateinit var jokesRepoImpl: JokesRepoImpl
+
+    @Before
+    fun setUp() {
+        MockKAnnotations.init(this, true)
+        Dispatchers.setMain(StandardTestDispatcher())
+    }
+
+    @After
+    fun tearDown() {
+        Dispatchers.resetMain()
+    }
+
+    @Test
+    fun `test that loadJokes() completes on success response`() = runTest {
+
+        // This is mocking
+        coEvery {
+            navigator.observeResult<String>(any())
+        } returns emptyFlow()
+
+        coEvery {
+            jokesRepoImpl.getFiveRandomJokes()
+        } returns SafeResult.Success(
+            data = DOMJokeList(
+                type = "success",
+                DOMJokes = listOf(
+                    DOMJoke(0, "Test Joke")
+                )
+            )
+        )
+
+        getFiveRandomJokesUseCase = GetFiveRandomJokesUseCase(jokesRepoImpl)
+
+        homeVM = HomeVM(getFiveRandomJokesUseCase, uiJokesMapper, navigator)
+
+        homeVM.viewState.test {
+            assert(awaitItem() is HomeViewState.Loading)
+            assert(awaitItem() is HomeViewState.ShowJokes)
+        }
+    }
+
+    @Test
+    fun `test that loadJokes() fails on failed response`() = runTest {
+
+        // This is mocking
+        coEvery {
+            navigator.observeResult<String>(any())
+        } returns emptyFlow()
+
+        coEvery {
+            jokesRepoImpl.getFiveRandomJokes()
+        } returns SafeResult.Failure()
+
+        getFiveRandomJokesUseCase = GetFiveRandomJokesUseCase(jokesRepoImpl)
+
+        homeVM = HomeVM(getFiveRandomJokesUseCase, uiJokesMapper, navigator)
+
+        homeVM.viewState.test {
+            assert(awaitItem() is HomeViewState.Loading)
+            assert(awaitItem() is HomeViewState.Error)
+        }
+    }
+}

ui-jokes/src/test/java/com/mutualmobile/feat/jokes/ui/joke/jokedetails/JokeDetailVMTest.kt

@@ -0,0 +1,72 @@
+package com.mutualmobile.feat.jokes.ui.joke.jokedetails
+
+import androidx.lifecycle.SavedStateHandle
+import app.cash.turbine.test
+import com.mutualmobile.feat.jokes.ui.joke.InMemoryDataTemp
+import com.mutualmobile.feat.jokes.ui.model.UIJoke
+import io.mockk.MockKAnnotations
+import io.mockk.coEvery
+import io.mockk.impl.annotations.MockK
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import org.junit.After
+import org.junit.Before
+import org.junit.Test
+
+@ExperimentalCoroutinesApi
+class JokeDetailVMTest {
+
+    @MockK
+    lateinit var savedStateHandle: SavedStateHandle
+    lateinit var jokeDetailVM: JokeDetailVM
+
+    @Before
+    fun setUp() {
+        MockKAnnotations.init(this, true)
+        Dispatchers.setMain(StandardTestDispatcher())
+    }
+
+    @After
+    fun tearDown() {
+        Dispatchers.resetMain()
+    }
+
+    @Test
+    fun `test that uiState emits SuccessState on getting a non-null UIJoke`() = runTest {
+        launch {
+            coEvery {
+                savedStateHandle.get<Long>(any())
+            } returns 0
+
+            InMemoryDataTemp.jokes = listOf(
+                UIJoke(0, "TestJoke")
+            )
+            jokeDetailVM = JokeDetailVM(savedStateHandle)
+
+            jokeDetailVM.uiState.test {
+                assert(awaitItem() is JokeDetailVM.UiState.SuccessState)
+            }
+        }
+    }
+
+    @Test
+    fun `test that uiState emits LoadingState on getting a null UIJoke`() = runTest {
+        launch {
+            coEvery {
+                savedStateHandle.get<Long>(any())
+            } returns 0
+
+            InMemoryDataTemp.jokes = null
+            jokeDetailVM = JokeDetailVM(savedStateHandle)
+
+            jokeDetailVM.uiState.test {
+                assert(awaitItem() is JokeDetailVM.UiState.LoadingState)
+            }
+        }
+    }
+}