Unit test added for Usecase and repository

Author: Kishan Kumar Maurya

app/src/test/java/com/example/githubfirebaseissue/repository/GithubRepositoryImplTest.kt

@@ -0,0 +1,112 @@
+package com.example.githubfirebaseissue.repository
+
+import com.example.githubfirebaseissue.api.GithubApi
+import com.example.githubfirebaseissue.model.Comment
+import com.example.githubfirebaseissue.model.Issue
+import com.example.githubfirebaseissue.testutil.Rx2SchedulersOverrideRule
+import com.nhaarman.mockitokotlin2.verify
+import io.reactivex.Single
+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.`when`
+import org.mockito.Mockito.mock
+import org.mockito.junit.MockitoJUnitRunner
+import retrofit2.HttpException
+import retrofit2.Response
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
+import okhttp3.ResponseBody.Companion.toResponseBody
+
+
+@RunWith(MockitoJUnitRunner::class)
+class GithubRepositoryImplTest {
+
+    @JvmField
+    @Rule
+    val rx2SchedulersOverrideRule = Rx2SchedulersOverrideRule()
+
+    private lateinit var repo: GithubRepository
+
+    @Mock
+    private lateinit var endpoint: GithubApi
+
+    @Before
+    fun setUp() {
+        repo = GithubRepositoryImpl(endpoint)
+    }
+
+    @Test
+    fun `should return issues when fetching FireBase ios issue`() {
+        val expectedResponse = listOf(mock(Issue::class.java))
+        `when`(endpoint.getFireBaseIosIssues()).thenReturn(Single.create {
+            it.onSuccess(
+                expectedResponse
+            )
+        })
+        endpoint.getFireBaseIosIssues()
+            .test()
+            .assertComplete()
+            .assertNoErrors()
+            .assertValue(expectedResponse)
+    }
+
+
+    @Test
+    fun `should return error when fetching FireBase ios issue`() {
+
+        val body = Response.error<Issue>(
+            400,
+            "{\"key\":[\"something went wrong\"]}".toResponseBody("application/json".toMediaTypeOrNull())
+        )
+        val exception = HttpException(body)
+
+        `when`(endpoint.getFireBaseIosIssues()).thenReturn(Single.error(exception))
+        repo.getFireBaseIosIssues()
+            .test()
+            .assertValueCount(0)
+            .assertError { it is HttpException }
+
+        verify(endpoint).getFireBaseIosIssues()
+
+    }
+
+
+    @Test
+    fun `should return comments when fetching FireBase ios issue comments`() {
+        val expectedResponse = listOf(mock(Comment::class.java))
+        `when`(endpoint.getFireBaseIosUserComments(1234)).thenReturn(Single.create {
+            it.onSuccess(
+                expectedResponse
+            )
+        })
+        endpoint.getFireBaseIosUserComments(1234)
+            .test()
+            .assertComplete()
+            .assertNoErrors()
+            .assertValue(expectedResponse)
+    }
+
+
+    @Test
+    fun `should return error when fetching FireBase ios issue comments`() {
+
+        val body = Response.error<Comment>(
+            400,
+            "{\"key\":[\"something went wrong\"]}".toResponseBody("application/json".toMediaTypeOrNull())
+        )
+        val exception = HttpException(body)
+
+        `when`(endpoint.getFireBaseIosUserComments(1234)).thenReturn(Single.error(exception))
+        repo.getFireBaseIosUserComments(1234)
+            .test()
+            .assertValueCount(0)
+            .assertError { it is HttpException }
+
+        verify(endpoint).getFireBaseIosUserComments(1234)
+
+    }
+
+}

app/src/test/java/com/example/githubfirebaseissue/testutil/Rx2SchedulersOverrideRule.kt

@@ -0,0 +1,28 @@
+package com.example.githubfirebaseissue.testutil
+
+import io.reactivex.android.plugins.RxAndroidPlugins
+import io.reactivex.plugins.RxJavaPlugins
+import io.reactivex.schedulers.Schedulers
+import org.junit.rules.TestRule
+import org.junit.runner.Description
+import org.junit.runners.model.Statement
+
+class Rx2SchedulersOverrideRule : TestRule {
+
+    override fun apply(base: Statement?, description: Description?): Statement =
+        object : Statement() {
+            override fun evaluate() {
+                RxJavaPlugins.setIoSchedulerHandler { _ -> Schedulers.trampoline() }
+                RxJavaPlugins.setComputationSchedulerHandler { _ -> Schedulers.trampoline() }
+                RxJavaPlugins.setNewThreadSchedulerHandler { _ -> Schedulers.trampoline() }
+                RxAndroidPlugins.setInitMainThreadSchedulerHandler { _ -> Schedulers.trampoline() }
+
+                try {
+                    base?.evaluate()
+                } finally {
+                    RxJavaPlugins.reset()
+                    RxAndroidPlugins.reset()
+                }
+            }
+        }
+}

app/src/test/java/com/example/githubfirebaseissue/usecase/GetFireBaseIssueUseCaseImplTest.kt

@@ -0,0 +1,87 @@
+package com.example.githubfirebaseissue.usecase
+
+import com.example.githubfirebaseissue.model.Comment
+import com.example.githubfirebaseissue.model.Issue
+import com.example.githubfirebaseissue.repository.GithubRepositoryImpl
+import com.example.githubfirebaseissue.testutil.Rx2SchedulersOverrideRule
+import io.reactivex.Single
+import junit.framework.Assert
+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.MockitoJUnitRunner
+
+
+@RunWith(MockitoJUnitRunner::class)
+class GetFireBaseIssueUseCaseImplTest {
+
+
+    @JvmField
+    @Rule
+    val rx2SchedulersOverrideRule = Rx2SchedulersOverrideRule()
+
+    private lateinit var usecase: GetFireBaseIssueUseCase
+
+    @Mock
+    private lateinit var repo: GithubRepositoryImpl
+
+    @Before
+    fun setUp() {
+        usecase = GetFireBaseIssueUseCaseImpl(repo)
+    }
+
+
+    @Test
+    fun `should return FireBase ios issues successfully`() {
+
+        val issueResponse = mock(Issue::class.java)
+        val issueList = mutableListOf<Issue>()
+        issueList.add(issueResponse)
+        `when`(repo.getFireBaseIosIssues()).thenReturn(Single.just(issueList.toList()))
+
+        usecase.getFireBaseIosIssues()
+            .test()
+            .assertComplete()
+            .assertValueCount(1)
+            .assertValue {
+                Assert.assertEquals(issueList, it)
+                true
+            }
+
+        verify(repo).getFireBaseIosIssues()
+        verifyNoMoreInteractions(repo)
+
+    }
+
+
+    @Test
+    fun `should return FireBase ios comment successfully`() {
+
+        val commentResponse = mock(Comment::class.java)
+        val commentList = mutableListOf<Comment>()
+        commentList.add(commentResponse)
+
+        val number = 1234
+        `when`(repo.getFireBaseIosUserComments(number)).thenReturn(Single.just(commentList.toList()))
+
+        usecase.getFireBaseIssuesComments(number)
+            .test()
+            .assertComplete()
+            .assertValueCount(1)
+            .assertValue {
+                Assert.assertEquals(commentList, it)
+                true
+            }
+
+        verify(repo).getFireBaseIosUserComments(number)
+        verifyNoMoreInteractions(repo)
+
+    }
+
+
+
+}