testing set usecase

Author: pablobaldez

features/finances/impl/src/main/kotlin/br/com/mob1st/features/finances/impl/domain/usecases/SetCategoryUseCase.kt

@@ -10,9 +10,7 @@ internal class SetCategoryUseCase(
     private val analyticsReporter: AnalyticsReporter,
     private val eventFactory: SetCategoryEventFactory,
 ) {
-    suspend operator fun invoke(
-        category: Category,
-    ) {
+    suspend operator fun invoke(category: Category) {
         if (category.id.isWritten()) {
             categoryRepository.set(category)
         } else {

features/finances/impl/src/test/kotlin/br/com/mob1st/features/finances/impl/domain/usecases/SetCategoryUseCaseTest.kt

@@ -1,11 +1,97 @@
 package br.com.mob1st.features.finances.impl.domain.usecases
 
+import br.com.mob1st.core.observability.events.AnalyticsEvent
+import br.com.mob1st.core.observability.events.AnalyticsReporter
+import br.com.mob1st.features.finances.impl.domain.entities.Category
+import br.com.mob1st.features.finances.impl.domain.events.SetCategoryEventFactory
+import br.com.mob1st.features.finances.impl.domain.fixtures.category
+import br.com.mob1st.features.finances.impl.domain.infra.repositories.CategoryRepository
+import io.kotest.property.Arb
+import io.kotest.property.arbitrary.next
+import io.mockk.coEvery
+import io.mockk.coVerify
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import kotlinx.coroutines.test.runTest
+import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
 
 class SetCategoryUseCaseTest {
     private lateinit var useCase: SetCategoryUseCase
+    private lateinit var categoryRepository: CategoryRepository
+    private lateinit var analyticsReporter: AnalyticsReporter
+    private lateinit var eventFactory: SetCategoryEventFactory
+
+    @BeforeEach
+    fun setUp() {
+        categoryRepository = mockk(relaxed = true)
+        analyticsReporter = mockk(relaxed = true)
+        eventFactory = mockk()
+        every { eventFactory.create(any()) } returns AnalyticsEvent(name = "fake")
+        useCase = SetCategoryUseCase(
+            categoryRepository = categoryRepository,
+            analyticsReporter = analyticsReporter,
+            eventFactory = eventFactory,
+        )
+    }
+
+    @Test
+    fun `GIVEN an existing category WHEN set THEN assert it is updated And event is sent`() = runTest {
+        val existingCategory = Arb.category().next().copy(
+            id = Category.Id(1),
+        )
+        useCase(existingCategory)
+        coVerify(exactly = 1) {
+            categoryRepository.set(existingCategory)
+            eventFactory.create(existingCategory)
+            analyticsReporter.report(AnalyticsEvent(name = "fake"))
+        }
+
+        coVerify(exactly = 0) {
+            categoryRepository.add(any())
+        }
+    }
+
+    @Test
+    fun `GIVEN a new category WHEN set THEN assert it is added And event is sent`() = runTest {
+        val newCategory = Arb.category().next().copy(
+            id = Category.Id(),
+        )
+        useCase(newCategory)
+        coVerify(exactly = 1) {
+            categoryRepository.add(newCategory)
+            eventFactory.create(newCategory)
+            analyticsReporter.report(AnalyticsEvent(name = "fake"))
+        }
+
+        coVerify(exactly = 0) {
+            categoryRepository.set(any())
+        }
+    }
+
+    @Test
+    fun `GIVEN a failure WHEN set new category THEN assert error is thrown And event is not sent`() = runTest {
+        coEvery { categoryRepository.add(any()) } throws Exception()
+        assertThrows<Exception> {
+            useCase(Arb.category().next().copy(id = Category.Id()))
+        }
+        verify(exactly = 0) {
+            eventFactory.create(any())
+            analyticsReporter.report(any())
+        }
+    }
 
     @Test
-    fun `GIVEN a category WHEN update THEN`() {
+    fun `GIVEN a failure WHEN set existing category THEN assert error is thrown And event is not sent`() = runTest {
+        coEvery { categoryRepository.set(any()) } throws Exception()
+        assertThrows<Exception> {
+            useCase(Arb.category().next().copy(id = Category.Id(1)))
+        }
+        verify(exactly = 0) {
+            eventFactory.create(any())
+            analyticsReporter.report(any())
+        }
     }
 }