Extracted the duplicate test Realm setup to a test rule.

CodemateLtd · Feb 8, 2017 · cbf72dd · cbf72dd
1 parent f6ca81a
commit cbf72dd
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Showing 4 changed files with 54 additions and 36 deletions.
diff --git a/app/src/androidTest/java/com/codemate/koffeemate/data/local/CoffeeEventRepositoryTest.kt b/app/src/androidTest/java/com/codemate/koffeemate/data/local/CoffeeEventRepositoryTest.kt
@@ -19,36 +19,23 @@ package com.codemate.koffeemate.data.local
 import com.codemate.koffeemate.data.models.CoffeeBrewingEvent
 import com.codemate.koffeemate.data.models.User
 import io.realm.Realm
-import io.realm.RealmConfiguration
 import org.hamcrest.core.IsEqual.equalTo
-import org.junit.After
 import org.junit.Assert.assertThat
 import org.junit.Before
+import org.junit.Rule
 import org.junit.Test
 
 class CoffeeEventRepositoryTest {
-    val testConfig: RealmConfiguration = RealmConfiguration.Builder()
-            .name("test.realm")
-            .build()
-
     lateinit var coffeeEventRepository: RealmCoffeeEventRepository
 
+    @Rule @JvmField
+    val realmRule: RealmTestRule = RealmTestRule()
+
     @Before
     fun setUp() {
-        Realm.setDefaultConfiguration(testConfig)
-
-        val realm = Realm.getDefaultInstance()
-        realm.executeTransaction(Realm::deleteAll)
-        realm.close()
-
         coffeeEventRepository = RealmCoffeeEventRepository()
     }
 
-    @After
-    fun tearDown() {
-        Realm.deleteRealm(testConfig)
-    }
-
     @Test
     fun recordBrewingEvent_PersistsEventsInDatabase() {
         coffeeEventRepository.recordBrewingEvent()

diff --git a/app/src/androidTest/java/com/codemate/koffeemate/data/local/MigrationTest.kt b/app/src/androidTest/java/com/codemate/koffeemate/data/local/MigrationTest.kt
@@ -43,7 +43,7 @@ class MigrationTest {
     @Test
     fun testMigrationFromVersionZeroToOne() {
         val config = RealmConfiguration.Builder()
-                .name("migration-test.realm")
+                .name("test.realm")
                 .schemaVersion(1)
                 .migration(Migration())
                 .build()
@@ -82,6 +82,7 @@ class MigrationTest {
         assertThat(brewingEventWithUserId.user!!.last_updated, equalTo(brewingAccident.user!!.last_updated))
 
         realm.close()
+        Realm.deleteRealm(config)
     }
 
     @Throws(IOException::class)

diff --git a/app/src/androidTest/java/com/codemate/koffeemate/data/local/RealmTestRule.kt b/app/src/androidTest/java/com/codemate/koffeemate/data/local/RealmTestRule.kt
@@ -0,0 +1,44 @@
+package com.codemate.koffeemate.data.local
+
+import io.realm.Realm
+import io.realm.RealmConfiguration
+import org.junit.rules.ExternalResource
+import org.junit.runner.Description
+import org.junit.runners.model.Statement
+
+/**
+ * A JUnit Rule that sets up a test Realm database before each test,
+ * clears all data from it, and deletes the whole database file alltogether
+ * after the test completes.
+ *
+ * Usage:
+ *
+ * @Rule @JvmField
+ * val realmRule: RealmTestRule = RealmTestRule()
+ *
+ * The above assumes that your application logic that uses Realm always uses
+ * the default instance. Meaning that your code calls Realm.getDefaultInstance()
+ * and uses that for all database logic.
+ */
+class RealmTestRule : ExternalResource() {
+    val testConfig: RealmConfiguration = RealmConfiguration.Builder()
+            .name("test.realm")
+            .build()
+
+    override fun before() {
+        Realm.setDefaultConfiguration(testConfig)
+
+        with (Realm.getDefaultInstance()) {
+            executeTransaction(Realm::deleteAll)
+            close()
+        }
+    }
+
+    override fun apply(base: Statement?, description: Description?): Statement {
+        return super.apply(base, description)
+    }
+
+    override fun after() {
+        Realm.deleteRealm(testConfig)
+    }
+}
diff --git a/app/src/androidTest/java/com/codemate/koffeemate/data/local/UserRepositoryTest.kt b/app/src/androidTest/java/com/codemate/koffeemate/data/local/UserRepositoryTest.kt
@@ -17,40 +17,26 @@
 package com.codemate.koffeemate.data.local
 
 import com.codemate.koffeemate.data.models.User
-import io.realm.Realm
-import io.realm.RealmConfiguration
 import org.hamcrest.core.IsEqual.equalTo
-import org.junit.After
 import org.junit.Assert.assertThat
 import org.junit.Before
+import org.junit.Rule
 import org.junit.Test
 
 class UserRepositoryTest {
-    val testConfig: RealmConfiguration = RealmConfiguration.Builder()
-            .name("test.realm")
-            .build()
-
     val TEST_USERS_UNIQUE = listOf(User(id = "abc123"), User(id = "123abc"), User(id = "a1b2c3"))
     val TEST_USERS_DUPLICATE = listOf(User(id = "abc123"), User(id = "abc123"), User(id = "abc123"))
 
     lateinit var userRepository: UserRepository
 
+    @Rule @JvmField
+    val realmRule = RealmTestRule()
+
     @Before
     fun setUp() {
-        Realm.setDefaultConfiguration(testConfig)
-
-        val realm = Realm.getDefaultInstance()
-        realm.executeTransaction(Realm::deleteAll)
-        realm.close()
-
         userRepository = RealmUserRepository()
     }
 
-    @After
-    fun tearDown() {
-        Realm.deleteRealm(testConfig)
-    }
-
     @Test
     fun addAll_WhenUsersAreUnique_PersistsAllInDatabase() {
         userRepository.addAll(TEST_USERS_UNIQUE)