Destroy all Firebase instances before each tests

Author: fmasa

src/test/kotlin/AppTest.kt

@@ -5,7 +5,7 @@ import com.google.firebase.FirebasePlatform
 import com.google.firebase.initialize
 import org.junit.Test
 
-class AppTest {
+class AppTest : FirebaseTest() {
     @Test
     fun testInitialize() {
         FirebasePlatform.initializeFirebasePlatform(object : FirebasePlatform() {

src/test/kotlin/FirebaseTest.kt

@@ -0,0 +1,9 @@
+import com.google.firebase.FirebaseApp
+import org.junit.Before
+
+abstract class FirebaseTest {
+    @Before
+    fun beforeEach() {
+        FirebaseApp.clearInstancesForTest()
+    }
+}

src/test/kotlin/FirestoreTest.kt

@@ -11,7 +11,7 @@ import org.junit.Before
 import org.junit.Test
 import java.io.File
 
-class FirestoreTest {
+class FirestoreTest : FirebaseTest() {
     @Before
     fun initialize() {
         FirebasePlatform.initializeFirebasePlatform(object : FirebasePlatform() {