converted java tests to kotlin

app/src/androidTest/java/com/delet_dis/bubbles/ExampleInstrumentedTest.kt

@@ -0,0 +1,22 @@
+package com.delet_dis.bubbles
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import org.junit.Assert
+import org.junit.Test
+import org.junit.runner.RunWith
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * @see [Testing documentation](http://d.android.com/tools/testing)
+ */
+@RunWith(AndroidJUnit4::class)
+class ExampleInstrumentedTest {
+  @Test
+  fun useAppContext() {
+    // Context of the app under test.
+    val appContext = InstrumentationRegistry.getInstrumentation().targetContext
+    Assert.assertEquals("com.delet_dis.bubbles", appContext.packageName)
+  }
+}

app/src/test/java/com/delet_dis/bubbles/ExampleUnitTest.kt

@@ -0,0 +1,16 @@
+package com.delet_dis.bubbles
+
+import org.junit.Assert
+import org.junit.Test
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see [Testing documentation](http://d.android.com/tools/testing)
+ */
+class ExampleUnitTest {
+  @Test
+  fun addition_isCorrect() {
+    Assert.assertEquals(4, (2 + 2).toLong())
+  }
+}