refactor: convert services unit tests to kotlin (#1239)

Author: fractalwrench

services/src/test/java/io/opentelemetry/android/internal/services/applifecycle/ApplicationStateWatcherTest.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.android.internal.services.applifecycle
+
+import androidx.core.app.ComponentActivity
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+import org.mockito.Mock
+import org.mockito.Mockito
+import org.mockito.junit.jupiter.MockitoExtension
+
+@ExtendWith(MockitoExtension::class)
+internal class ApplicationStateWatcherTest {
+    @Mock
+    private lateinit var activity: ComponentActivity
+
+    @Mock
+    private lateinit var listener1: ApplicationStateListener
+
+    @Mock
+    private lateinit var listener2: ApplicationStateListener
+
+    private lateinit var underTest: ApplicationStateWatcher
+
+    @BeforeEach
+    fun setUp() {
+        underTest = ApplicationStateWatcher()
+        underTest.registerListener(listener1)
+        underTest.registerListener(listener2)
+    }
+
+    @Test
+    fun appForegrounded() {
+        underTest.onStart(activity)
+
+        val io = Mockito.inOrder(listener1, listener2)
+        io.verify(listener1).onApplicationForegrounded()
+        io.verify(listener2).onApplicationForegrounded()
+        io.verifyNoMoreInteractions()
+    }
+
+    @Test
+    fun appBackgrounded() {
+        underTest.onStart(activity)
+        underTest.onStop(activity)
+
+        val io = Mockito.inOrder(listener1, listener2)
+        io.verify(listener1).onApplicationForegrounded()
+        io.verify(listener2).onApplicationForegrounded()
+        io.verify(listener1).onApplicationBackgrounded()
+        io.verify(listener2).onApplicationBackgrounded()
+        io.verifyNoMoreInteractions()
+    }
+
+    @Test
+    fun closing() {
+        underTest.close()
+
+        underTest.onStart(activity)
+        underTest.onStop(activity)
+
+        Mockito.verifyNoInteractions(listener1, listener2)
+    }
+}