Add ktlint and mock unit test (#427)

Co-authored-by: Peixin Liu <peixinliu@Peixins-MacBook-Pro.local>

azure-communication-ui/chat/build.gradle

@@ -39,6 +39,23 @@ android {
             excludes += '/META-INF/{AL2.0,LGPL2.1}'
         }
     }
+
+    ktlint {
+        debug.set(false)
+        verbose.set(true)
+        android.set(true)
+        outputToConsole.set(true)
+        outputColorName.set("RED")
+        enableExperimentalRules.set(false)
+        disabledRules = ["import-ordering", "max-line-length", "parameter-list-wrapping"]
+        reporters {
+            reporter "checkstyle"
+            reporter "plain"
+        }
+        filter {
+            exclude({ it.file.absolutePath.contains("/generated/") })
+        }
+    }
 }
 
 dependencies {

azure-communication-ui/chat/src/test/java/com/azure/android/communication/ui/chat/locator/ServiceLocatorTest.kt

@@ -0,0 +1,115 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+package com.azure.android.communication.ui.chat.locator
+
+import org.junit.Assert
+import org.junit.Test
+
+// / Tests for the Service Locator Pattern
+class ServiceLocatorTest {
+
+    /*
+        ScaffoldingObjects
+        BasicObjectHello = stores: "hello"
+        BasicObjectWorld = stores: "world"
+        BasicObjectHelloWorld = Combines above objects to output "hello world"
+     */
+    internal inner class BasicObjectHello {
+        val data = "hello"
+    }
+
+    internal inner class BasicObjectWorld : ServiceLocator.Disposable {
+        val data = "world"
+        var disposed = false
+        override fun dispose() {
+            disposed = true
+        }
+    }
+
+    internal inner class BasicObjectHelloWorld(
+        hello: BasicObjectHello?,
+        world: BasicObjectWorld?
+    ) {
+        val data: String
+
+        init {
+            data = hello!!.data + " " + world!!.data
+        }
+    }
+
+    // Test basic, no-dep location
+    @Test
+    fun basicTest() {
+        val locator = ServiceLocator()
+        locator.addTypedBuilder {
+            BasicObjectHello()
+        }
+
+        locator.addTypedBuilder {
+            BasicObjectWorld()
+        }
+
+        val basicObjectHello = locator.locate<BasicObjectHello>()
+        val basicObjectWorld = locator.locate<BasicObjectWorld>()
+
+        Assert.assertEquals(basicObjectHello!!.data, "hello")
+        Assert.assertEquals(basicObjectWorld!!.data, "world")
+    }
+
+    // Test that Dispose is called after clear()
+    @Test
+    fun disposeTest() {
+        val locator = ServiceLocator()
+
+        locator.addTypedBuilder { BasicObjectWorld() }
+        val basicObjectWorld = locator.locate<BasicObjectWorld>()
+        Assert.assertEquals(basicObjectWorld!!.disposed, false)
+        locator.clear()
+        Assert.assertEquals(basicObjectWorld.disposed, true)
+    }
+
+    // Test to see if the HelloWorld object can be built
+    @Test
+    fun dependenciesTest() {
+        val locator = ServiceLocator()
+
+        locator.addTypedBuilder {
+            BasicObjectHello()
+        }
+
+        locator.addTypedBuilder {
+            BasicObjectWorld()
+        }
+
+        locator.addTypedBuilder {
+            BasicObjectHelloWorld(
+                locator.locate(),
+                locator.locate()
+            )
+        }
+
+        val basicObjectHello = locator.locate<BasicObjectHelloWorld>()
+
+        Assert.assertEquals(basicObjectHello!!.data, "hello world")
+    }
+
+    @Test
+    fun failedDependencyTestWithInitializeAll() {
+        val locator = ServiceLocator()
+
+        locator.addTypedBuilder {
+            BasicObjectHello()
+        }
+
+        locator.addTypedBuilder {
+            BasicObjectHelloWorld(
+                locator.locate(),
+                locator.locate()
+            )
+        }
+
+        Assert.assertThrows(java.lang.IllegalArgumentException::class.java,) {
+            locator.initializeAll()
+        }
+    }
+}