docs: Update README.md (#16)

README.md

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-# junit5-robolectric-extension
+# Junit5 Robolectric Extension (Experimental)
+
+This is an experimental project that aims to bridge the gap between JUnit 5 and Robolectric, providing a way to run your
+Android unit tests using the modern JUnit 5 framework while leveraging Robolectric's
+in-memory environment.
+
+## Key features
+
+* **JUnit 5 Compatibility:** Run your tests with the latest JUnit 5 features and syntax.
+
+## Current Limitations
+
+* **Parallel Execution:** Parallel test execution is not yet supported. We're actively working on addressing this
+  limitation in future releases.
+* **ClassLoader:** Robolectric's classloader is set before launching the tests. Every test in the suite will use the
+  Robolectric's classloader, even if it is not annotated with the `RobolectricExtension`.
+* **Experimental Status:** This extension is still under development, and its API might change in future versions.
+
+## Installation
+
+1. Add the Maven Central repository to your project's `build.gradle`:
+
+<details open>
+<summary>Kotlin</summary>
+
+```kotlin
+repositories {
+    mavenCentral()
+}
+```
+
+</details>
+
+<details>
+<summary>Groovy</summary>
+
+```groovy
+repositories {
+    mavenCentral()
+}
+```
+
+</details>
+
+2. Enable JUnit Platform Launcher Interceptors and add the dependency to your app or library module's `build.gradle`:
+
+<details open>
+<summary>Kotlin</summary>
+
+```kotlin
+android {
+    testOptions {
+        unitTests {
+            isIncludeAndroidResources = true
+            all { test ->
+                test.useJUnitPlatform()
+                test.jvmArgs(listOf("-Djunit.platform.launcher.interceptors.enabled=true"))
+            }
+        }
+    }
+}
+
+dependencies {
+    testImplementation("tech.apter.junit.jupiter:robolectric-extension:0.1.0")
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:<latest.release>") // JUnit 5 Jupiter Engine
+    // Optional dependencies if you want to use different version than used by the extension
+    testImplementation("org.junit.jupiter:junit-jupiter-api:<latest.release>") // Latest JUnit 5 Jupiter API
+    testImplementation("org.robolectric:robolectric:<latest.release>") // Latest Robolectric version
+}
+```
+
+</details>
+
+<details>
+<summary>Groovy</summary>
+
+```groovy
+android {
+    testOptions {
+        unitTests {
+            includeAndroidResources = true
+            all {
+                useJUnitPlatform()
+                jvmArgs('-Djunit.platform.launcher.interceptors.enabled=true')
+            }
+        }
+    }
+}
+
+dependencies {
+    testImplementation 'tech.apter.junit.jupiter:robolectric-extension:0.1.0'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:<latest.release>' // Latest JUnit 5 Jupiter Engine
+    // Optional dependencies if you want to use different versions than used by the extension
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:<latest.release>' // Latest JUnit 5 Jupiter API
+    testImplementation 'org.robolectric:robolectric:<latest.release>' // Latest Robolectric version
+}
+```
+
+</details>
+
+## Basic usage
+
+1. Annotate your test class with `@ExtendWith`. This extension will manage the Robolectric
+   environment for your tests:
+
+<details open>
+<summary>Kotlin</summary>
+
+```kotlin
+@ExtendWith(RobolectricExtension::class)
+```
+
+</details>
+
+<details>
+<summary>Java</summary>
+
+```java
+@ExtendWith(RobolectricExtension.class)
+```
+
+</details>
+
+2. Utilize the standard JUnit 5 annotations (`@Test`, `@BeforeEach`, `@AfterEach`, etc.) within your test methods. You
+   could also use `org.jetbrains.kotlin:kotlin-test-junit5` package if you want to.
+
+<details open>
+<summary>Kotlin</summary>
+
+```kotlin
+
+import android.app.Application
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import org.junit.jupiter.api.AfterAll
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Assertions.assertInstanceOf
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.BeforeAll
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+import org.robolectric.annotation.Config
+import tech.apter.junit.jupiter.robolectric.RobolectricExtension
+
+@ExtendWith(RobolectricExtension::class)
+@Config(application = RobolectricExtensionSelfTest.MyTestApplication::class)
+class RobolectricExtensionSelfTest {
+
+    @BeforeEach
+    fun setUp() {
+    }
+
+    @AfterEach
+    fun tearDown() {
+    }
+
+    @Test
+    fun shouldInitializeAndBindApplicationAndCallOnCreate() {
+        val application = ApplicationProvider.getApplicationContext<Context>()
+        assertInstanceOf(MyTestApplication::class.java, application)
+        assertTrue((application as MyTestApplication).onCreateWasCalled)
+    }
+
+    companion object {
+        @BeforeAll
+        @JvmStatic
+        fun setUpClass() {
+        }
+
+        @AfterAll
+        @JvmStatic
+        fun tearDownClass() {
+        }
+    }
+
+    class MyTestApplication : Application() {
+        internal var onCreateWasCalled = false
+
+        override fun onCreate() {
+            this.onCreateWasCalled = true
+        }
+    }
+}
+
+```
+
+</details>
+
+<details open>
+<summary>Java</summary>
+
+```java
+
+import android.app.Application;
+import androidx.test.core.app.ApplicationProvider;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Assertions.assertInstanceOf;
+import org.junit.jupiter.api.Assertions.assertTrue;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.robolectric.annotation.Config;
+import tech.apter.junit.jupiter.robolectric.RobolectricExtension;
+
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@ExtendWith(RobolectricExtension.class)
+@Config(application = RobolectricExtensionSelfTest.MyTestApplication::class)
+public class RobolectricExtensionSelfTest {
+
+    @BeforeEach
+    public void setUp() {
+    }
+
+    @AfterEach
+    public void tearDown() {
+    }
+
+    @Test
+    public void shouldInitializeAndBindApplicationAndCallOnCreate() {
+        final Application application = ApplicationProvider.getApplicationContext();
+        assertInstanceOf(MyTestApplication.class, application);
+        assertTrue(((MyTestApplication) application).onCreateWasCalled);
+    }
+
+    @BeforeAll
+    public static void setUpClass() {
+    }
+
+    @AfterAll
+    public static void tearDownClass() {
+    }
+
+    static class MyTestApplication extends Application {
+        public boolean onCreateWasCalled = false;
+
+        @Override
+        public void onCreate() {
+            this.onCreateWasCalled = true;
+        }
+    }
+}
+
+```
+
+</details>
+
+## Important Notes
+
+* Ensure `isIncludeAndroidResources` is set to true in your testOptions configuration to access Android resources for
+  your
+* JUnit Platform Launcher Interceptors must be enabled (`junit.platform.launcher.interceptors.enabled=true`), otherwise
+  test instances will not be created by Robolectric's classloader.
+* Parallel execution is currently not supported. Run tests sequentially for now.
+