Add Maven plugin support for processing test contexts Ahead-of-time

Refactor and update the Spring Boot Maven Plugin so that it can
be used to perform AOT processing of test classes.

Closes gh-32191

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/intTest/java/org/springframework/boot/maven/AotTests.java

@@ -33,7 +33,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Andy Wilkinson
  */
 @ExtendWith(MavenBuildExtension.class)
-public class AotGenerateTests {
+public class AotTests {
 
 	@TestTemplate
 	void whenAotRunsSourcesAreGenerated(MavenBuild mavenBuild) {
@@ -113,6 +113,20 @@ public class AotGenerateTests {
 		});
 	}
 
+	@TestTemplate
+	void whenAotTestRunsSourcesAndResourcesAreGenerated(MavenBuild mavenBuild) {
+		mavenBuild.project("aot-test").goals("test").execute((project) -> {
+			Path aotDirectory = project.toPath().resolve("target/spring-aot/test");
+			assertThat(collectRelativePaths(aotDirectory.resolve("sources"))).contains(Path.of("org", "test",
+					"SampleApplicationTests__TestContext001_ApplicationContextInitializer.java"));
+			Path testClassesDirectory = project.toPath().resolve("target/test-classes");
+			assertThat(collectRelativePaths(testClassesDirectory)).contains(Path.of("META-INF", "native-image",
+					"org.springframework.boot.maven.it", "aot-test", "reflect-config.json"));
+			assertThat(collectRelativePaths(testClassesDirectory)).contains(Path.of("org", "test",
+					"SampleApplicationTests__TestContext001_ApplicationContextInitializer.class"));
+		});
+	}
+
 	Stream<Path> collectRelativePaths(Path sourceDirectory) {
 		try {
 			return Files.walk(sourceDirectory).filter(Files::isRegularFile)

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/intTest/projects/aot-test/pom.xml

@@ -0,0 +1,66 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>org.springframework.boot.maven.it</groupId>
+	<artifactId>aot-test</artifactId>
+	<version>0.0.1.BUILD-SNAPSHOT</version>
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<maven.compiler.source>@java.version@</maven.compiler.source>
+		<maven.compiler.target>@java.version@</maven.compiler.target>
+	</properties>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>@project.groupId@</groupId>
+				<artifactId>@project.artifactId@</artifactId>
+				<version>@project.version@</version>
+				<executions>
+					<execution>
+						<goals>
+							<goal>process-test-aot</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot</artifactId>
+			<version>@project.version@</version>
+		</dependency>
+		<dependency>
+			<groupId>jakarta.servlet</groupId>
+			<artifactId>jakarta.servlet-api</artifactId>
+			<version>@jakarta-servlet.version@</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-test</artifactId>
+			<version>@spring-framework.version@</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-test</artifactId>
+			<version>@project.version@</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.assertj</groupId>
+			<artifactId>assertj-core</artifactId>
+			<version>@assertj.version@</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.junit.jupiter</groupId>
+			<artifactId>junit-jupiter</artifactId>
+			<version>@junit-jupiter.version@</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+</project>

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/intTest/projects/aot-test/src/main/java/org/test/SampleApplication.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2012-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.test;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration(proxyBeanMethods = false)
+public class SampleApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(SampleApplication.class, args);
+	}
+
+}

spring-boot-project/spring-boot-tools/spring-boot-maven-plugin/src/intTest/projects/aot-test/src/test/java/org/test/SampleApplicationTests.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2012-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ package org.test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
+
+@SpringJUnitConfig
+class SampleApplicationTests {
+
+	@Autowired
+	private MyBean myBean;
+
+	@Test
+	void contextLoads() {
+		assertThat(this.myBean).isNotNull();
+	}
+
+	@Configuration
+	static class MyConfig {
+
+		@Bean
+		MyBean myBean() {
+			return new MyBean();
+		}
+
+	}
+
+	static class MyBean {
+
+	}
+
+}