[WIP] Allow test classes to provide runtime hints via declarative mec…

…hanisms

Closes spring-projectsgh-29455

spring-test/src/main/java/org/springframework/test/context/aot/TestContextAotGenerator.java

@@ -16,7 +16,10 @@
 
 package org.springframework.test.context.aot;
 
+import java.util.Arrays;
+import java.util.LinkedHashSet;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Stream;
 
@@ -30,12 +33,19 @@
 import org.springframework.aot.generate.GeneratedFiles;
 import org.springframework.aot.generate.GenerationContext;
 import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.RuntimeHintsRegistrar;
 import org.springframework.aot.hint.TypeReference;
+import org.springframework.aot.hint.annotation.ReflectiveRuntimeHintsRegistrar;
+import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.aot.AotServices;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.annotation.ImportRuntimeHints;
 import org.springframework.context.aot.ApplicationContextAotGenerator;
 import org.springframework.context.support.GenericApplicationContext;
+import org.springframework.core.annotation.MergedAnnotation;
+import org.springframework.core.annotation.MergedAnnotations;
+import org.springframework.core.annotation.MergedAnnotations.SearchStrategy;
 import org.springframework.core.log.LogMessage;
 import org.springframework.javapoet.ClassName;
 import org.springframework.test.context.BootstrapUtils;
@@ -117,16 +127,36 @@ public void processAheadOfTime(Stream<Class<?>> testClasses) throws TestContextA
 		try {
 			resetAotFactories();
 
+			Set<RuntimeHintsRegistrar> runtimeHintsRegistrars = new LinkedHashSet<>();
+			ReflectiveRuntimeHintsRegistrar reflectiveRuntimeHintsRegistrar = new ReflectiveRuntimeHintsRegistrar();
+
 			MultiValueMap<MergedContextConfiguration, Class<?>> mergedConfigMappings = new LinkedMultiValueMap<>();
 			ClassLoader classLoader = getClass().getClassLoader();
 			testClasses.forEach(testClass -> {
 				MergedContextConfiguration mergedConfig = buildMergedContextConfiguration(testClass);
 				mergedConfigMappings.add(mergedConfig, testClass);
+
+				MergedAnnotations.from(testClass, SearchStrategy.TYPE_HIERARCHY).stream(ImportRuntimeHints.class)
+						.map(MergedAnnotation::synthesize)
+						.map(ImportRuntimeHints::value)
+						.flatMap(Arrays::stream)
+						.map(BeanUtils::instantiateClass)
+						.forEach(runtimeHintsRegistrars::add);
+
+				reflectiveRuntimeHintsRegistrar.registerRuntimeHints(this.runtimeHints, testClass);
 				this.testRuntimeHintsRegistrars.forEach(registrar ->
 						registrar.registerHints(this.runtimeHints, testClass, classLoader));
 			});
 			MultiValueMap<ClassName, Class<?>> initializerClassMappings = processAheadOfTime(mergedConfigMappings);
 
+			runtimeHintsRegistrars.forEach(registrar -> {
+				if (logger.isTraceEnabled()) {
+					logger.trace("Processing RuntimeHints contribution from test class [%s]"
+							.formatted(registrar.getClass().getCanonicalName()));
+				}
+				registrar.registerHints(this.runtimeHints, classLoader);
+			});
+
 			generateAotTestContextInitializerMappings(initializerClassMappings);
 			generateAotTestAttributeMappings();
 		}

spring-test/src/test/java/org/springframework/test/context/aot/DeclarativeRuntimeHintsTests.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2002-2022 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.springframework.test.context.aot;
+
+import java.util.Set;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.aot.generate.InMemoryGeneratedFiles;
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.test.context.aot.samples.hints.DeclarativeRuntimeHintsSpringJupiterTests;
+
+import static java.util.Comparator.comparing;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.springframework.aot.hint.predicate.RuntimeHintsPredicates.reflection;
+import static org.springframework.aot.hint.predicate.RuntimeHintsPredicates.resource;
+
+/**
+ * Tests for declarative support for registering run-time hints for tests, tested
+ * via the {@link TestContextAotGenerator}
+ *
+ * @author Sam Brannen
+ * @since 6.0
+ */
+class DeclarativeRuntimeHintsTests extends AbstractAotTests {
+
+	@Test
+	void declarativeRuntimeHints() {
+		Set<Class<?>> testClasses = Set.of(DeclarativeRuntimeHintsSpringJupiterTests.class);
+		TestContextAotGenerator generator = new TestContextAotGenerator(new InMemoryGeneratedFiles());
+		RuntimeHints runtimeHints = generator.getRuntimeHints();
+
+		generator.processAheadOfTime(testClasses.stream().sorted(comparing(Class::getName)));
+
+		// @Reflective
+		assertReflectionRegistered(runtimeHints, DeclarativeRuntimeHintsSpringJupiterTests.class);
+
+		// @ImportRuntimeHints
+		assertThat(resource().forResource("org/example/config/enigma.txt")).accepts(runtimeHints);
+		assertThat(resource().forResource("org/example/config/level2/foo.txt")).accepts(runtimeHints);
+	}
+
+	private static void assertReflectionRegistered(RuntimeHints runtimeHints, Class<?> type) {
+		assertThat(reflection().onType(type))
+			.as("Reflection hint for %s", type.getSimpleName())
+			.accepts(runtimeHints);
+	}
+
+	private static void assertReflectionRegistered(RuntimeHints runtimeHints, Class<?> type, MemberCategory memberCategory) {
+		assertThat(reflection().onType(type).withMemberCategory(memberCategory))
+			.as("Reflection hint for %s with category %s", type.getSimpleName(), memberCategory)
+			.accepts(runtimeHints);
+	}
+
+}

spring-test/src/test/java/org/springframework/test/context/aot/samples/hints/DeclarativeRuntimeHintsSpringJupiterTests.java

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2002-2022 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.springframework.test.context.aot.samples.hints;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.aot.hint.RuntimeHints;
+import org.springframework.aot.hint.RuntimeHintsRegistrar;
+import org.springframework.aot.hint.annotation.Reflective;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.ImportRuntimeHints;
+import org.springframework.test.context.aot.samples.hints.DeclarativeRuntimeHintsSpringJupiterTests.DemoHints;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Sam Brannen
+ * @since 6.0
+ */
+@SpringJUnitConfig
+@Reflective
+@ImportRuntimeHints(DemoHints.class)
+public class DeclarativeRuntimeHintsSpringJupiterTests {
+
+	@Test
+	void test(@Autowired String foo) {
+		assertThat(foo).isEqualTo("bar");
+	}
+
+
+	@Configuration(proxyBeanMethods = false)
+	static class Config {
+
+		@Bean
+		String foo() {
+			return "bar";
+		}
+	}
+
+	static class DemoHints implements RuntimeHintsRegistrar {
+
+		@Override
+		public void registerHints(RuntimeHints hints, ClassLoader classLoader) {
+			hints.resources().registerPattern("org/example/config/*.txt");
+		}
+
+	}
+
+}