Find service connections declaring in enclosing classes

Fixes gh-34790

spring-boot-project/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/service/connection/ServiceConnectionContextCustomizer.java

@@ -78,4 +78,8 @@ class ServiceConnectionContextCustomizer implements ContextCustomizer {
 		return new RootBeanDefinition((Class<T>) instance.getClass(), () -> instance);
 	}
 
+	List<ContainerConnectionSource<?, ?, ?>> getSources() {
+		return this.sources;
+	}
+
 }

spring-boot-project/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/service/connection/ServiceConnectionContextCustomizerFactory.java

@@ -28,6 +28,7 @@ import org.springframework.core.annotation.MergedAnnotations;
 import org.springframework.test.context.ContextConfigurationAttributes;
 import org.springframework.test.context.ContextCustomizer;
 import org.springframework.test.context.ContextCustomizerFactory;
+import org.springframework.test.context.TestContextAnnotationUtils;
 import org.springframework.util.Assert;
 import org.springframework.util.ReflectionUtils;
 
@@ -44,12 +45,19 @@ class ServiceConnectionContextCustomizerFactory implements ContextCustomizerFact
 	public ContextCustomizer createContextCustomizer(Class<?> testClass,
 			List<ContextConfigurationAttributes> configAttributes) {
 		List<ContainerConnectionSource<?, ?, ?>> sources = new ArrayList<>();
-		ReflectionUtils.doWithFields(testClass, (field) -> {
+		findSources(testClass, sources);
+		return (sources.isEmpty()) ? null : new ServiceConnectionContextCustomizer(sources);
+	}
+
+	private void findSources(Class<?> clazz, List<ContainerConnectionSource<?, ?, ?>> sources) {
+		ReflectionUtils.doWithFields(clazz, (field) -> {
 			MergedAnnotations annotations = MergedAnnotations.from(field);
 			annotations.stream(ServiceConnection.class)
 				.forEach((annotation) -> sources.add(createSource(field, annotation)));
 		});
-		return (sources.isEmpty()) ? null : new ServiceConnectionContextCustomizer(sources);
+		if (TestContextAnnotationUtils.searchEnclosingClass(clazz)) {
+			findSources(clazz.getEnclosingClass(), sources);
+		}
 	}
 
 	private ContainerConnectionSource<?, ?, ?> createSource(Field field,

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/service/connection/ServiceConnectionContextCustomizerFactoryTests.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2012-2023 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.boot.test.autoconfigure.service.connection;
+
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.testcontainers.containers.GenericContainer;
+
+import org.springframework.boot.autoconfigure.service.connection.ConnectionDetails;
+import org.springframework.boot.test.autoconfigure.service.connection.ServiceConnectionContextCustomizerFactoryTests.ServiceConnections.NestedClass;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link ServiceConnectionContextCustomizerFactory}.
+ *
+ * @author Andy Wilkinson
+ */
+public class ServiceConnectionContextCustomizerFactoryTests {
+
+	private final ServiceConnectionContextCustomizerFactory factory = new ServiceConnectionContextCustomizerFactory();
+
+	@Test
+	void whenClassHasNoServiceConnectionsThenCreateReturnsNull() {
+		assertThat(this.factory.createContextCustomizer(NoServiceConnections.class, null)).isNull();
+	}
+
+	@Test
+	void whenClassHasServiceConnectionsThenCreateReturnsCustomizer() {
+		ServiceConnectionContextCustomizer customizer = (ServiceConnectionContextCustomizer) this.factory
+			.createContextCustomizer(ServiceConnections.class, null);
+		assertThat(customizer).isNotNull();
+		assertThat(customizer.getSources()).hasSize(2);
+	}
+
+	@Test
+	void whenEnclosingClassHasServiceConnectionsThenCreateReturnsCustomizer() {
+		ServiceConnectionContextCustomizer customizer = (ServiceConnectionContextCustomizer) this.factory
+			.createContextCustomizer(NestedClass.class, null);
+		assertThat(customizer).isNotNull();
+		assertThat(customizer.getSources()).hasSize(3);
+	}
+
+	static class NoServiceConnections {
+
+	}
+
+	static class ServiceConnections {
+
+		@ServiceConnection(TestConnectionDetails.class)
+		private static GenericContainer<?> service1 = new GenericContainer<>("example");
+
+		@ServiceConnection(TestConnectionDetails.class)
+		private static GenericContainer<?> service2 = new GenericContainer<>("example");
+
+		@Nested
+		class NestedClass {
+
+			@ServiceConnection(TestConnectionDetails.class)
+			private static GenericContainer<?> service3 = new GenericContainer<>("example");
+
+		}
+
+	}
+
+	static class TestConnectionDetails implements ConnectionDetails {
+
+	}
+
+}