Document how to use DataNeo4jTest with reactive access

Closes gh-23630

Author: snicoll

spring-boot-project/spring-boot-docs/src/docs/asciidoc/spring-boot-features.adoc

@@ -7605,6 +7605,9 @@ If that is not what you want, you can disable transaction management for a test
 	}
 ----
 
+NOTE: Transactional tests are not supported with reactive access.
+If you are using this style, you must configure `@DataNeo4jTest` tests as described above.
+
 
 
 [[boot-features-testing-spring-boot-applications-testing-autoconfigured-redis-test]]

spring-boot-project/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/data/neo4j/DataNeo4jTest.java

@@ -45,7 +45,9 @@
  * configuration relevant to Neo4j tests.
  * <p>
  * By default, tests annotated with {@code @DataNeo4jTest} are transactional with the
- * usual test-related semantics (i.e. rollback by default).
+ * usual test-related semantics (i.e. rollback by default). This feature is not supported
+ * with reactive access so this should be disabled by annotating the test class with
+ * {@code @Transactional(propagation = Propagation.NOT_SUPPORTED)}.
  * <p>
  * When using JUnit 4, this annotation should be used in combination with
  * {@code @RunWith(SpringRunner.class)}.

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/data/neo4j/DataNeo4jTestReactiveIntegrationTests.java

@@ -31,23 +31,25 @@
 import org.springframework.boot.test.context.TestConfiguration;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
-import org.springframework.data.neo4j.core.DatabaseSelectionProvider;
+import org.springframework.data.neo4j.core.ReactiveDatabaseSelectionProvider;
 import org.springframework.data.neo4j.core.ReactiveNeo4jTemplate;
-import org.springframework.data.neo4j.core.transaction.Neo4jTransactionManager;
-import org.springframework.data.neo4j.repository.config.ReactiveNeo4jRepositoryConfigurationExtension;
+import org.springframework.data.neo4j.core.transaction.ReactiveNeo4jTransactionManager;
 import org.springframework.test.context.DynamicPropertyRegistry;
 import org.springframework.test.context.DynamicPropertySource;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Transactional;
 
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
- * Integration tests for the reactive SDN/RX Neo4j test slice.
+ * Integration tests for {@link DataNeo4jTest @DataNeo4jTest} with reactive style.
  *
  * @author Michael J. Simons
  * @author Scott Frederick
  * @since 2.4.0
  */
 @DataNeo4jTest
+@Transactional(propagation = Propagation.NOT_SUPPORTED)
 @Testcontainers(disabledWithoutDocker = true)
 class DataNeo4jTestReactiveIntegrationTests {
 
@@ -82,18 +84,13 @@ void didNotInjectExampleService() {
 				.isThrownBy(() -> this.applicationContext.getBean(ExampleService.class));
 	}
 
-	// Providing this bean fulfills a requirement that a @Transactional test has a
-	// PlatformTransactionManager in the app context (enforced by
-	// org.springframework.test.context.transaction.TransactionalTestExecutionListener).
-	// Providing a ReactiveNeo4jTransactionManager would be more appropriate, but won't
-	// allow the test to succeed.
 	@TestConfiguration(proxyBeanMethods = false)
 	static class ReactiveTransactionManagerConfiguration {
 
-		@Bean(ReactiveNeo4jRepositoryConfigurationExtension.DEFAULT_TRANSACTION_MANAGER_BEAN_NAME)
-		Neo4jTransactionManager reactiveTransactionManager(Driver driver,
-				DatabaseSelectionProvider databaseNameProvider) {
-			return new Neo4jTransactionManager(driver, databaseNameProvider);
+		@Bean
+		ReactiveNeo4jTransactionManager reactiveTransactionManager(Driver driver,
+				ReactiveDatabaseSelectionProvider databaseNameProvider) {
+			return new ReactiveNeo4jTransactionManager(driver, databaseNameProvider);
 		}
 
 	}