SpringBoot Document that @DataNeo4jTest does not support transactional tests with a reactive setup

The former SDN rx provides a @ReactiveDataNeo4jTest for reactive applications.

I am try to use @DataNeo4jTest(it declared working with Servlet stack and reactive stack) in the new sample, it failed.

Check the test examples: PostRepositoryTest.java

When running this test, I got a transaction exception.

java.lang.IllegalStateException: Failed to retrieve PlatformTransactionManager for @Transactional test: [DefaultTestContext@4bd31064 testClass = PostRepositoryWithTestContainersTest, testInstance = com.example.demo.PostRepositoryWithTestContainersTest@1440c311, testMethod = testAllPosts@PostRepositoryWithTestContainersTest, testException = [null], mergedContextConfiguration = [MergedContextConfiguration@e3c0e40 testClass = PostRepositoryWithTestContainersTest, locations = '{}', classes = '{class com.example.demo.DemoApplication}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{org.springframework.boot.test.autoconfigure.data.neo4j.DataNeo4jTestContextBootstrapper=true}', contextCustomizers = set[[ImportsContextCustomizer@329dbdbf key = [org.springframework.boot.autoconfigure.cache.CacheAutoConfiguration, org.springframework.boot.autoconfigure.neo4j.Neo4jAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.transaction.TransactionAutoConfiguration]], org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@121314f7, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@576d5deb, org.springframework.boot.test.mock.mockito.MockitoContextCustomizer@0, org.springframework.boot.test.autoconfigure.OverrideAutoConfigurationContextCustomizerFactory$DisableAutoConfigurationContextCustomizer@1ffaf86, org.springframework.boot.test.autoconfigure.actuate.metrics.MetricsExportContextCustomizerFactory$DisableMetricExportContextCustomizer@20140db9, org.springframework.boot.test.autoconfigure.filter.TypeExcludeFiltersContextCustomizer@351584c0, org.springframework.boot.test.autoconfigure.properties.PropertyMappingContextCustomizer@b783eabf, org.springframework.boot.test.autoconfigure.web.servlet.WebDriverContextCustomizerFactory$Customizer@3b0fe47a, org.springframework.test.context.support.DynamicPropertiesContextCustomizer@29894581, org.springframework.boot.test.context.SpringBootTestArgs@1], contextLoader = 'org.springframework.boot.test.context.SpringBootContextLoader', parent = [null]], attributes = map[[empty]]]
    at org.springframework.util.Assert.state(Assert.java:97) ~[spring-core-5.3.0-RC1.jar:5.3.0-RC1]
    at org.springframework.test.context.transaction.TransactionalTestExecutionListener.beforeTestMethod(TransactionalTestExecutionListener.java:199) ~[spring-test-5.3.0-RC1.jar:5.3.0-RC1]
    at org.springframework.test.context.TestContextManager.beforeTestMethod(TestContextManager.java:289) ~[spring-test-5.3.0-RC1.jar:5.3.0-RC1]
    at org.springframework.test.context.junit.jupiter.SpringExtension.beforeEach(SpringExtension.java:109) ~[spring-test-5.3.0-RC1.jar:5.3.0-RC1]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeBeforeEachCallbacks$1(TestMethodTestDescriptor.java:159) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeBeforeMethodsOrCallbacksUntilExceptionOccurs$5(TestMethodTestDescriptor.java:195) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeBeforeMethodsOrCallbacksUntilExceptionOccurs(TestMethodTestDescriptor.java:195) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeBeforeEachCallbacks(TestMethodTestDescriptor.java:158) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:125) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:65) ~[junit-jupiter-engine-5.7.0.jar:5.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51) ~[junit-platform-engine-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75) ~[junit-platform-launcher-1.7.0.jar:1.7.0]
    at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71) ~[junit5-rt.jar:na]
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33) ~[junit-rt.jar:na]
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:220) ~[junit-rt.jar:na]
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:53) ~[junit-rt.jar:na]



java.lang.IllegalStateException: Failed to retrieve PlatformTransactionManager for @Transactional test: [DefaultTestContext@4bd31064 testClass = PostRepositoryWithTestContainersTest, testInstance = com.example.demo.PostRepositoryWithTestContainersTest@1440c311, testMethod = testAllPosts@PostRepositoryWithTestContainersTest, testException = [null], mergedContextConfiguration = [MergedContextConfiguration@e3c0e40 testClass = PostRepositoryWithTestContainersTest, locations = '{}', classes = '{class com.example.demo.DemoApplication}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{org.springframework.boot.test.autoconfigure.data.neo4j.DataNeo4jTestContextBootstrapper=true}', contextCustomizers = set[[ImportsContextCustomizer@329dbdbf key = [org.springframework.boot.autoconfigure.cache.CacheAutoConfiguration, org.springframework.boot.autoconfigure.neo4j.Neo4jAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveDataAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jReactiveRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.data.neo4j.Neo4jRepositoriesAutoConfiguration, org.springframework.boot.autoconfigure.transaction.TransactionAutoConfiguration]], org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@121314f7, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@576d5deb, org.springframework.boot.test.mock.mockito.MockitoContextCustomizer@0, org.springframework.boot.test.autoconfigure.OverrideAutoConfigurationContextCustomizerFactory$DisableAutoConfigurationContextCustomizer@1ffaf86, org.springframework.boot.test.autoconfigure.actuate.metrics.MetricsExportContextCustomizerFactory$DisableMetricExportContextCustomizer@20140db9, org.springframework.boot.test.autoconfigure.filter.TypeExcludeFiltersContextCustomizer@351584c0, org.springframework.boot.test.autoconfigure.properties.PropertyMappingContextCustomizer@b783eabf, org.springframework.boot.test.autoconfigure.web.servlet.WebDriverContextCustomizerFactory$Customizer@3b0fe47a, org.springframework.test.context.support.DynamicPropertiesContextCustomizer@29894581, org.springframework.boot.test.context.SpringBootTestArgs@1], contextLoader = 'org.springframework.boot.test.context.SpringBootContextLoader', parent = [null]], attributes = map[[empty]]]

    at org.springframework.util.Assert.state(Assert.java:97)
    at org.springframework.test.context.transaction.TransactionalTestExecutionListener.beforeTestMethod(TransactionalTestExecutionListener.java:199)
    at org.springframework.test.context.TestContextManager.beforeTestMethod(TestContextManager.java:289)
    at org.springframework.test.context.junit.jupiter.SpringExtension.beforeEach(SpringExtension.java:109)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeBeforeEachCallbacks$1(TestMethodTestDescriptor.java:159)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeBeforeMethodsOrCallbacksUntilExceptionOccurs$5(TestMethodTestDescriptor.java:195)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeBeforeMethodsOrCallbacksUntilExceptionOccurs(TestMethodTestDescriptor.java:195)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeBeforeEachCallbacks(TestMethodTestDescriptor.java:158)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:125)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:65)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:143)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:129)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:127)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:126)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:84)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:108)
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88)
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54)
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67)
    at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:96)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:75)
    at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:220)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:53)

Comment From: snicoll

in the new sample, it failed.

That test never worked the way you expect. The Test context framework does not have support for @Test rollback semantic and a reactive transaction manager. See https://github.com/spring-projects/spring-framework/issues/24226

I am try to use @DataNeo4jTest(it declared working with Servlet stack and reactive stack) in

Where have you seen that?

Comment From: hantsy

The newest @DataNeo4jTest ported all features from SDN Rx? there is a testing autoconfiguration.

See here

@DataNeo4jTest provides both imperative and reactive infrastructure by default.

Comment From: hantsy

In the orignal SDN rx, there is another @ReactiveDataNeo4jTest for a reactive app.

Comment From: snicoll

See here

That's not in the Spring Boot codebase so you shouldn't rely on that. I am aware of what SDN Rx did and I think I've already mentioned that we've decided to go another route.

Please read my comment again. I mentioned that this test never worked the way you expect. @ReactiveDataNeo4jTest never worked as intended either since the @Test context framework doesn't support that feature at all.

Let's document the limitation in the meantime.

Comment From: snicoll

Removing @Transactional from @DataNeo4jTest would be another option but that would be a breaking change.

Comment From: hantsy

Is there any workaround to make my testing codes working again?

Comment From: hantsy

@snicoll Return to use @SpringBootTest to make it work.

Comment From: snicoll

We've decided to remove @Transactional from @DataNeo4jTest to support a reactive setup. This would be a breaking change for users relying on transactional-based test that can hopefully get the previous behaviour by adding @Transactional on such test.

Comment From: sbrannen

Another option would be to keep it @Transactional and add a note in the Javadoc that the user can annotate a given test class with @Transactional(propagation = NOT_SUPPORTED) to disable transactional test support. See the "Enabling and Disabling Transactions" section of the Javadoc for details.

Comment From: hantsy

@sbrannen I was confused that why transational became a must in this version?

Comment From: wilkinsona

@sbrannen AIUI, that won't work as there will be no PlatformTransactionManager bean in the context yet the presence of @Transactional at the class level will cause the test framework to require such a bean.

Comment From: sbrannen

@wilkinsona, I don't think that's the case.

https://github.com/spring-projects/spring-framework/blob/cd835b3124df094c3c4730270e9cb835738a315d/spring-test/src/main/java/org/springframework/test/context/transaction/TransactionalTestExecutionListener.java#L216-L222

In the code above, if the propagation is set to PROPAGATION_NOT_SUPPORTED, the lookup for the TransactionManager will be skipped.

I'll see if I can throw together a simple test case that demonstrates this.

Comment From: sbrannen

The following test passes.

package example;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import org.junit.jupiter.api.Test;

import org.springframework.context.annotation.Configuration;
import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.transaction.support.TransactionSynchronizationManager;

import static org.assertj.core.api.Assertions.assertThat;
import static org.springframework.transaction.annotation.Propagation.NOT_SUPPORTED;

@SpringJUnitConfig
@TransactionalSliceTest
@Transactional(propagation = NOT_SUPPORTED)
class NonTransactionalTests {

    @Test
    void nonTransactional() {
        assertThat(TransactionSynchronizationManager.isActualTransactionActive()).isFalse();
    }

    @Configuration
    static class Config {
        // no PlatformTransactionManager bean present
    }
}

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Transactional
@interface TransactionalSliceTest {
}

If you comment out the @Transactional(propagation = NOT_SUPPORTED) declaration, it will fail with the following.

java.lang.IllegalStateException: Failed to retrieve PlatformTransactionManager for @Transactional test: [DefaultTestContext@10b892d5 testClass = NonTransactionalTests, testInstance = example.NonTransactionalTests@3d3f761a, testMethod = nonTransactional@NonTransactionalTests, testException = [null], mergedContextConfiguration = [MergedContextConfiguration@3546d80f testClass = NonTransactionalTests, locations = '{}', classes = '{class example.NonTransactionalTests$Config}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', contextCustomizers = set[[empty]], contextLoader = 'org.springframework.test.context.support.DelegatingSmartContextLoader', parent = [null]], attributes = map[[empty]]]
    at org.springframework.util.Assert.state(Assert.java:97)
    at org.springframework.test.context.transaction.TransactionalTestExecutionListener.beforeTestMethod(TransactionalTestExecutionListener.java:221)
...

Comment From: wilkinsona

Thanks, @sbrannen. I tried with NEVER and it failed. I should have looked at the code.

Does never need to be treated differently to not supported? If there's no transaction manager then, presumably, there's never going to be a transaction so you don't need one to enforce never's fail-if-there-is-a-transaction semantics.

Comment From: sbrannen

Thanks, @sbrannen. I tried with NEVER and it failed.

I can understand why you'd think NEVER would work the same. Unfortunately that's currently not the case.

See the Javadoc and reference manual for details.

Does never need to be treated differently to not supported? If there's no transaction manager then, presumably, there's never going to be a transaction so you don't need one to enforce never's fail-if-there-is-a-transaction semantics.

Good point. I think it would be safe to support NEVER the same as NOT_SUPPORTED.

TBH, that check was added as a workaround for the removal of the old @NotTransactional annotation from the Spring Framework 2.0 days, and I just didn't see a need to provide two ways to achieve the same thing.

But it certainly won't hurt to make that change. I'll get that done in time for Spring Framework 5.3 GA (see https://github.com/spring-projects/spring-framework/issues/25909).

Comment From: snicoll

In case of @DataNeo4jTest, adding @Transactional(propagation = Propagation.NOT_SUPPORTED) does indeed prevent the TCF to check for a PlatformTransactionManager but it fails further down the road as ReactiveCrudRepository#save requires a ReactiveTransactionManager and we haven't auto-configured one:

Suppressed: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'reactiveTransactionManager' available: No matching TransactionManager bean found for qualifier 'reactiveTransactionManager' - neither qualifier match nor bean name match!
        at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.qualifiedBeanOfType(BeanFactoryAnnotationUtils.java:136)
        at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.qualifiedBeanOfType(BeanFactoryAnnotationUtils.java:95)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.determineQualifiedTransactionManager(TransactionAspectSupport.java:494)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.determineTransactionManager(TransactionAspectSupport.java:475)
        at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:336)
        at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:118)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
        at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
        at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
        at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215)
        at org.springframework.boot.test.autoconfigure.data.neo4j.$Proxy91.save(Unknown Source)
        at reactor.core.publisher.FluxFlatMap.trySubscribeScalarMap(FluxFlatMap.java:151)
        ... 72 more

The fact this test passes with a non reactive transaction manager puzzles me quite a lot. We'll have to investigate a bit more.

Comment From: snicoll

We've changed our mind again based on @sbrannen's feedback and the fact we prefer an extra setup for the minority rather than breaking the mainstream use case. We will have to revisit this arrangement sooner than later which may lead us to remove @Transactional anyway but we think it's too late in 2.4.x to do it.