Polish "Prevent double registration of event publisher registrar"

See gh-39297

Author: wilkinsona

spring-boot-project/spring-boot-testcontainers/src/main/java/org/springframework/boot/testcontainers/properties/TestcontainersPropertySource.java

@@ -138,7 +138,7 @@ static TestcontainersPropertySource getOrAdd(ConfigurableEnvironment environment
 	 * to the {@link TestcontainersPropertySource}. This class is a
 	 * {@link BeanFactoryPostProcessor} so that it is initialized as early as possible.
 	 */
-	private static class EventPublisherRegistrar implements BeanFactoryPostProcessor, ApplicationEventPublisherAware {
+	static class EventPublisherRegistrar implements BeanFactoryPostProcessor, ApplicationEventPublisherAware {
 
 		static final String NAME = EventPublisherRegistrar.class.getName();
 

spring-boot-project/spring-boot-testcontainers/src/test/java/org/springframework/boot/testcontainers/properties/TestcontainersPropertySourceTests.java

@@ -23,6 +23,8 @@
 import org.junit.jupiter.api.Test;
 
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.boot.testcontainers.properties.TestcontainersPropertySource.EventPublisherRegistrar;
 import org.springframework.context.ApplicationEvent;
 import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.core.env.EnumerablePropertySource;
@@ -42,6 +44,13 @@ class TestcontainersPropertySourceTests {
 
 	private MockEnvironment environment = new MockEnvironment();
 
+	private GenericApplicationContext context = new GenericApplicationContext();
+
+	TestcontainersPropertySourceTests() {
+		((DefaultListableBeanFactory) this.context.getBeanFactory()).setAllowBeanDefinitionOverriding(false);
+		this.context.setEnvironment(this.environment);
+	}
+
 	@Test
 	void getPropertyWhenHasValueSupplierReturnsSuppliedValue() {
 		DynamicPropertyRegistry registry = TestcontainersPropertySource.attach(this.environment);
@@ -90,14 +99,14 @@ void getSourceReturnsImmutableSource() {
 	}
 
 	@Test
-	void attachWhenNotAttachedAttaches() {
+	void attachToEnvironmentWhenNotAttachedAttaches() {
 		TestcontainersPropertySource.attach(this.environment);
 		PropertySource<?> propertySource = this.environment.getPropertySources().get(TestcontainersPropertySource.NAME);
 		assertThat(propertySource).isNotNull();
 	}
 
 	@Test
-	void attachWhenAlreadyAttachedReturnsExisting() {
+	void attachToEnvironmentWhenAlreadyAttachedReturnsExisting() {
 		DynamicPropertyRegistry r1 = TestcontainersPropertySource.attach(this.environment);
 		PropertySource<?> p1 = this.environment.getPropertySources().get(TestcontainersPropertySource.NAME);
 		DynamicPropertyRegistry r2 = TestcontainersPropertySource.attach(this.environment);
@@ -106,6 +115,24 @@ void attachWhenAlreadyAttachedReturnsExisting() {
 		assertThat(p1).isSameAs(p2);
 	}
 
+	@Test
+	void attachToEnvironmentAndContextWhenNotAttachedAttaches() {
+		TestcontainersPropertySource.attach(this.environment, this.context);
+		PropertySource<?> propertySource = this.environment.getPropertySources().get(TestcontainersPropertySource.NAME);
+		assertThat(propertySource).isNotNull();
+		assertThat(this.context.containsBean(EventPublisherRegistrar.NAME));
+	}
+
+	@Test
+	void attachToEnvironmentAndContextWhenAlreadyAttachedReturnsExisting() {
+		DynamicPropertyRegistry r1 = TestcontainersPropertySource.attach(this.environment, this.context);
+		PropertySource<?> p1 = this.environment.getPropertySources().get(TestcontainersPropertySource.NAME);
+		DynamicPropertyRegistry r2 = TestcontainersPropertySource.attach(this.environment, this.context);
+		PropertySource<?> p2 = this.environment.getPropertySources().get(TestcontainersPropertySource.NAME);
+		assertThat(r1).isSameAs(r2);
+		assertThat(p1).isSameAs(p2);
+	}
+
 	@Test
 	void getPropertyPublishesEvent() {
 		try (GenericApplicationContext applicationContext = new GenericApplicationContext()) {