Reuse real bean definitions for test bean overrides

But create new bean definition for nonexistent bean definitions based
on BeanOverrideFactoryBean.

See spring-projectsgh-32933

spring-test/src/main/java/org/springframework/test/context/bean/override/BeanOverrideBeanFactoryPostProcessor.java

@@ -57,6 +57,7 @@
  *
  * @author Simon Baslé
  * @author Stephane Nicoll
+ * @author Sam Brannen
  * @since 6.2
  */
 class BeanOverrideBeanFactoryPostProcessor implements BeanFactoryPostProcessor, Ordered {
@@ -155,21 +156,41 @@ else if (enforceExistingDefinition) {
 			beanNameIncludingFactory = beanName;
 		}
 
-		if (existingBeanDefinition != null) {
-			copyBeanDefinitionDetails(existingBeanDefinition, beanDefinition);
-			registry.removeBeanDefinition(beanName);
+		if (existingBeanDefinition instanceof RootBeanDefinition rbd) {
+			rbd.setQualifiedElement(overrideMetadata.getField());
+		}
+
+		// BeanOverrideFactoryBean registered during AOT processing?
+		boolean beanOverrideFactoryBeanRegistered = ((existingBeanDefinition != null) &&
+				BeanOverrideFactoryBean.class.getName().equals(existingBeanDefinition.getBeanClassName()));
+
+		// Need to register a BeanDefinition for a nonexistent bean?
+		if (!beanOverrideFactoryBeanRegistered && (existingBeanDefinition == null)) {
+			convertToBeanOverrideFactoryBeanDefinition(beanDefinition, beanName, overrideMetadata);
+
+			beanOverrideFactoryBeanRegistered = true;
+			registry.registerBeanDefinition(beanName, beanDefinition);
 		}
-		registry.registerBeanDefinition(beanName, beanDefinition);
 
 		Object override = overrideMetadata.createOverride(beanName, existingBeanDefinition, null);
-		if (beanFactory.isSingleton(beanNameIncludingFactory)) {
+		boolean isFactoryBean = beanFactory.isFactoryBean(beanName);
+		if (!beanOverrideFactoryBeanRegistered &&
+				(beanFactory.isSingleton(beanNameIncludingFactory) || isFactoryBean)) {
+
+			// Need to remove singleton registration of FactoryBean?
+			if (isFactoryBean && existingBeanDefinition != null) {
+				registry.removeBeanDefinition(beanName);
+				registry.registerBeanDefinition(beanName, existingBeanDefinition);
+			}
+
 			// Now we have an instance (the override) that we can register.
 			// At this stage we don't expect a singleton instance to be present,
 			// and this call will throw if there is such an instance already.
 			beanFactory.registerSingleton(beanName, override);
 		}
 
 		overrideMetadata.track(override, beanFactory);
+		this.overrideRegistrar.registerBeanInstance(beanName, override);
 		this.overrideRegistrar.registerNameForMetadata(overrideMetadata, beanNameIncludingFactory);
 	}
 
@@ -270,6 +291,17 @@ private Set<String> getExistingBeanNamesByType(ConfigurableListableBeanFactory b
 	}
 
 
+	private static void convertToBeanOverrideFactoryBeanDefinition(RootBeanDefinition beanDefinition, String beanName,
+			OverrideMetadata overrideMetadata) {
+
+		beanDefinition.setBeanClass(BeanOverrideFactoryBean.class);
+		beanDefinition.setTargetType(ResolvableType.forClassWithGenerics(BeanOverrideFactoryBean.class, overrideMetadata.getBeanType()));
+		beanDefinition.setAttribute(FactoryBean.OBJECT_TYPE_ATTRIBUTE, overrideMetadata.getBeanType());
+		beanDefinition.getConstructorArgumentValues().addIndexedArgumentValue(0, beanName);
+		beanDefinition.getConstructorArgumentValues().addIndexedArgumentValue(1, overrideMetadata.getBeanType().resolve());
+	}
+
+
 	static class WrapEarlyBeanPostProcessor implements SmartInstantiationAwareBeanPostProcessor,
 			PriorityOrdered {
 

spring-test/src/main/java/org/springframework/test/context/bean/override/BeanOverrideContextCustomizer.java

@@ -20,6 +20,7 @@
 import java.util.function.Consumer;
 
 import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.config.ConstructorArgumentValues;
 import org.springframework.beans.factory.config.RuntimeBeanReference;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
@@ -35,6 +36,7 @@
  *
  * @author Simon Baslé
  * @author Stephane Nicoll
+ * @author Sam Brannen
  * @since 6.2
  */
 class BeanOverrideContextCustomizer implements ContextCustomizer {
@@ -62,6 +64,11 @@ public void customizeContext(ConfigurableApplicationContext context, MergedConte
 					"that doesn't implement BeanDefinitionRegistry: " + context.getClass());
 		}
 		registerInfrastructure(registry);
+
+		ConfigurableListableBeanFactory beanFactory = context.getBeanFactory();
+		BeanOverrideRegistrar beanOverrideRegistrar = beanFactory.getBean(REGISTRAR_BEAN_NAME, BeanOverrideRegistrar.class);
+		beanFactory.registerSingleton(INFRASTRUCTURE_BEAN_NAME,
+				new BeanOverrideBeanFactoryPostProcessor(this.metadata, beanOverrideRegistrar));
 	}
 
 	Set<OverrideMetadata> getMetadata() {
@@ -75,11 +82,6 @@ private void registerInfrastructure(BeanDefinitionRegistry registry) {
 		RuntimeBeanReference registrarReference = new RuntimeBeanReference(REGISTRAR_BEAN_NAME);
 		addInfrastructureBeanDefinition(registry, WrapEarlyBeanPostProcessor.class, EARLY_INFRASTRUCTURE_BEAN_NAME,
 				constructorArgs -> constructorArgs.addIndexedArgumentValue(0, registrarReference));
-		addInfrastructureBeanDefinition(registry, BeanOverrideBeanFactoryPostProcessor.class, INFRASTRUCTURE_BEAN_NAME,
-				constructorArgs -> {
-					constructorArgs.addIndexedArgumentValue(0, this.metadata);
-					constructorArgs.addIndexedArgumentValue(1, registrarReference);
-				});
 	}
 
 	private void addInfrastructureBeanDefinition(BeanDefinitionRegistry registry,

spring-test/src/main/java/org/springframework/test/context/bean/override/BeanOverrideFactoryBean.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright 2002-2024 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.bean.override;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
+import org.springframework.beans.factory.FactoryBean;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+
+/**
+ * {@link FactoryBean} that retrieves a bean override instance from the
+ * {@link BeanOverrideRegistrar} registered in the {@link BeanFactory}.
+ *
+ * @author Sam Brannen
+ * @since 6.2
+ * @param <T> the type of bean override instance returned from this factory
+ */
+@SuppressWarnings("rawtypes")
+class BeanOverrideFactoryBean<T> implements FactoryBean<T>, BeanFactoryAware {
+
+	private final String beanName;
+
+	private final Class<T> beanType;
+
+	@Nullable
+	private BeanOverrideRegistrar beanOverrideRegistrar;
+
+
+	/**
+	 * Create a new {@code BeanOverrideFactoryBean} for the given bean override
+	 * name and type.
+	 * @param beanName the name of the bean override instance
+	 * @param beanType the type of the bean override instance
+	 */
+	BeanOverrideFactoryBean(String beanName, Class<T> beanType) {
+		this.beanName = beanName;
+		this.beanType = beanType;
+	}
+
+
+	@Override
+	public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+		this.beanOverrideRegistrar = beanFactory.getBean(BeanOverrideRegistrar.class);
+	}
+
+	@Override
+	public Class<T> getObjectType() {
+		return this.beanType;
+	}
+
+	@Override
+	public T getObject() throws Exception {
+		Assert.notNull(this.beanOverrideRegistrar, "BeanOverrideRegistrar must be available");
+		return this.beanOverrideRegistrar.getBeanInstance(this.beanName, this.beanType);
+	}
+
+}

spring-test/src/main/java/org/springframework/test/context/bean/override/BeanOverrideRegistrar.java

@@ -36,12 +36,15 @@
  * for test execution listeners.
  *
  * @author Simon Baslé
+ * @author Sam Brannen
  * @since 6.2
  */
 class BeanOverrideRegistrar implements BeanFactoryAware {
 
 	private final Map<OverrideMetadata, String> beanNameRegistry = new HashMap<>();
 
+	private final Map<String, Object> beanInstanceRegistry = new HashMap<>();
+
 	private final Map<String, OverrideMetadata> earlyOverrideMetadata = new HashMap<>();
 
 	@Nullable
@@ -80,6 +83,32 @@ void registerNameForMetadata(OverrideMetadata metadata, String beanName) {
 		this.beanNameRegistry.put(metadata, beanName);
 	}
 
+	/**
+	 * Register the provided bean override instance under the supplied {@code beanName}.
+	 * @see #getBeanInstance(String, Class)
+	 */
+	void registerBeanInstance(String beanName, Object instance) {
+		this.beanInstanceRegistry.put(beanName, instance);
+	}
+
+	/**
+	 * Get the bean override instance registered under the supplied {@code beanName}.
+	 * @param beanName the name of the bean override instance
+	 * @param requiredType the required type of the bean override instance
+	 * @return the corresponding bean override instance
+	 * @throws IllegalArgumentException if no bean override instance has been
+	 * registered under the supplied name
+	 * @throws ClassCastException if the bean override instance is not of the
+	 * required type
+	 * @see #registerBeanInstance(String, Object)
+	 */
+	<T> T getBeanInstance(String beanName, Class<T> requiredType) {
+		Assert.isTrue(this.beanInstanceRegistry.containsKey(beanName),
+				() -> "Bean instance registry does not contain an entry for bean with name '%s'"
+					.formatted(beanName));
+		return requiredType.cast(this.beanInstanceRegistry.get(beanName));
+	}
+
 	/**
 	 * Mark the provided {@link OverrideMetadata} and {@code beanName} as "wrap
 	 * early", allowing for later bean override using {@link #wrapIfNecessary(Object, String)}.

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

@@ -24,7 +24,6 @@
 import java.util.Set;
 import java.util.stream.Stream;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.junit.platform.engine.TestSource;
 import org.junit.platform.engine.support.descriptor.ClassSource;
@@ -122,13 +121,14 @@ void endToEndTests() {
 					/* 1 */ DisabledInAotRuntimeMethodLevelTests.class)));
 	}
 
-	@Disabled("Comment out to run all integration tests in spring-test in AOT mode")
+	// @Disabled("Comment out to run all integration tests in spring-test in AOT mode")
 	@Test
 	void endToEndTestsForEntireSpringTestModule() {
 		// AOT BUILD-TIME: CLASSPATH SCANNING
 		List<Class<?>> testClasses = createTestClassScanner()
 				// Scan all base packages in spring-test.
-				.scan("org.springframework.mock", "org.springframework.test")
+				// .scan("org.springframework.mock", "org.springframework.test")
+				.scan("org.springframework.test.context.bean.override")
 				// Or limit execution to a particular package and its subpackages.
 				//   - For example, to test JDBC support:
 				//     .scan("org.springframework.test.context.jdbc")
@@ -142,13 +142,14 @@ void endToEndTestsForEntireSpringTestModule() {
 				.toList();
 
 		// Optionally set failOnError flag to true to halt processing at the first failure.
-		runEndToEndTests(testClasses, false);
+		runEndToEndTests(testClasses, true);
 	}
 
-	@Disabled("Comment out to run @TestBean integration tests in AOT mode")
+	// @Disabled("Comment out to run @TestBean integration tests in AOT mode")
 	@Test
 	void endToEndTestsForTestBeanOverrideTestClasses() {
 		List<Class<?>> testClasses = List.of(
+				org.springframework.test.context.bean.override.convention.TestBeanForByTypeLookupIntegrationTests.class,
 				org.springframework.test.context.aot.samples.bean.override.convention.TestBeanJupiterTests.class,
 				org.springframework.test.context.bean.override.convention.TestBeanForByNameLookupIntegrationTests.class,
 				org.springframework.test.context.bean.override.convention.TestBeanForByNameLookupIntegrationTests.TestBeanFieldInEnclosingClassTests.class,
@@ -160,14 +161,20 @@ void endToEndTestsForTestBeanOverrideTestClasses() {
 		runEndToEndTests(testClasses, true);
 	}
 
-	@Disabled("Comment out to run selected integration tests in AOT mode")
+	// @Disabled("Comment out to run selected integration tests in AOT mode")
 	@Test
 	void endToEndTestsForSelectedTestClasses() {
 		List<Class<?>> testClasses = List.of(
-				org.springframework.test.context.bean.override.easymock.EasyMockBeanIntegrationTests.class,
-				org.springframework.test.context.bean.override.mockito.MockitoBeanForByNameLookupIntegrationTests.class,
-				org.springframework.test.context.junit4.SpringJUnit4ClassRunnerAppCtxTests.class,
-				org.springframework.test.context.junit4.ParameterizedDependencyInjectionTests.class
+				org.springframework.test.context.bean.override.mockito.MockitoBeanWithResetIntegrationTests.class,
+				org.springframework.test.context.bean.override.mockito.MockitoBeanForBeanFactoryIntegrationTests.class
+//				org.springframework.test.context.aot.samples.bean.override.convention.TestBeanJupiterTests.class,
+//				org.springframework.test.context.bean.override.easymock.EasyMockBeanIntegrationTests.class,
+//				org.springframework.test.context.bean.override.mockito.MockitoBeanForByNameLookupIntegrationTests.class,
+//				org.springframework.test.context.bean.override.mockito.MockitoBeanForByNameLookupIntegrationTests.MockitoBeanNestedTests.class,
+//				org.springframework.test.context.bean.override.mockito.MockitoSpyBeanForByNameLookupIntegrationTests.class,
+//				org.springframework.test.context.bean.override.mockito.MockitoSpyBeanForByNameLookupIntegrationTests.MockitoSpyBeanNestedTests.class
+//				org.springframework.test.context.junit4.SpringJUnit4ClassRunnerAppCtxTests.class,
+//				org.springframework.test.context.junit4.ParameterizedDependencyInjectionTests.class
 		);
 
 		runEndToEndTests(testClasses, true);

spring-test/src/test/java/org/springframework/test/context/bean/override/BeanOverrideBeanFactoryPostProcessorTests.java

@@ -51,6 +51,7 @@
  *
  * @author Simon Baslé
  * @author Stephane Nicoll
+ * @author Sam Brannen
  */
 class BeanOverrideBeanFactoryPostProcessorTests {
 
@@ -210,7 +211,7 @@ void allowReplaceDefinitionWhenSingletonDefinitionPresent() {
 	}
 
 	@Test
-	void copyDefinitionPrimaryFallbackAndScope() {
+	void beanDefinitionIsRetainedForNonFactoryBean() {
 		AnnotationConfigApplicationContext context = createContext(CaseByName.class);
 		context.getBeanFactory().registerScope("customScope", new SimpleThreadScope());
 		RootBeanDefinition definition = new RootBeanDefinition(String.class, () -> "ORIGINAL");
@@ -219,9 +220,23 @@ void copyDefinitionPrimaryFallbackAndScope() {
 		definition.setFallback(true);
 		context.registerBeanDefinition("descriptionBean", definition);
 
+		assertThatNoException().isThrownBy(context::refresh);
+		assertThat(context.getBeanDefinition("descriptionBean")).isSameAs(definition);
+	}
+
+	@Test
+	void primaryFallbackAndScopeAreCopiedForFactoryBean() {
+		AnnotationConfigApplicationContext context = createContext(CaseByName.class);
+		context.getBeanFactory().registerScope("customScope", new SimpleThreadScope());
+		RootBeanDefinition definition = new RootBeanDefinition(StringFactoryBean.class);
+		definition.setScope("customScope");
+		definition.setPrimary(true);
+		definition.setFallback(true);
+		context.registerBeanDefinition("descriptionBean", definition);
+
 		assertThatNoException().isThrownBy(context::refresh);
 		assertThat(context.getBeanDefinition("descriptionBean"))
-				.isNotSameAs(definition)
+				.isSameAs(definition)
 				.matches(BeanDefinition::isPrimary, "isPrimary")
 				.matches(BeanDefinition::isFallback, "isFallback")
 				.satisfies(d -> assertThat(d.getScope()).isEqualTo("customScope"))
@@ -327,6 +342,20 @@ public boolean isSingleton() {
 		}
 	}
 
+	static class StringFactoryBean implements FactoryBean<String> {
+
+		@Override
+		public String getObject() throws Exception {
+			return "enigma";
+		}
+
+		@Override
+		public Class<?> getObjectType() {
+			return String.class;
+		}
+
+	}
+
 	static class FactoryBeanRegisteringPostProcessor implements BeanFactoryPostProcessor, Ordered {
 
 		@Override