Support @⁠MockitoSpyBean at the type level on test classes

This commit serves as a Proof of Concept.

See spring-projectsgh-34408

Author: sbrannen

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

@@ -45,8 +45,10 @@ public AbstractMockitoBeanOverrideHandler createHandler(Annotation overrideAnnot
 					"The @MockitoBean 'types' attribute must be omitted when declared on a field");
 			return new MockitoBeanOverrideHandler(field, ResolvableType.forField(field, testClass), mockitoBean);
 		}
-		else if (overrideAnnotation instanceof MockitoSpyBean spyBean) {
-			return new MockitoSpyBeanOverrideHandler(field, ResolvableType.forField(field, testClass), spyBean);
+		else if (overrideAnnotation instanceof MockitoSpyBean mockitoSpyBean) {
+			Assert.state(mockitoSpyBean.types().length == 0,
+					"The @MockitoSpyBean 'types' attribute must be omitted when declared on a field");
+			return new MockitoSpyBeanOverrideHandler(field, ResolvableType.forField(field, testClass), mockitoSpyBean);
 		}
 		throw new IllegalStateException("""
 				Invalid annotation passed to MockitoBeanOverrideProcessor: \
@@ -56,21 +58,33 @@ else if (overrideAnnotation instanceof MockitoSpyBean spyBean) {
 
 	@Override
 	public List<BeanOverrideHandler> createHandlers(Annotation overrideAnnotation, Class<?> testClass) {
-		if (!(overrideAnnotation instanceof MockitoBean mockitoBean)) {
-			throw new IllegalStateException("""
-					Invalid annotation passed to MockitoBeanOverrideProcessor: \
-					expected @MockitoBean on test class """ + testClass.getName());
+		if (overrideAnnotation instanceof MockitoBean mockitoBean) {
+			Class<?>[] types = mockitoBean.types();
+			Assert.state(types.length > 0,
+					"The @MockitoBean 'types' attribute must not be empty when declared on a class");
+			Assert.state(mockitoBean.name().isEmpty() || types.length == 1,
+					"The @MockitoBean 'name' attribute cannot be used when mocking multiple types");
+			List<BeanOverrideHandler> handlers = new ArrayList<>();
+			for (Class<?> type : types) {
+				handlers.add(new MockitoBeanOverrideHandler(ResolvableType.forClass(type), mockitoBean));
+			}
+			return handlers;
 		}
-		Class<?>[] types = mockitoBean.types();
-		Assert.state(types.length > 0,
-				"The @MockitoBean 'types' attribute must not be empty when declared on a class");
-		Assert.state(mockitoBean.name().isEmpty() || types.length == 1,
-				"The @MockitoBean 'name' attribute cannot be used when mocking multiple types");
-		List<BeanOverrideHandler> handlers = new ArrayList<>();
-		for (Class<?> type : types) {
-			handlers.add(new MockitoBeanOverrideHandler(ResolvableType.forClass(type), mockitoBean));
+		else if (overrideAnnotation instanceof MockitoSpyBean mockitoSpyBean) {
+			Class<?>[] types = mockitoSpyBean.types();
+			Assert.state(types.length > 0,
+					"The @MockitoSpyBean 'types' attribute must not be empty when declared on a class");
+			Assert.state(mockitoSpyBean.name().isEmpty() || types.length == 1,
+					"The @MockitoSpyBean 'name' attribute cannot be used when mocking multiple types");
+			List<BeanOverrideHandler> handlers = new ArrayList<>();
+			for (Class<?> type : types) {
+				handlers.add(new MockitoSpyBeanOverrideHandler(ResolvableType.forClass(type), mockitoSpyBean));
+			}
+			return handlers;
 		}
-		return handlers;
+		throw new IllegalStateException("""
+					Invalid annotation passed to MockitoBeanOverrideProcessor: \
+					expected either @MockitoBean or @MockitoSpyBean on test class """ + testClass.getName());
 	}
 
 }

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

@@ -18,6 +18,7 @@
 
 import java.lang.annotation.Documented;
 import java.lang.annotation.ElementType;
+import java.lang.annotation.Repeatable;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
@@ -66,9 +67,10 @@
  * @see org.springframework.test.context.bean.override.mockito.MockitoBean @MockitoBean
  * @see org.springframework.test.context.bean.override.convention.TestBean @TestBean
  */
-@Target(ElementType.FIELD)
+@Target({ElementType.FIELD, ElementType.TYPE})
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
+@Repeatable(MockitoSpyBeans.class)
 @BeanOverride(MockitoBeanOverrideProcessor.class)
 public @interface MockitoSpyBean {
 
@@ -91,6 +93,19 @@
 	@AliasFor("value")
 	String name() default "";
 
+	/**
+	 * One or more types to spy.
+	 * <p>Defaults to none.
+	 * <p>Each type specified will result in a spy being created and registered
+	 * with the {@code ApplicationContext}.
+	 * <p>Types must be omitted when the annotation is used on a field.
+	 * <p>When {@code @MockitoSpyBean} also defines a {@link #name}, this attribute
+	 * can only contain a single value.
+	 * @return the types to spy
+	 * @since 6.2.3
+	 */
+	Class<?>[] types() default {};
+
 	/**
 	 * The reset mode to apply to the spied bean.
 	 * <p>The default is {@link MockReset#AFTER} meaning that spies are automatically

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

@@ -48,7 +48,11 @@ class MockitoSpyBeanOverrideHandler extends AbstractMockitoBeanOverrideHandler {
 			new SpringAopBypassingVerificationStartedListener();
 
 
-	MockitoSpyBeanOverrideHandler(Field field, ResolvableType typeToSpy, MockitoSpyBean spyBean) {
+	MockitoSpyBeanOverrideHandler(ResolvableType typeToSpy, MockitoSpyBean spyBean) {
+		this(null, typeToSpy, spyBean);
+	}
+
+	MockitoSpyBeanOverrideHandler(@Nullable Field field, ResolvableType typeToSpy, MockitoSpyBean spyBean) {
 		super(field, typeToSpy, (StringUtils.hasText(spyBean.name()) ? spyBean.name() : null),
 				BeanOverrideStrategy.WRAP, spyBean.reset());
 		Assert.notNull(typeToSpy, "typeToSpy must not be null");

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

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2002-2025 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.mockito;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Container for {@link MockitoSpyBean @MockitoSpyBean} annotations which allows
+ * {@code @MockitoSpyBean} to be used as a {@linkplain java.lang.annotation.Repeatable
+ * repeatable annotation} at the type level — for example, on test classes
+ * or interfaces implemented by test classes.
+ *
+ * @author Sam Brannen
+ * @since 6.2.3
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface MockitoSpyBeans {
+
+	MockitoSpyBean[] value();
+
+}

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/TestInterface01.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockTestInterface01.java

@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
 
 @MockitoBean(types = Service01.class)
-interface TestInterface01 {
+interface MockTestInterface01 {
 }

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/TestInterface08.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockTestInterface08.java

@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
 
 @MockitoBean(types = Service08.class)
-interface TestInterface08 {
+interface MockTestInterface08 {
 }

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/TestInterface11.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockTestInterface11.java

@@ -14,10 +14,10 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
 
 @MockitoBean(types = Service11.class)
-interface TestInterface11 {
+interface MockTestInterface11 {
 }

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/MockitoBeansByNameIntegrationTests.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockitoBeansByNameIntegrationTests.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/MockitoBeansByTypeIntegrationTests.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockitoBeansByTypeIntegrationTests.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Nested;
@@ -27,6 +27,7 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.BDDMockito.given;
+import static org.springframework.test.mockito.MockitoAssertions.assertIsMock;
 
 /**
  * Integration tests for {@link MockitoBeans @MockitoBeans} and
@@ -42,7 +43,7 @@
 @MockitoBean(types = {Service04.class, Service05.class})
 @SharedMocks // Intentionally declared between local @MockitoBean declarations
 @MockitoBean(types = Service06.class)
-class MockitoBeansByTypeIntegrationTests implements TestInterface01 {
+class MockitoBeansByTypeIntegrationTests implements MockTestInterface01 {
 
 	@Autowired
 	Service01 service01;
@@ -79,6 +80,14 @@ void configureMocks() {
 
 	@Test
 	void checkMocks() {
+		assertIsMock(service01, "service01");
+		assertIsMock(service02, "service02");
+		assertIsMock(service03, "service03");
+		assertIsMock(service04, "service04");
+		assertIsMock(service05, "service05");
+		assertIsMock(service06, "service06");
+		assertIsMock(service07, "service07");
+
 		assertThat(service01.greeting()).isEqualTo("mock 01");
 		assertThat(service02.greeting()).isEqualTo("mock 02");
 		assertThat(service03.greeting()).isEqualTo("mock 03");
@@ -90,7 +99,7 @@ void checkMocks() {
 
 
 	@MockitoBean(types = Service09.class)
-	class BaseTestCase implements TestInterface08 {
+	class BaseTestCase implements MockTestInterface08 {
 
 		@Autowired
 		Service08 service08;
@@ -104,7 +113,7 @@ class BaseTestCase implements TestInterface08 {
 
 	@Nested
 	@MockitoBean(types = Service12.class)
-	class NestedTests extends BaseTestCase implements TestInterface11 {
+	class NestedTests extends BaseTestCase implements MockTestInterface11 {
 
 		@Autowired
 		Service11 service11;
@@ -128,6 +137,20 @@ void configureMocks() {
 
 		@Test
 		void checkMocks() {
+			assertIsMock(service01, "service01");
+			assertIsMock(service02, "service02");
+			assertIsMock(service03, "service03");
+			assertIsMock(service04, "service04");
+			assertIsMock(service05, "service05");
+			assertIsMock(service06, "service06");
+			assertIsMock(service07, "service07");
+			assertIsMock(service08, "service08");
+			assertIsMock(service09, "service09");
+			assertIsMock(service10, "service10");
+			assertIsMock(service11, "service11");
+			assertIsMock(service12, "service12");
+			assertIsMock(service13, "service13");
+
 			assertThat(service01.greeting()).isEqualTo("mock 01");
 			assertThat(service02.greeting()).isEqualTo("mock 02");
 			assertThat(service03.greeting()).isEqualTo("mock 03");

spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/mockbeans/MockitoBeansTests.java renamed to spring-test/src/test/java/org/springframework/test/context/bean/override/mockito/typelevel/MockitoBeansTests.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.test.context.bean.override.mockito.mockbeans;
+package org.springframework.test.context.bean.override.mockito.typelevel;
 
 import java.util.stream.Stream;