Separate failure and success scenario tests for @⁠TestBean

This commit also ensures that @⁠Bean methods are declared within
@⁠Configuration classes instead of within test classes.

See spring-projectsgh-29122

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

@@ -0,0 +1,229 @@
+/*
+ * 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.convention;
+
+import org.junit.jupiter.api.Test;
+import org.junit.platform.engine.TestExecutionResult;
+import org.junit.platform.testkit.engine.EngineExecutionResults;
+import org.junit.platform.testkit.engine.EngineTestKit;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.aot.DisabledInAotMode;
+import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.fail;
+import static org.assertj.core.api.InstanceOfAssertFactories.THROWABLE;
+import static org.junit.platform.engine.discovery.DiscoverySelectors.selectClass;
+
+/**
+ * {@link TestBean @TestBean} integration tests for failure scenarios.
+ *
+ * @since 6.2
+ * @see TestBeanIntegrationTests
+ */
+public class FailingTestBeanIntegrationTests {
+
+	@Test
+	void testBeanFailingNoFieldNameBean() {
+		EngineExecutionResults results = EngineTestKit.engine("junit-jupiter")//
+				.selectors(selectClass(NoOriginalBeanTestCase.class))//
+				.execute();
+
+		assertThat(results.allEvents().failed().stream()).hasSize(1).first()
+				.satisfies(e -> assertThat(e.getRequiredPayload(TestExecutionResult.class)
+						.getThrowable()).get(THROWABLE)
+						.cause()
+						.isInstanceOf(IllegalStateException.class)
+						.hasMessage("Unable to override bean 'noOriginalBean'; " +
+								"there is no bean definition to replace with that name of type java.lang.String"));
+	}
+
+	@Test
+	void testBeanFailingNoExplicitNameBean() {
+		EngineExecutionResults results = EngineTestKit.engine("junit-jupiter")//
+				.selectors(selectClass(BeanDefinitionToOverrideNotPresentTestCase.class))//
+				.execute();
+
+		assertThat(results.allEvents().failed().stream()).hasSize(1).first()
+				.satisfies(e -> assertThat(e.getRequiredPayload(TestExecutionResult.class)
+						.getThrowable()).get(THROWABLE)
+						.cause()
+						.isInstanceOf(IllegalStateException.class)
+						.hasMessage("Unable to override bean 'notPresent'; " +
+								"there is no bean definition to replace with that name of type java.lang.String"));
+	}
+
+	@Test
+	void testBeanFailingNoImplicitMethod() {
+		Class<?> testClass = ExplicitTestOverrideMethodNotPresentTestCase.class;
+		EngineExecutionResults results = EngineTestKit.engine("junit-jupiter")//
+				.selectors(selectClass(testClass))//
+				.execute();
+
+		assertThat(results.allEvents().failed().stream()).hasSize(1).first()
+				.satisfies(e -> assertThat(e.getRequiredPayload(TestExecutionResult.class)
+						.getThrowable()).get(THROWABLE)
+						.rootCause().isInstanceOf(IllegalStateException.class)
+						.hasMessage("Failed to find a static test bean factory method in %s " +
+								"with return type java.lang.String whose name matches one of the " +
+								"supported candidates [notPresent]", testClass.getName()));
+	}
+
+	@Test
+	void testBeanFailingNoExplicitMethod() {
+		Class<?> testClass = ImplicitTestOverrideMethodNotPresentTestCase.class;
+		EngineExecutionResults results = EngineTestKit.engine("junit-jupiter")//
+				.selectors(selectClass(testClass))//
+				.execute();
+
+		assertThat(results.allEvents().failed().stream()).hasSize(1).first()
+				.satisfies(e -> assertThat(e.getRequiredPayload(TestExecutionResult.class)
+						.getThrowable()).get(THROWABLE)
+						.rootCause().isInstanceOf(IllegalStateException.class)
+						.hasMessage("Failed to find a static test bean factory method in %s " +
+								"with return type java.lang.String whose name matches one of the " +
+								"supported candidates [fieldTestOverride]", testClass.getName()));
+	}
+
+	@Test
+	void testBeanFailingBeanOfWrongType() {
+		EngineExecutionResults results = EngineTestKit.engine("junit-jupiter")//
+				.selectors(selectClass(BeanTypeMismatchTestCase.class))//
+				.execute();
+
+		assertThat(results.allEvents().failed().stream()).hasSize(1).first()
+				.satisfies(e -> assertThat(e.getRequiredPayload(TestExecutionResult.class)
+						.getThrowable()).get(THROWABLE)
+						.rootCause().isInstanceOf(IllegalStateException.class)
+						.hasMessage("Unable to override bean 'notString'; there is no bean definition to replace with " +
+								"that name of type java.lang.String"));
+	}
+
+	@Configuration
+	static class Config {
+
+		@Bean("field")
+		String bean1() {
+			return "prod";
+		}
+
+		@Bean("nestedField")
+		String bean2() {
+			return "nestedProd";
+		}
+
+		@Bean("methodRenamed1")
+		String bean3() {
+			return "Prod";
+		}
+
+		@Bean("methodRenamed2")
+		String bean4() {
+			return "NestedProd";
+		}
+	}
+
+	@SpringJUnitConfig
+	@DisabledInAotMode
+	static class NoOriginalBeanTestCase {
+
+		@TestBean(name = "noOriginalBean")
+		String noOriginalBean;
+
+		@Test
+		void ignored() {
+			fail("should fail earlier");
+		}
+
+		static String noOriginalBeanTestOverride() {
+			return "should be ignored";
+		}
+
+	}
+
+	@SpringJUnitConfig
+	@DisabledInAotMode
+	static class BeanDefinitionToOverrideNotPresentTestCase {
+
+		@TestBean(name = "notPresent")
+		String field;
+
+		@Test
+		void ignored() {
+			fail("should fail earlier");
+		}
+
+		static String notPresentTestOverride() {
+			return "should be ignored";
+		}
+	}
+
+	@SpringJUnitConfig
+	@DisabledInAotMode
+	static class ExplicitTestOverrideMethodNotPresentTestCase {
+
+		@TestBean(methodName = "notPresent")
+		String field;
+
+		@Test
+		void ignored() {
+			fail("should fail earlier");
+		}
+	}
+
+	@SpringJUnitConfig
+	@DisabledInAotMode
+	static class ImplicitTestOverrideMethodNotPresentTestCase {
+
+		@TestBean //expects fieldTestOverride method
+		String field;
+
+		@Test
+		void ignored() {
+			fail("should fail earlier");
+		}
+	}
+
+	@SpringJUnitConfig
+	@DisabledInAotMode
+	static class BeanTypeMismatchTestCase {
+
+		@TestBean(name = "notString")
+		String field;
+
+		@Test
+		void ignored() {
+			fail("should fail earlier");
+		}
+
+		static String fieldTestOverride() {
+			return "should be ignored";
+		}
+
+		@Configuration
+		static class Config {
+
+			@Bean("notString")
+			StringBuilder bean1() {
+				return new StringBuilder("not a String");
+			}
+		}
+	}
+
+}