Fixed type detection to avoid reuse of parent bean's targetType on child definition merge

Issue: SPR-10374

spring-beans/src/test/java/org/springframework/beans/factory/DefaultListableBeanFactoryTests.java

@@ -712,6 +712,20 @@ public class DefaultListableBeanFactoryTests {
 				factory.getMergedBeanDefinition("child"), factory.getMergedBeanDefinition("child"));
 	}
 
+	@Test
+	public void testGetTypeWorksAfterParentChildMerging() {
+		RootBeanDefinition parentDefinition = new RootBeanDefinition(TestBean.class);
+		ChildBeanDefinition childDefinition = new ChildBeanDefinition("parent", DerivedTestBean.class, null, null);
+
+		DefaultListableBeanFactory factory = new DefaultListableBeanFactory();
+		factory.registerBeanDefinition("parent", parentDefinition);
+		factory.registerBeanDefinition("child", childDefinition);
+		factory.freezeConfiguration();
+
+		assertEquals(TestBean.class, factory.getType("parent"));
+		assertEquals(DerivedTestBean.class, factory.getType("child"));
+	}
+
 	@Test
 	public void testNameAlreadyBound() {
 		DefaultListableBeanFactory lbf = new DefaultListableBeanFactory();