Discover @DynamicPropertySource methods on enclosing test classes

gh-19930 introduced support for finding class-level test configuration
annotations on enclosing classes when using JUnit Jupiter @Nested test
classes, but support for @DynamicPropertySource methods got overlooked
since they are method-level annotations.

This commit addresses this shortcoming by introducing full support for
@NestedTestConfiguration semantics for @DynamicPropertySource methods
on enclosing classes.

Closes gh-26091

spring-test/src/main/java/org/springframework/test/context/DynamicPropertySource.java

@@ -41,6 +41,11 @@ import java.lang.annotation.Target;
  * is resolved. Typically, method references are used to supply values, as in the
  * example below.
  *
+ * <p>As of Spring Framework 5.3.2, dynamic properties from methods annotated with
+ * {@code @DynamicPropertySource} will be <em>inherited</em> from enclosing test
+ * classes, analogous to inheritance from superclasses and interfaces. See
+ * {@link NestedTestConfiguration @NestedTestConfiguration} for details.
+ *
  * <p><strong>NOTE</strong>: if you use {@code @DynamicPropertySource} in a base
  * class and discover that tests in subclasses fail because the dynamic properties
  * change between subclasses, you may need to annotate your base class with

spring-test/src/main/java/org/springframework/test/context/NestedTestConfiguration.java

@@ -74,6 +74,7 @@ import org.springframework.lang.Nullable;
  * <li>{@link org.springframework.test.context.web.WebAppConfiguration @WebAppConfiguration}</li>
  * <li>{@link ActiveProfiles @ActiveProfiles}</li>
  * <li>{@link TestPropertySource @TestPropertySource}</li>
+ * <li>{@link DynamicPropertySource @DynamicPropertySource}</li>
  * <li>{@link org.springframework.test.annotation.DirtiesContext @DirtiesContext}</li>
  * <li>{@link org.springframework.transaction.annotation.Transactional @Transactional}</li>
  * <li>{@link org.springframework.test.annotation.Rollback @Rollback}</li>

spring-test/src/main/java/org/springframework/test/context/support/DynamicPropertiesContextCustomizerFactory.java

@@ -17,6 +17,7 @@
 package org.springframework.test.context.support;
 
 import java.lang.reflect.Method;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Set;
 
@@ -26,12 +27,14 @@ import org.springframework.lang.Nullable;
 import org.springframework.test.context.ContextConfigurationAttributes;
 import org.springframework.test.context.ContextCustomizerFactory;
 import org.springframework.test.context.DynamicPropertySource;
+import org.springframework.test.context.TestContextAnnotationUtils;
 
 /**
  * {@link ContextCustomizerFactory} to support
  * {@link DynamicPropertySource @DynamicPropertySource} methods.
  *
  * @author Phillip Webb
+ * @author Sam Brannen
  * @since 5.2.5
  * @see DynamicPropertiesContextCustomizer
  */
@@ -42,13 +45,21 @@ class DynamicPropertiesContextCustomizerFactory implements ContextCustomizerFact
 	public DynamicPropertiesContextCustomizer createContextCustomizer(Class<?> testClass,
 			List<ContextConfigurationAttributes> configAttributes) {
 
-		Set<Method> methods = MethodIntrospector.selectMethods(testClass, this::isAnnotated);
+		Set<Method> methods = new LinkedHashSet<>();
+		findMethods(testClass, methods);
 		if (methods.isEmpty()) {
 			return null;
 		}
 		return new DynamicPropertiesContextCustomizer(methods);
 	}
 
+	private void findMethods(Class<?> testClass, Set<Method> methods) {
+		methods.addAll(MethodIntrospector.selectMethods(testClass, this::isAnnotated));
+		if (TestContextAnnotationUtils.searchEnclosingClass(testClass)) {
+			findMethods(testClass.getEnclosingClass(), methods);
+		}
+	}
+
 	private boolean isAnnotated(Method method) {
 		return MergedAnnotations.from(method).isPresent(DynamicPropertySource.class);
 	}