Updates to WebMVC fragment rendering API

See gh-33162

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ModelAndViewMethodReturnValueHandlerTests.java

@@ -17,6 +17,8 @@
 package org.springframework.web.servlet.mvc.method.annotation;
 
 import java.lang.reflect.Method;
+import java.util.Collection;
+import java.util.List;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -26,7 +28,9 @@ import org.springframework.ui.ModelMap;
 import org.springframework.web.context.request.ServletWebRequest;
 import org.springframework.web.method.support.ModelAndViewContainer;
 import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.servlet.SmartView;
 import org.springframework.web.servlet.mvc.support.RedirectAttributesModelMap;
+import org.springframework.web.servlet.view.FragmentsRendering;
 import org.springframework.web.servlet.view.RedirectView;
 import org.springframework.web.testfixture.servlet.MockHttpServletRequest;
 
@@ -60,6 +64,9 @@ class ModelAndViewMethodReturnValueHandlerTests {
 	@Test
 	void supportsReturnType() throws Exception {
 		assertThat(handler.supportsReturnType(returnParamModelAndView)).isTrue();
+		assertThat(handler.supportsReturnType(getReturnValueParam("fragmentsRendering"))).isTrue();
+		assertThat(handler.supportsReturnType(getReturnValueParam("fragmentsCollection"))).isTrue();
+
 		assertThat(handler.supportsReturnType(getReturnValueParam("viewName"))).isFalse();
 	}
 
@@ -81,6 +88,22 @@ class ModelAndViewMethodReturnValueHandlerTests {
 		assertThat(mavContainer.getModel().get("attrName")).isEqualTo("attrValue");
 	}
 
+	@Test
+	void handleFragmentsRendering() throws Exception {
+		FragmentsRendering rendering = FragmentsRendering.with("viewName").build();
+
+		handler.handleReturnValue(rendering, returnParamModelAndView, mavContainer, webRequest);
+		assertThat(mavContainer.getView()).isInstanceOf(SmartView.class);
+	}
+
+	@Test
+	void handleFragmentsCollection() throws Exception {
+		Collection<ModelAndView> fragments = List.of(new ModelAndView("viewName"));
+
+		handler.handleReturnValue(fragments, returnParamModelAndView, mavContainer, webRequest);
+		assertThat(mavContainer.getView()).isInstanceOf(SmartView.class);
+	}
+
 	@Test
 	void handleNull() throws Exception {
 		handler.handleReturnValue(null, returnParamModelAndView, mavContainer, webRequest);
@@ -173,4 +196,14 @@ class ModelAndViewMethodReturnValueHandlerTests {
 		return null;
 	}
 
+	@SuppressWarnings("unused")
+	FragmentsRendering fragmentsRendering() {
+		return null;
+	}
+
+	@SuppressWarnings("unused")
+	Collection<ModelAndView> fragmentsCollection() {
+		return null;
+	}
+
 }

spring-webmvc/src/test/java/org/springframework/web/servlet/view/DefaultFragmentsRenderingTests.java

@@ -38,12 +38,12 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.condition.JRE.JAVA_21;
 
 /**
- * Tests for rendering through {@link FragmentsView}.
+ * Tests for rendering through {@link DefaultFragmentsRendering}.
  *
  * @author Rossen Stoyanchev
  */
 @DisabledForJreRange(min = JAVA_21, disabledReason = "Kotlin doesn't support Java 21+ yet")
-public class FragmentsViewTests {
+public class DefaultFragmentsRenderingTests {
 
 
 	@Test
@@ -59,7 +59,7 @@ public class FragmentsViewTests {
 		MockHttpServletRequest request = new MockHttpServletRequest();
 		MockHttpServletResponse response = new MockHttpServletResponse();
 
-		FragmentsView view = FragmentsView.create(List.of(
+		DefaultFragmentsRendering view = new DefaultFragmentsRendering(List.of(
 				new ModelAndView("fragment1", Map.of("foo", "Foo")),
 				new ModelAndView("fragment2", Map.of("bar", "Bar"))));