Handle unresolved view name

spring-web-reactive/src/main/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandler.java

@@ -151,6 +151,7 @@ public class ViewResolutionResultHandler implements HandlerResultHandler, Ordere
 				return Flux.fromIterable(getViewResolvers())
 						.concatMap(resolver -> resolver.resolveViewName(viewName, locale))
 						.next()
+						.otherwiseIfEmpty(handleUnresolvedViewName(viewName))
 						.then(view -> {
 							Flux<DataBuffer> body = view.render(result, null, exchange);
 							return exchange.getResponse().setBody(body);
@@ -201,4 +202,9 @@ public class ViewResolutionResultHandler implements HandlerResultHandler, Ordere
 		return StringUtils.stripFilenameExtension(path);
 	}
 
+	private Mono<View> handleUnresolvedViewName(String viewName) {
+		return Mono.error(new IllegalStateException(
+				"Could not resolve view with name '" + viewName + "'."));
+	}
+
 }

spring-web-reactive/src/test/java/org/springframework/web/reactive/result/view/ViewResolutionResultHandlerTests.java

@@ -154,9 +154,8 @@ public class ViewResolutionResultHandlerTests {
 
 	@Test
 	public void viewNameUnresolved() throws Exception {
-		TestSubscriber<Void> subscriber = handle("/path", "account", ResolvableType.forClass(String.class));
-
-		subscriber.assertNoValues();
+		handle("/path", "account", ResolvableType.forClass(String.class))
+				.assertErrorMessage("Could not resolve view with name 'account'.");
 	}
 
 	@Test