Merge branch '2.3.x'

Closes gh-22856

Author: wilkinsona

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration.java

@@ -56,6 +56,7 @@
 import org.springframework.boot.autoconfigure.web.servlet.WebMvcProperties.Format;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.boot.convert.ApplicationConversionService;
+import org.springframework.boot.web.servlet.ServletRegistrationBean;
 import org.springframework.boot.web.servlet.filter.OrderedFormContentFilter;
 import org.springframework.boot.web.servlet.filter.OrderedHiddenHttpMethodFilter;
 import org.springframework.boot.web.servlet.filter.OrderedRequestContextFilter;
@@ -191,18 +192,22 @@ public static class WebMvcAutoConfigurationAdapter implements WebMvcConfigurer {
 
 		private final ObjectProvider<DispatcherServletPath> dispatcherServletPath;
 
+		private final ObjectProvider<ServletRegistrationBean<?>> servletRegistrations;
+
 		final ResourceHandlerRegistrationCustomizer resourceHandlerRegistrationCustomizer;
 
 		public WebMvcAutoConfigurationAdapter(ResourceProperties resourceProperties, WebMvcProperties mvcProperties,
 				ListableBeanFactory beanFactory, ObjectProvider<HttpMessageConverters> messageConvertersProvider,
 				ObjectProvider<ResourceHandlerRegistrationCustomizer> resourceHandlerRegistrationCustomizerProvider,
-				ObjectProvider<DispatcherServletPath> dispatcherServletPath) {
+				ObjectProvider<DispatcherServletPath> dispatcherServletPath,
+				ObjectProvider<ServletRegistrationBean<?>> servletRegistrations) {
 			this.resourceProperties = resourceProperties;
 			this.mvcProperties = mvcProperties;
 			this.beanFactory = beanFactory;
 			this.messageConvertersProvider = messageConvertersProvider;
 			this.resourceHandlerRegistrationCustomizer = resourceHandlerRegistrationCustomizerProvider.getIfAvailable();
 			this.dispatcherServletPath = dispatcherServletPath;
+			this.servletRegistrations = servletRegistrations;
 			this.mvcProperties.checkConfiguration();
 		}
 
@@ -239,14 +244,19 @@ public void configurePathMatch(PathMatchConfigurer configurer) {
 					this.mvcProperties.getPathmatch().isUseRegisteredSuffixPattern());
 			this.dispatcherServletPath.ifAvailable((dispatcherPath) -> {
 				String servletUrlMapping = dispatcherPath.getServletUrlMapping();
-				if (servletUrlMapping.equals("/")) {
+				if (servletUrlMapping.equals("/") && singleDispatcherServlet()) {
 					UrlPathHelper urlPathHelper = new UrlPathHelper();
 					urlPathHelper.setAlwaysUseFullPath(true);
 					configurer.setUrlPathHelper(urlPathHelper);
 				}
 			});
 		}
 
+		private boolean singleDispatcherServlet() {
+			return this.servletRegistrations.stream().map(ServletRegistrationBean::getServlet)
+					.filter(DispatcherServlet.class::isInstance).count() == 1;
+		}
+
 		@Override
 		@SuppressWarnings("deprecation")
 		public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfigurationTests.java

@@ -53,6 +53,7 @@
 import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
 import org.springframework.boot.web.server.WebServerFactoryCustomizerBeanPostProcessor;
 import org.springframework.boot.web.servlet.FilterRegistrationBean;
+import org.springframework.boot.web.servlet.ServletRegistrationBean;
 import org.springframework.boot.web.servlet.filter.OrderedFormContentFilter;
 import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
 import org.springframework.context.ApplicationContext;
@@ -84,6 +85,7 @@
 import org.springframework.web.filter.FormContentFilter;
 import org.springframework.web.filter.HiddenHttpMethodFilter;
 import org.springframework.web.filter.RequestContextFilter;
+import org.springframework.web.servlet.DispatcherServlet;
 import org.springframework.web.servlet.HandlerAdapter;
 import org.springframework.web.servlet.HandlerExceptionResolver;
 import org.springframework.web.servlet.HandlerMapping;
@@ -893,6 +895,23 @@ void urlPathHelperDoesNotUseFullPathWithServletMapping() {
 		});
 	}
 
+	@Test
+	void urlPathHelperDoesNotUseFullPathWithAdditionalDispatcherServlet() {
+		this.contextRunner.withUserConfiguration(AdditionalDispatcherServletConfiguration.class).run((context) -> {
+			UrlPathHelper urlPathHelper = context.getBean(UrlPathHelper.class);
+			assertThat(urlPathHelper).extracting("alwaysUseFullPath").isEqualTo(false);
+		});
+	}
+
+	@Test
+	void urlPathHelperDoesNotUseFullPathWithAdditionalUntypedDispatcherServlet() {
+		this.contextRunner.withUserConfiguration(AdditionalUntypedDispatcherServletConfiguration.class)
+				.run((context) -> {
+					UrlPathHelper urlPathHelper = context.getBean(UrlPathHelper.class);
+					assertThat(urlPathHelper).extracting("alwaysUseFullPath").isEqualTo(false);
+				});
+	}
+
 	private void assertCacheControl(AssertableWebApplicationContext context) {
 		Map<String, Object> handlerMap = getHandlerMap(context.getBean("resourceHandlerMapping", HandlerMapping.class));
 		assertThat(handlerMap).hasSize(2);
@@ -1276,4 +1295,24 @@ public void addCorsMappings(CorsRegistry registry) {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	static class AdditionalDispatcherServletConfiguration {
+
+		@Bean
+		ServletRegistrationBean<DispatcherServlet> additionalDispatcherServlet() {
+			return new ServletRegistrationBean<>(new DispatcherServlet());
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class AdditionalUntypedDispatcherServletConfiguration {
+
+		@Bean
+		ServletRegistrationBean<?> additionalDispatcherServlet() {
+			return new ServletRegistrationBean<>(new DispatcherServlet());
+		}
+
+	}
+
 }