Fix pattern extraction when MVC is using a PathPatternParser

Fixes gh-24874

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/web/mappings/servlet/RequestMappingConditionsDescription.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,6 +23,7 @@ import java.util.stream.Collectors;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.servlet.mvc.condition.MediaTypeExpression;
 import org.springframework.web.servlet.mvc.condition.NameValueExpression;
+import org.springframework.web.servlet.mvc.condition.PatternsRequestCondition;
 import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
 
 /**
@@ -53,11 +54,17 @@ public class RequestMappingConditionsDescription {
 		this.methods = requestMapping.getMethodsCondition().getMethods();
 		this.params = requestMapping.getParamsCondition().getExpressions().stream()
 				.map(NameValueExpressionDescription::new).collect(Collectors.toList());
-		this.patterns = requestMapping.getPatternsCondition().getPatterns();
+		this.patterns = extractPathPatterns(requestMapping);
 		this.produces = requestMapping.getProducesCondition().getExpressions().stream()
 				.map(MediaTypeExpressionDescription::new).collect(Collectors.toList());
 	}
 
+	private Set<String> extractPathPatterns(RequestMappingInfo requestMapping) {
+		PatternsRequestCondition patternsCondition = requestMapping.getPatternsCondition();
+		return (patternsCondition != null) ? patternsCondition.getPatterns()
+				: requestMapping.getPathPatternsCondition().getPatternValues();
+	}
+
 	public List<MediaTypeExpressionDescription> getConsumes() {
 		return this.consumes;
 	}

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/web/mappings/MappingsEndpointTests.java

 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -56,6 +56,9 @@ import org.springframework.web.reactive.function.server.RouterFunction;
 import org.springframework.web.reactive.function.server.ServerResponse;
 import org.springframework.web.servlet.DispatcherServlet;
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
+import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import org.springframework.web.util.pattern.PathPatternParser;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.BDDMockito.given;
@@ -94,6 +97,28 @@ class MappingsEndpointTests {
 				});
 	}
 
+	@Test
+	void servletWebMappingsWithPathPatternParser() {
+		Supplier<ConfigurableWebApplicationContext> contextSupplier = prepareContextSupplier();
+		new WebApplicationContextRunner(contextSupplier).withUserConfiguration(EndpointConfiguration.class,
+				ServletWebConfiguration.class, PathPatternParserConfiguration.class).run((context) -> {
+					ContextMappings contextMappings = contextMappings(context);
+					assertThat(contextMappings.getParentId()).isNull();
+					assertThat(contextMappings.getMappings()).containsOnlyKeys("dispatcherServlets", "servletFilters",
+							"servlets");
+					Map<String, List<DispatcherServletMappingDescription>> dispatcherServlets = mappings(
+							contextMappings, "dispatcherServlets");
+					assertThat(dispatcherServlets).containsOnlyKeys("dispatcherServlet");
+					List<DispatcherServletMappingDescription> handlerMappings = dispatcherServlets
+							.get("dispatcherServlet");
+					assertThat(handlerMappings).hasSize(1);
+					List<ServletRegistrationMappingDescription> servlets = mappings(contextMappings, "servlets");
+					assertThat(servlets).hasSize(1);
+					List<FilterRegistrationMappingDescription> filters = mappings(contextMappings, "servletFilters");
+					assertThat(filters).hasSize(1);
+				});
+	}
+
 	@Test
 	void servletWebMappingsWithAdditionalDispatcherServlets() {
 		Supplier<ConfigurableWebApplicationContext> contextSupplier = prepareContextSupplier();
@@ -260,4 +285,21 @@ class MappingsEndpointTests {
 
 	}
 
+	@Configuration
+	static class PathPatternParserConfiguration {
+
+		@Bean
+		WebMvcConfigurer pathPatternParserConfigurer() {
+			return new WebMvcConfigurer() {
+
+				@Override
+				public void configurePathMatch(PathMatchConfigurer configurer) {
+					configurer.setPatternParser(new PathPatternParser());
+				}
+
+			};
+		}
+
+	}
+
 }