Expose mvcPatternParser bean in WebMvcConfigurationSupport

See gh-26427

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/PathMatchConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -63,6 +63,9 @@ public class PathMatchConfigurer {
 	@Nullable
 	private PathMatcher pathMatcher;
 
+	@Nullable
+	private PathPatternParser defaultPatternParser;
+
 	@Nullable
 	private UrlPathHelper defaultUrlPathHelper;
 
@@ -226,7 +229,7 @@ public class PathMatchConfigurer {
 	}
 
 	/**
-	 * Return the configure UrlPathHelper instance or a default (shared) instance.
+	 * Return the configure UrlPathHelper or a default, shared instance otherwise.
 	 * @since 5.3
 	 */
 	protected UrlPathHelper getUrlPathHelperOrDefault() {
@@ -240,7 +243,7 @@ public class PathMatchConfigurer {
 	}
 
 	/**
-	 * Return the configure PathMatcher instance or a default (shared) instance.
+	 * Return the configure PathMatcher or a default, shared, instance otherwise.
 	 * @since 5.3
 	 */
 	protected PathMatcher getPathMatcherOrDefault() {
@@ -253,4 +256,17 @@ public class PathMatchConfigurer {
 		return this.defaultPathMatcher;
 	}
 
+	/**
+	 * Return the configured PathPatternParser or a default, shared, instance otherwise.
+	 * @since 5.3.4
+	 */
+	public PathPatternParser getPatternParserOrDefault() {
+		if (this.patternParser != null) {
+			return this.patternParser;
+		}
+		if (this.defaultPatternParser == null) {
+			this.defaultPatternParser = new PathPatternParser();
+		}
+		return this.defaultPatternParser;
+	}
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/WebMvcConfigurationSupport.java

@@ -395,6 +395,17 @@ public class WebMvcConfigurationSupport implements ApplicationContextAware, Serv
 	protected void configurePathMatch(PathMatchConfigurer configurer) {
 	}
 
+	/**
+	 * Return a global {@link PathPatternParser} instance to use for parsing
+	 * patterns to match to the {@link org.springframework.http.server.RequestPath}.
+	 * The returned instance can be configured using
+	 * {@link #configurePathMatch(PathMatchConfigurer)}.
+	 * @since 5.3.4
+	 */
+	@Bean
+	public PathPatternParser mvcPatternParser() {
+		return getPathMatchConfigurer().getPatternParserOrDefault();
+	}
 
 	/**
 	 * Return a global {@link UrlPathHelper} instance which is used to resolve

spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfigurationTests.java

@@ -274,7 +274,6 @@ public class DelegatingWebMvcConfigurationTests {
 
 	@Test
 	public void configurePathPatternParser() {
-
 		PathPatternParser patternParser = new PathPatternParser();
 		PathMatcher pathMatcher = mock(PathMatcher.class);
 		UrlPathHelper pathHelper = mock(UrlPathHelper.class);
@@ -313,7 +312,9 @@ public class DelegatingWebMvcConfigurationTests {
 				webMvcConfig.mvcResourceUrlProvider());
 
 		assertThat(annotationsMapping).isNotNull();
-		assertThat(annotationsMapping.getPatternParser()).isSameAs(patternParser);
+		assertThat(annotationsMapping.getPatternParser())
+				.isSameAs(patternParser)
+				.isSameAs(webMvcConfig.mvcPatternParser());
 		configAssertion.accept(annotationsMapping.getUrlPathHelper(), annotationsMapping.getPathMatcher());
 
 		SimpleUrlHandlerMapping mapping = (SimpleUrlHandlerMapping) webMvcConfig.viewControllerHandlerMapping(
@@ -344,4 +345,5 @@ public class DelegatingWebMvcConfigurationTests {
 		assertThat(webMvcConfig.mvcResourceUrlProvider().getUrlPathHelper()).isSameAs(pathHelper);
 		assertThat(webMvcConfig.mvcResourceUrlProvider().getPathMatcher()).isSameAs(pathMatcher);
 	}
+
 }