Make UserDetailsService back off with AuthManagerResolver bean

See gh-28361

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/servlet/UserDetailsServiceAutoConfiguration.java

@@ -32,6 +32,7 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.AuthenticationManagerResolver;
 import org.springframework.security.authentication.AuthenticationProvider;
 import org.springframework.security.config.annotation.ObjectPostProcessor;
 import org.springframework.security.core.userdetails.User;
@@ -56,7 +57,8 @@ import org.springframework.util.StringUtils;
 @ConditionalOnClass(AuthenticationManager.class)
 @ConditionalOnBean(ObjectPostProcessor.class)
 @ConditionalOnMissingBean(
-		value = { AuthenticationManager.class, AuthenticationProvider.class, UserDetailsService.class },
+		value = { AuthenticationManager.class, AuthenticationProvider.class, UserDetailsService.class,
+				AuthenticationManagerResolver.class },
 		type = { "org.springframework.security.oauth2.jwt.JwtDecoder",
 				"org.springframework.security.oauth2.server.resource.introspection.OpaqueTokenIntrospector" })
 public class UserDetailsServiceAutoConfiguration {

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/security/servlet/UserDetailsServiceAutoConfigurationTests.java

@@ -30,11 +30,7 @@ import org.springframework.boot.test.system.OutputCaptureExtension;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
-import org.springframework.security.authentication.AuthenticationManager;
-import org.springframework.security.authentication.AuthenticationProvider;
-import org.springframework.security.authentication.ProviderManager;
-import org.springframework.security.authentication.TestingAuthenticationProvider;
-import org.springframework.security.authentication.TestingAuthenticationToken;
+import org.springframework.security.authentication.*;
 import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
 import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
 import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
@@ -155,6 +151,12 @@ class UserDetailsServiceAutoConfigurationTests {
 				.run(((context) -> assertThat(output).doesNotContain("Using generated security password: ")));
 	}
 
+	@Test
+	void userDetailsServiceShouldNotBePresentWhenAuthenticationManagerResolverBeanIsPresent() {
+		this.contextRunner.withUserConfiguration(TestAuthenticationManagerResolverConfiguration.class)
+				.run(((context) -> assertThat(context).doesNotHaveBean(InMemoryUserDetailsManager.class)));
+	}
+
 	private void testPasswordEncoding(Class<?> configClass, String providedPassword, String expectedPassword) {
 		this.contextRunner.withUserConfiguration(configClass)
 				.withPropertyValues("spring.security.user.password=" + providedPassword).run(((context) -> {
@@ -266,4 +268,14 @@ class UserDetailsServiceAutoConfigurationTests {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	static class TestAuthenticationManagerResolverConfiguration {
+
+		@Bean
+		AuthenticationManagerResolver<?> myAuthenticationManagerResolver() {
+			return mock(AuthenticationManagerResolver.class);
+		}
+
+	}
+
 }