Move `DisableReactorResourceFactory...` to spring-boot-test

Move `DisableReactorResourceFactoryGlobalResources...` support from
`spring-boot-web-server-test` back to `spring-boot-test` since it's
useful if Reactor Netty is being used directly and removes the need
for the `spring-boot-web-server-test` dependency.

See gh-46356
See gh-47322

core/spring-boot-test/build.gradle

@@ -33,6 +33,7 @@ dependencies {
 	optional("jakarta.json.bind:jakarta.json.bind-api")
 	optional("jakarta.servlet:jakarta.servlet-api")
 	optional("junit:junit")
+	optional("io.projectreactor.netty:reactor-netty-http")
 	optional("org.assertj:assertj-core")
 	optional("org.hamcrest:hamcrest-core")
 	optional("org.hamcrest:hamcrest-library")

core/spring-boot-test/src/main/java/org/springframework/boot/test/http/client/DisableReactorResourceFactoryGlobalResourcesBeanPostProcessor.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.web.server.test.reactor.netty;
+package org.springframework.boot.test.http.client;
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.config.BeanPostProcessor;

core/spring-boot-test/src/main/java/org/springframework/boot/test/http/client/DisableReactorResourceFactoryGlobalResourcesContextCustomizerFactory.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.web.server.test.reactor.netty;
+package org.springframework.boot.test.http.client;
 
 import java.util.List;
 
@@ -36,12 +36,16 @@ import org.springframework.util.ClassUtils;
  */
 class DisableReactorResourceFactoryGlobalResourcesContextCustomizerFactory implements ContextCustomizerFactory {
 
-	String REACTOR_RESOURCE_FACTORY_CLASS = "org.springframework.http.client.ReactorResourceFactory";
+	private static final String REACTOR_RESOURCE_FACTORY_CLASS = "org.springframework.http.client.ReactorResourceFactory";
+
+	private static final String REACTOR_NETTY_CLASS = "reactor.netty.ReactorNetty";
 
 	@Override
 	public @Nullable ContextCustomizer createContextCustomizer(Class<?> testClass,
 			List<ContextConfigurationAttributes> configAttributes) {
-		if (ClassUtils.isPresent(this.REACTOR_RESOURCE_FACTORY_CLASS, testClass.getClassLoader())) {
+		ClassLoader classLoader = testClass.getClassLoader();
+		if (ClassUtils.isPresent(REACTOR_RESOURCE_FACTORY_CLASS, classLoader)
+				&& ClassUtils.isPresent(REACTOR_NETTY_CLASS, classLoader)) {
 			return new DisableReactorResourceFactoryGlobalResourcesContextCustomizerCustomizer();
 		}
 		return null;

core/spring-boot-test/src/main/java/org/springframework/boot/test/http/client/package-info.java

@@ -15,9 +15,9 @@
  */
 
 /**
- * Spring Boot support for testing Reactor Netty.
+ * Spring Boot support for HTTP client testing.
  */
 @NullMarked
-package org.springframework.boot.web.server.test.reactor.netty;
+package org.springframework.boot.test.http.client;
 
 import org.jspecify.annotations.NullMarked;

core/spring-boot-test/src/main/resources/META-INF/spring.factories

@@ -4,6 +4,7 @@ org.springframework.boot.test.context.ImportsContextCustomizerFactory,\
 org.springframework.boot.test.context.PropertyMappingContextCustomizerFactory,\
 org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizerFactory,\
 org.springframework.boot.test.context.filter.annotation.TypeExcludeFiltersContextCustomizerFactory,\
+org.springframework.boot.test.http.client.DisableReactorResourceFactoryGlobalResourcesContextCustomizerFactory,\
 org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory,\
 org.springframework.boot.test.web.reactive.client.WebTestClientContextCustomizerFactory,\
 org.springframework.boot.test.web.servlet.client.RestTestClientContextCustomizerFactory

core/spring-boot-test/src/test/java/org/springframework/boot/test/http/client/DisableReactorResourceFactoryGlobalResourcesContextCustomizerFactoryTests.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.boot.web.server.test.reactor.netty;
+package org.springframework.boot.test.http.client;
 
 import org.junit.jupiter.api.Test;
 

module/spring-boot-web-server-test/src/main/resources/META-INF/spring.factories

@@ -1,7 +1,3 @@
 # Environment Post Processors
 org.springframework.boot.EnvironmentPostProcessor=\
 org.springframework.boot.web.server.test.SpringBootTestRandomPortEnvironmentPostProcessor
-
-# Spring Test Context Customizer Factories
-org.springframework.test.context.ContextCustomizerFactory=\
-org.springframework.boot.web.server.test.reactor.netty.DisableReactorResourceFactoryGlobalResourcesContextCustomizerFactory