Support ContextLoader config in @⁠SpringJUnit[Web]Config

Prior to this commit, @⁠SpringJUnitConfig and @⁠SpringJUnitWebConfig
did not declare `loader` attributes that alias @⁠ContextConfiguration's
`loader` attribute. Consequently, it was not possible to configure a
custom ContextLoader via those annotations.

The lack of those `loader` attributes was an oversight, and this commit
introduces them to support custom ContextLoader configuration directly
via the @⁠SpringJUnitConfig and @⁠SpringJUnitWebConfig annotations.

Closes gh-31498

spring-test/src/main/java/org/springframework/test/context/junit/jupiter/SpringJUnitConfig.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -28,6 +28,7 @@ import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.core.annotation.AliasFor;
 import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.ContextLoader;
 
 /**
  * {@code @SpringJUnitConfig} is a <em>composed annotation</em> that combines
@@ -91,6 +92,13 @@ public @interface SpringJUnitConfig {
 	@AliasFor(annotation = ContextConfiguration.class)
 	boolean inheritInitializers() default true;
 
+	/**
+	 * Alias for {@link ContextConfiguration#loader}.
+	 * @since 6.1
+	 */
+	@AliasFor(annotation = ContextConfiguration.class)
+	Class<? extends ContextLoader> loader() default ContextLoader.class;
+
 	/**
 	 * Alias for {@link ContextConfiguration#name}.
 	 */

spring-test/src/main/java/org/springframework/test/context/junit/jupiter/web/SpringJUnitWebConfig.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -28,6 +28,7 @@ import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.context.ApplicationContextInitializer;
 import org.springframework.core.annotation.AliasFor;
 import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.ContextLoader;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
 import org.springframework.test.context.web.WebAppConfiguration;
 
@@ -96,6 +97,13 @@ public @interface SpringJUnitWebConfig {
 	@AliasFor(annotation = ContextConfiguration.class)
 	boolean inheritInitializers() default true;
 
+	/**
+	 * Alias for {@link ContextConfiguration#loader}.
+	 * @since 6.1
+	 */
+	@AliasFor(annotation = ContextConfiguration.class)
+	Class<? extends ContextLoader> loader() default ContextLoader.class;
+
 	/**
 	 * Alias for {@link ContextConfiguration#name}.
 	 */

spring-test/src/test/java/org/springframework/test/context/junit/jupiter/SpringExtensionParameterizedTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -27,6 +27,7 @@ import org.springframework.context.ApplicationContext;
 import org.springframework.test.context.junit.jupiter.comics.Cat;
 import org.springframework.test.context.junit.jupiter.comics.Dog;
 import org.springframework.test.context.junit.jupiter.comics.Person;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -40,7 +41,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @see SpringExtension
  * @see ParameterizedTest
  */
-@SpringJUnitConfig(TestConfig.class)
+@SpringJUnitConfig(classes = TestConfig.class, loader = AnnotationConfigContextLoader.class)
 class SpringExtensionParameterizedTests {
 
 	@ParameterizedTest

spring-test/src/test/java/org/springframework/test/context/junit/jupiter/web/WebSpringExtensionTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -21,6 +21,7 @@ import org.junit.jupiter.api.Test;
 
 import org.springframework.http.MediaType;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
+import org.springframework.test.context.web.AnnotationConfigWebContextLoader;
 import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.web.context.WebApplicationContext;
 
@@ -49,7 +50,7 @@ import static org.springframework.test.web.servlet.setup.MockMvcBuilders.webAppC
  * @see org.springframework.test.context.junit.jupiter.SpringExtensionTests
  * @see org.springframework.test.context.junit.jupiter.ComposedSpringExtensionTests
  */
-@SpringJUnitWebConfig(WebConfig.class)
+@SpringJUnitWebConfig(classes = WebConfig.class, loader = AnnotationConfigWebContextLoader.class)
 @DisplayName("Web SpringExtension Tests")
 class WebSpringExtensionTests {