Revise documentation for @⁠ActiveProfiles and ActiveProfilesResolver

See gh-36269
See gh-36600

Author: sbrannen

framework-docs/modules/ROOT/pages/testing/annotations/integration-spring/annotation-activeprofiles.adoc

@@ -74,7 +74,7 @@ and registering it by using the `resolver` attribute of `@ActiveProfiles`.
 
 NOTE: When `@ActiveProfiles` is declared on a test class, the `spring.profiles.active`
 property (whether configured as a JVM system property or environment variable) is not
-taken into account by the Test Context Framework when determining active profiles. If
+taken into account by the TestContext Framework when determining active profiles. If
 you need to allow `spring.profiles.active` to override the profiles configured via
 `@ActiveProfiles`, you can implement a custom `ActiveProfilesResolver` as described in
 xref:testing/testcontext-framework/ctx-management/env-profiles.adoc[Context Configuration with Environment Profiles].

framework-docs/modules/ROOT/pages/testing/testcontext-framework/ctx-management/env-profiles.adoc

@@ -545,8 +545,8 @@ Kotlin::
 
 The following example demonstrates how to implement and register a custom
 `SystemPropertyOverrideActiveProfilesResolver` that allows the `spring.profiles.active`
-property (whether configured as a JVM system property or environment variable) to
-override profiles configured via `@ActiveProfiles`:
+property (when configured as a JVM system property) to override profiles configured via
+`@ActiveProfiles`:
 
 [tabs]
 ======
@@ -583,35 +583,45 @@ Kotlin::
 ======
 Java::
 +
-[source,java,indent=0,subs="verbatim,quotes",role="primary"]
+[source,java,indent=0,subs="verbatim,quotes",role="primary",fold="-imports"]
 ----
-	public class SystemPropertyOverrideActiveProfilesResolver implements ActiveProfilesResolver {
+	import org.springframework.core.env.AbstractEnvironment;
+	import org.springframework.test.context.support.DefaultActiveProfilesResolver;
+	import org.springframework.util.StringUtils;
+
+	public class SystemPropertyOverrideActiveProfilesResolver extends DefaultActiveProfilesResolver {
 
 		@Override
 		public String[] resolve(Class<?> testClass) {
-			String profiles = System.getProperty("spring.profiles.active");
-			if (profiles != null && !profiles.isBlank()) {
-				return profiles.split(",");
+			String profiles = System.getProperty(AbstractEnvironment.ACTIVE_PROFILES_PROPERTY_NAME);
+			if (StringUtils.hasText(profiles)) {
+				return StringUtils.commaDelimitedListToStringArray(
+						StringUtils.trimAllWhitespace(profiles));
 			}
-			return new DefaultActiveProfilesResolver().resolve(testClass);
+			return super.resolve(testClass);
 		}
 	}
 ----
 
 Kotlin::
 +
-[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary"]
+[source,kotlin,indent=0,subs="verbatim,quotes",role="secondary",fold="-imports"]
 ----
-	class SystemPropertyOverrideActiveProfilesResolver : ActiveProfilesResolver {
+	import org.springframework.core.env.AbstractEnvironment
+	import org.springframework.test.context.support.DefaultActiveProfilesResolver
+	import org.springframework.util.StringUtils
+
+	class SystemPropertyOverrideActiveProfilesResolver : DefaultActiveProfilesResolver() {
 
 		override fun resolve(testClass: Class<*>): Array<String> {
-			val profiles = System.getProperty("spring.profiles.active")
-			if (!profiles.isNullOrBlank()) {
-				return profiles.split(",").toTypedArray()
+			val profiles = System.getProperty(AbstractEnvironment.ACTIVE_PROFILES_PROPERTY_NAME)
+			if (StringUtils.hasText(profiles)) {
+				return StringUtils.commaDelimitedListToStringArray(
+					StringUtils.trimAllWhitespace(profiles)
+				)
 			}
-			return DefaultActiveProfilesResolver().resolve(testClass)
+			return super.resolve(testClass)
 		}
 	}
 ----
 ======
-

spring-test/src/main/java/org/springframework/test/context/ActiveProfiles.java

@@ -38,8 +38,9 @@
  * See {@link NestedTestConfiguration @NestedTestConfiguration} for details.
  *
  * <p>Note that when {@code @ActiveProfiles} is declared on a test class, the
- * {@code spring.profiles.active} property (whether configured as a JVM system
- * property or environment variable) is not taken into account by the Test Context
+ * {@link org.springframework.core.env.AbstractEnvironment#ACTIVE_PROFILES_PROPERTY_NAME
+ * spring.profiles.active} property (whether configured as a JVM system property
+ * or environment variable) is not taken into account by the Spring TestContext
  * Framework when determining active profiles. If you need to allow
  * {@code spring.profiles.active} to override the profiles configured via
  * {@code @ActiveProfiles}, you can implement a custom {@link ActiveProfilesResolver}
@@ -81,6 +82,9 @@
 	/**
 	 * The type of {@link ActiveProfilesResolver} to use for resolving the active
 	 * bean definition profiles programmatically.
+	 * <p>If not specified, the
+	 * {@link org.springframework.test.context.support.DefaultActiveProfilesResolver
+	 * DefaultActiveProfilesResolver} will be used.
 	 * @since 4.0
 	 * @see ActiveProfilesResolver
 	 */

spring-test/src/main/java/org/springframework/test/context/ActiveProfilesResolver.java

@@ -30,7 +30,8 @@
  * @author Sam Brannen
  * @author Michail Nikolaev
  * @since 4.0
- * @see ActiveProfiles
+ * @see ActiveProfiles @ActiveProfiles
+ * @see org.springframework.test.context.support.DefaultActiveProfilesResolver DefaultActiveProfilesResolver
  */
 @FunctionalInterface
 public interface ActiveProfilesResolver {
@@ -41,7 +42,7 @@ public interface ActiveProfilesResolver {
 	 * @param testClass the test class for which the profiles should be resolved;
 	 * never {@code null}
 	 * @return the bean definition profiles to use when loading the
-	 * {@code ApplicationContext}; never {@code null}
+	 * {@code ApplicationContext}; never {@code null} but potentially empty
 	 * @see ActiveProfiles#resolver
 	 * @see ActiveProfiles#inheritProfiles
 	 */

spring-test/src/main/java/org/springframework/test/context/support/DefaultActiveProfilesResolver.java

@@ -32,10 +32,12 @@
  * configured declaratively via {@link ActiveProfiles#profiles} or
  * {@link ActiveProfiles#value}.
  *
- * <p>Note that the {@code spring.profiles.active} property (whether configured
- * as a JVM system property or environment variable) is not taken into account by
- * this resolver. If you need to allow {@code spring.profiles.active} to override
- * profiles configured via {@link ActiveProfiles}, you can implement a custom
+ * <p>Note that the
+ * {@link org.springframework.core.env.AbstractEnvironment#ACTIVE_PROFILES_PROPERTY_NAME
+ * spring.profiles.active} property (whether configured as a JVM system property
+ * or environment variable) is not taken into account by this resolver. If you need
+ * to allow {@code spring.profiles.active} to override profiles configured via
+ * {@link ActiveProfiles @ActiveProfiles}, you can implement a custom
  * {@link ActiveProfilesResolver} and register it via {@link ActiveProfiles#resolver}.
  *
  * @author Sam Brannen