Polish 'Don't detect CloudPlatform when property is set'

See gh-25455

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/cloud/CloudPlatform.java

@@ -140,7 +140,8 @@ public enum CloudPlatform {
 	 * @return if the platform is active.
 	 */
 	public boolean isActive(Environment environment) {
-		return isEnforced(environment) || (isAutoDetectionEnabled(environment) && isDetected(environment));
+		String platformProperty = environment.getProperty(PROPERTY_NAME);
+		return isEnforced(platformProperty) || (platformProperty == null && isDetected(environment));
 	}
 
 	/**
@@ -151,7 +152,10 @@ public enum CloudPlatform {
 	 * @since 2.3.0
 	 */
 	public boolean isEnforced(Environment environment) {
-		String platform = environment.getProperty(PROPERTY_NAME);
+		return isEnforced(environment.getProperty(PROPERTY_NAME));
+	}
+
+	private boolean isEnforced(String platform) {
 		return name().equalsIgnoreCase(platform);
 	}
 
@@ -164,16 +168,6 @@ public enum CloudPlatform {
 	 */
 	public abstract boolean isDetected(Environment environment);
 
-	/**
-	 * Determines if it is enabled that the platform is detected by looking for
-	 * platform-specific environment variables.
-	 * @param environment the environment
-	 * @return if the platform auto-detection is enabled.
-	 */
-	private boolean isAutoDetectionEnabled(Environment environment) {
-		return environment.getProperty(PROPERTY_NAME) == null;
-	}
-
 	/**
 	 * Returns if the platform is behind a load balancer and uses
 	 * {@literal X-Forwarded-For} headers.

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/cloud/CloudPlatformTests.java

@@ -18,9 +18,7 @@ package org.springframework.boot.cloud;
 
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
-import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 import org.junit.jupiter.api.Test;
@@ -148,9 +146,8 @@ class CloudPlatformTests {
 		envVars.put("EXAMPLE_SERVICE_PORT", "8080");
 		Environment environment = getEnvironmentWithEnvVariables(envVars);
 		((MockEnvironment) environment).setProperty("spring.main.cloud-platform", "none");
-		List<CloudPlatform> activeCloudPlatforms = Stream.of(CloudPlatform.values())
-				.filter((cloudPlatform) -> cloudPlatform.isActive(environment)).collect(Collectors.toList());
-		assertThat(activeCloudPlatforms).containsExactly(CloudPlatform.NONE);
+		assertThat(Stream.of(CloudPlatform.values()).filter((platform) -> platform.isActive(environment)))
+				.containsExactly(CloudPlatform.NONE);
 	}
 
 	private Environment getEnvironmentWithEnvVariables(Map<String, Object> environmentVariables) {