Polish "Consider aliases when checking descendants"

See gh-14967

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/source/AliasedConfigurationPropertySource.java

@@ -16,8 +16,6 @@
 
 package org.springframework.boot.context.properties.source;
 
-import java.util.Set;
-
 import org.springframework.util.Assert;
 
 /**
@@ -60,16 +58,19 @@ class AliasedConfigurationPropertySource implements ConfigurationPropertySource
 		if (result != ConfigurationPropertyState.ABSENT) {
 			return result;
 		}
-		Set<ConfigurationPropertyName> aliasNames = this.aliases.getAllNames();
-		for (ConfigurationPropertyName configurationPropertyName : aliasNames) {
-			boolean descendantPresentInAlias = this.aliases
-					.getAliases(configurationPropertyName).stream()
-					.filter(name::isAncestorOf).findFirst().isPresent();
-			if (descendantPresentInAlias) {
-				ConfigurationProperty configurationProperty = this.getSource()
-						.getConfigurationProperty(configurationPropertyName);
-				if (configurationProperty != null) {
-					return ConfigurationPropertyState.PRESENT;
+		for (ConfigurationPropertyName alias : getAliases().getAliases(name)) {
+			ConfigurationPropertyState aliasResult = this.source
+					.containsDescendantOf(alias);
+			if (aliasResult != ConfigurationPropertyState.ABSENT) {
+				return aliasResult;
+			}
+		}
+		for (ConfigurationPropertyName from : getAliases()) {
+			for (ConfigurationPropertyName alias : getAliases().getAliases(from)) {
+				if (name.isAncestorOf(alias)) {
+					if (this.source.getConfigurationProperty(from) != null) {
+						return ConfigurationPropertyState.PRESENT;
+					}
 				}
 			}
 		}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/source/ConfigurationPropertyNameAliases.java

@@ -18,9 +18,9 @@ package org.springframework.boot.context.properties.source;
 
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedMultiValueMap;
@@ -34,7 +34,8 @@ import org.springframework.util.MultiValueMap;
  * @since 2.0.0
  * @see ConfigurationPropertySource#withAliases(ConfigurationPropertyNameAliases)
  */
-public final class ConfigurationPropertyNameAliases {
+public final class ConfigurationPropertyNameAliases
+		implements Iterable<ConfigurationPropertyName> {
 
 	private final MultiValueMap<ConfigurationPropertyName, ConfigurationPropertyName> aliases = new LinkedMultiValueMap<>();
 
@@ -75,8 +76,9 @@ public final class ConfigurationPropertyNameAliases {
 				.findFirst().orElse(null);
 	}
 
-	public Set<ConfigurationPropertyName> getAllNames() {
-		return this.aliases.keySet();
+	@Override
+	public Iterator<ConfigurationPropertyName> iterator() {
+		return this.aliases.keySet().iterator();
 	}
 
 }

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/source/AliasedConfigurationPropertySourceTests.java

@@ -16,11 +16,11 @@
 
 package org.springframework.boot.context.properties.source;
 
+import java.util.Collections;
+
 import org.junit.Test;
 import org.mockito.Answers;
 
-import org.springframework.boot.origin.Origin;
-
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -107,31 +107,19 @@ public class AliasedConfigurationPropertySourceTests {
 				.willReturn(ConfigurationPropertyState.ABSENT);
 		given(source.containsDescendantOf(ConfigurationPropertyName.of("bar")))
 				.willReturn(ConfigurationPropertyState.PRESENT);
-		ConfigurationPropertyName barBar = ConfigurationPropertyName.of("bar.bar");
-		given(source.getConfigurationProperty(barBar)).willReturn(
-				new ConfigurationProperty(barBar, "barBarValue", mock(Origin.class)));
 		ConfigurationPropertySource aliased = source
-				.withAliases(new ConfigurationPropertyNameAliases("bar.bar", "foo.foo"));
+				.withAliases(new ConfigurationPropertyNameAliases("foo", "bar"));
 		assertThat(aliased.containsDescendantOf(name))
 				.isEqualTo(ConfigurationPropertyState.PRESENT);
 	}
 
 	@Test
 	public void containsDescendantOfWhenPresentInAliasShouldReturnPresent() {
-		ConfigurationPropertyName name = ConfigurationPropertyName.of("baz");
-		ConfigurationPropertySource source = mock(ConfigurationPropertySource.class,
-				withSettings().defaultAnswer(Answers.CALLS_REAL_METHODS));
-		given(source.containsDescendantOf(name))
-				.willReturn(ConfigurationPropertyState.ABSENT);
-
-		ConfigurationPropertyName barFoo = ConfigurationPropertyName.of("bar.foo");
-
-		given(source.getConfigurationProperty(barFoo)).willReturn(
-				new ConfigurationProperty(barFoo, "barFooValue", mock(Origin.class)));
-
+		ConfigurationPropertySource source = new MapConfigurationPropertySource(
+				Collections.singletonMap("foo.bar", "foobar"));
 		ConfigurationPropertySource aliased = source
-				.withAliases(new ConfigurationPropertyNameAliases("bar.foo", "baz.foo"));
-		assertThat(aliased.containsDescendantOf(name))
+				.withAliases(new ConfigurationPropertyNameAliases("foo.bar", "baz.foo"));
+		assertThat(aliased.containsDescendantOf(ConfigurationPropertyName.of("baz")))
 				.isEqualTo(ConfigurationPropertyState.PRESENT);
 	}