Do not convert key nodes to originTrackedValue

Fixes gh-8540

spring-boot/src/main/java/org/springframework/boot/env/OriginTrackedYamlLoader.java

@@ -21,13 +21,16 @@ import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 import org.yaml.snakeyaml.DumperOptions;
 import org.yaml.snakeyaml.Yaml;
 import org.yaml.snakeyaml.constructor.BaseConstructor;
 import org.yaml.snakeyaml.constructor.Constructor;
 import org.yaml.snakeyaml.error.Mark;
+import org.yaml.snakeyaml.nodes.MappingNode;
 import org.yaml.snakeyaml.nodes.Node;
+import org.yaml.snakeyaml.nodes.NodeTuple;
 import org.yaml.snakeyaml.nodes.ScalarNode;
 import org.yaml.snakeyaml.nodes.Tag;
 import org.yaml.snakeyaml.representer.Representer;
@@ -92,7 +95,15 @@ class OriginTrackedYamlLoader extends YamlProcessor {
 		@Override
 		protected Object constructObject(Node node) {
 			if (node instanceof ScalarNode) {
-				return constructTrackedObject(node, super.constructObject(node));
+				if (!(node instanceof KeyScalarNode)) {
+					return constructTrackedObject(node, super.constructObject(node));
+				}
+			}
+			else if (node instanceof MappingNode) {
+				List<NodeTuple> value = ((MappingNode) node).getValue();
+				List<NodeTuple> updatedValues = value.stream().map(nt -> new NodeTuple(KeyScalarNode.get(nt.getKeyNode()),
+						nt.getValueNode())).collect(Collectors.toList());
+				((MappingNode) node).setValue(updatedValues);
 			}
 			return super.constructObject(node);
 		}
@@ -111,6 +122,24 @@ class OriginTrackedYamlLoader extends YamlProcessor {
 
 	}
 
+	/**
+	 * {@link ScalarNode} that replaces the key node in a {@link NodeTuple}.
+	 */
+	private static class KeyScalarNode extends ScalarNode {
+
+		KeyScalarNode(ScalarNode node) {
+			super(node.getTag(), node.getValue(), node.getStartMark(), node.getEndMark(), node.getStyle());
+		}
+
+		private static Node get(Node node) {
+			if (node instanceof ScalarNode) {
+				return new KeyScalarNode((ScalarNode) node);
+			}
+			return node;
+		}
+
+	}
+
 	/**
 	 * {@link Resolver} that limits {@link Tag#TIMESTAMP} tags.
 	 */

spring-boot/src/test/java/org/springframework/boot/env/OriginTrackedYamlLoaderTests.java

@@ -96,6 +96,22 @@ public class OriginTrackedYamlLoaderTests {
 		assertThat(result.get("name").toString()).isEqualTo("Test Name");
 	}
 
+	@Test
+	public void processListOfMaps() throws Exception {
+		OriginTrackedValue name = getValue("example.foo[0].name");
+		OriginTrackedValue url = getValue("example.foo[0].url");
+		OriginTrackedValue bar1 = getValue("example.foo[0].bar[0].bar1");
+		OriginTrackedValue bar2 = getValue("example.foo[0].bar[1].bar2");
+		assertThat(name.toString()).isEqualTo("springboot");
+		assertThat(getLocation(name)).isEqualTo("22:15");
+		assertThat(url.toString()).isEqualTo("http://springboot.com");
+		assertThat(getLocation(url)).isEqualTo("23:14");
+		assertThat(bar1.toString()).isEqualTo("baz");
+		assertThat(getLocation(bar1)).isEqualTo("25:19");
+		assertThat(bar2.toString()).isEqualTo("bling");
+		assertThat(getLocation(bar2)).isEqualTo("26:19");
+	}
+
 	private OriginTrackedValue getValue(String name) {
 		if (this.result == null) {
 			this.result = this.loader.load();

spring-boot/src/test/resources/org/springframework/boot/env/test-yaml.yml

@@ -17,6 +17,13 @@ education: |
     4 GCSEs
     3 A-Levels
     BSc in the Internet of Things
+example:
+    foo:
+      - name: springboot
+        url: http://springboot.com
+        bar:
+          - bar1: baz
+          - bar2: bling
 ---
 
 spring: