DATAMONGO-2221 - Fix mapping of Strings matching a valid ObjectId for unresolvable paths.

We now make sure we to not convert Strings representing valid ObjectIds into the such for paths that cannot be resolved to a Property.

Original pull request: #732.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/convert/QueryMapper.java

@@ -914,9 +914,7 @@ public class QueryMapper {
 			MongoPersistentProperty idProperty = entity.getIdProperty();
 
 			if (idProperty != null) {
-
-				return name.equals(idProperty.getName()) || name.equals(idProperty.getFieldName())
-						|| name.endsWith("." + idProperty.getName()) || name.endsWith("." + idProperty.getFieldName());
+				return name.equals(idProperty.getName()) || name.equals(idProperty.getFieldName());
 			}
 
 			return DEFAULT_ID_NAMES.contains(name);
@@ -1004,14 +1002,15 @@ public class QueryMapper {
 		@Nullable
 		private PersistentPropertyPath<MongoPersistentProperty> getPath(String pathExpression) {
 
+			String rawPath = pathExpression.replaceAll("\\.\\d+", "");
+
+			PropertyPath path = forName(rawPath);
+			if (path == null || isPathToJavaLangClassProperty(path)) {
+				return null;
+			}
+
 			try {
 
-				PropertyPath path = PropertyPath.from(pathExpression.replaceAll("\\.\\d+", ""), entity.getTypeInformation());
-
-				if (isPathToJavaLangClassProperty(path)) {
-					return null;
-				}
-
 				PersistentPropertyPath<MongoPersistentProperty> propertyPath = mappingContext.getPersistentPropertyPath(path);
 
 				Iterator<MongoPersistentProperty> iterator = propertyPath.iterator();
@@ -1032,7 +1031,30 @@ public class QueryMapper {
 				}
 
 				return propertyPath;
+			} catch (InvalidPersistentPropertyPath e) {
+				return null;
+			}
+		}
+
+		/**
+		 * Querydsl happens to map id fields directly to {@literal _id} which breaks {@link PropertyPath} resolution. So if
+		 * the first attempt fails we try to replace {@literal _id} with just {@literal id} and see if we can resolve if
+		 * then.
+		 *
+		 * @param path
+		 * @return the path or {@literal null}
+		 */
+		@Nullable
+		private PropertyPath forName(String path) {
+
+			try {
+				return PropertyPath.from(path, entity.getTypeInformation());
 			} catch (PropertyReferenceException | InvalidPersistentPropertyPath e) {
+
+				if (path.endsWith("_id")) {
+					return forName(path.substring(0, path.length() - 3) + "id");
+				}
+
 				return null;
 			}
 		}

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/convert/QueryMapperUnitTests.java

@@ -831,6 +831,30 @@ public class QueryMapperUnitTests {
 		assertThat(document).isEqualTo(new org.bson.Document("nested.id", idHex));
 	}
 
+	@Test // DATAMONGO-2221
+	public void shouldNotConvertHexStringToObjectIdForRenamedDeeplyNestedIdField() {
+
+		String idHex = new ObjectId().toHexString();
+		Query query = new Query(where("nested.deeplyNested.id").is(idHex));
+
+		org.bson.Document document = mapper.getMappedObject(query.getQueryObject(),
+				context.getPersistentEntity(RootForClassWithExplicitlyRenamedIdField.class));
+
+		assertThat(document).isEqualTo(new org.bson.Document("nested.deeplyNested.id", idHex));
+	}
+
+	@Test // DATAMONGO-2221
+	public void shouldNotConvertHexStringToObjectIdForUnresolvablePath() {
+
+		String idHex = new ObjectId().toHexString();
+		Query query = new Query(where("nested.unresolvablePath.id").is(idHex));
+
+		org.bson.Document document = mapper.getMappedObject(query.getQueryObject(),
+				context.getPersistentEntity(RootForClassWithExplicitlyRenamedIdField.class));
+
+		assertThat(document).isEqualTo(new org.bson.Document("nested.unresolvablePath.id", idHex));
+	}
+
 	@Document
 	public class Foo {
 		@Id private ObjectId id;
@@ -926,6 +950,11 @@ public class QueryMapperUnitTests {
 	static class ClassWithExplicitlyRenamedField {
 
 		@Field("id") String id;
+		DeeplyNestedClassWithExplicitlyRenamedField deeplyNested;
+	}
+
+	static class DeeplyNestedClassWithExplicitlyRenamedField {
+		@Field("id") String id;
 	}
 
 	static class ClassWithGeoTypes {