Use leaf property when validating case-insensitive transformation in query derivation.

We now use the correct leaf property instead of using the root property (owning segment).

Closes #4087

Author: mp911de

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/JpaQueryCreator.java

@@ -491,7 +491,7 @@ public JpqlQueryBuilder.Predicate build() {
 				case NOT_LIKE:
 
 					PartTreeParameterBinding parameter = provider.next(part, String.class);
-					JpqlQueryBuilder.Expression parameterExpression = potentiallyIgnoreCase(part.getProperty(),
+					JpqlQueryBuilder.Expression parameterExpression = potentiallyIgnoreCase(part.getProperty().getLeafProperty(),
 							placeholder(parameter));
 
 					// Predicate like = builder.like(propertyExpression, parameterExpression, escape.getEscapeCharacter());
@@ -512,7 +512,8 @@ public JpqlQueryBuilder.Predicate build() {
 						return type.equals(SIMPLE_PROPERTY) ? where.isNull() : where.isNotNull();
 					}
 
-					JpqlQueryBuilder.Expression expression = potentiallyIgnoreCase(property, placeholder(simple));
+					JpqlQueryBuilder.Expression expression = potentiallyIgnoreCase(property.getLeafProperty(),
+							placeholder(simple));
 					return type.equals(SIMPLE_PROPERTY) ? whereIgnoreCase.eq(expression) : whereIgnoreCase.neq(expression);
 				case IS_EMPTY:
 				case IS_NOT_EMPTY:
@@ -624,7 +625,7 @@ private static String getDistanceFunction(ScoringFunction scoringFunction) {
 		 * @return
 		 */
 		private <T> JpqlQueryBuilder.Expression potentiallyIgnoreCase(JpqlQueryBuilder.Origin source, PropertyPath path) {
-			return potentiallyIgnoreCase(path, JpqlQueryBuilder.expression(source, path));
+			return potentiallyIgnoreCase(path.getLeafProperty(), JpqlQueryBuilder.expression(source, path));
 		}
 
 		/**
@@ -635,7 +636,7 @@ private <T> JpqlQueryBuilder.Expression potentiallyIgnoreCase(JpqlQueryBuilder.O
 		 * @return
 		 */
 		private <T> JpqlQueryBuilder.Expression potentiallyIgnoreCase(JpqlQueryBuilder.PathExpression path) {
-			return potentiallyIgnoreCase(path.getPropertyPath(), path);
+			return potentiallyIgnoreCase(path.getPropertyPath().getLeafProperty(), path);
 		}
 
 		/**

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/JpaQueryCreatorTests.java

@@ -19,6 +19,8 @@
 import static org.mockito.Mockito.*;
 
 import jakarta.persistence.ElementCollection;
+import jakarta.persistence.Embeddable;
+import jakarta.persistence.Embedded;
 import jakarta.persistence.EntityManager;
 import jakarta.persistence.Id;
 import jakarta.persistence.ManyToOne;
@@ -67,7 +69,7 @@
 class JpaQueryCreatorTests {
 
 	private static final TestMetaModel ORDER = TestMetaModel.hibernateModel(Order.class, LineItem.class, Product.class);
-	private static final TestMetaModel PERSON = TestMetaModel.hibernateModel(Person.class);
+	private static final TestMetaModel PERSON = TestMetaModel.hibernateModel(Person.class, EmailAddress.class);
 	private static final TestMetaModel REFERENCE_IDS = TestMetaModel.hibernateModel(
 			ReferencingEmbeddedIdExampleEmployee.class, EmbeddedIdExampleEmployee.class, EmbeddedIdExampleEmployeePK.class,
 			EmbeddedIdExampleDepartment.class);
@@ -716,7 +718,8 @@ void tupleProjection(Class<?> resultType) {
 				.returning(resultType) //
 				.withParameters("chris") //
 				.as(QueryCreatorTester::create) //
-				.expectJpql("SELECT p.id id, p.firstname firstname, p.lastname lastname FROM %s p WHERE p.firstname = ?1",
+				.expectJpql(
+						"SELECT p.id id, p.emailAddress emailAddress, p.firstname firstname, p.lastname lastname FROM %s p WHERE p.firstname = ?1",
 						DefaultJpaEntityMetadata.unqualify(Person.class)) //
 				.validateQuery();
 	}
@@ -769,6 +772,18 @@ void createsJoinForReferenceName() {
 				.validateQuery();
 	}
 
+	@Test // GH-4087
+	void considersLeafPropertyTypeForIgnoreCase() {
+
+		queryCreator(PERSON) //
+				.forTree(Person.class, "findByEmailAddress_EmailIgnoreCase") //
+				.withParameters("foo") //
+				.as(QueryCreatorTester::create) //
+				.expectJpql(
+						"SELECT p FROM JpaQueryCreatorTests$Person p INNER JOIN p.emailAddress e WHERE UPPER(e.email) = UPPER(?1)") //
+				.validateQuery();
+	}
+
 	QueryCreatorBuilder queryCreator(Metamodel metamodel) {
 		return new DefaultCreatorBuilder(metamodel);
 	}
@@ -838,6 +853,13 @@ static class Person {
 		@Id Long id;
 		String firstname;
 		String lastname;
+
+		@Embedded EmailAddress emailAddress;
+	}
+
+	@Embeddable
+	static class EmailAddress {
+		String email;
 	}
 
 	@jakarta.persistence.Entity