HHH-15839 Add test for issue

hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/treat/HqlTreatJoinTest.java

@@ -0,0 +1,128 @@
+package org.hibernate.orm.test.query.hql.treat;
+
+import java.util.List;
+
+import org.hibernate.query.spi.QueryImplementor;
+
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.MappedSuperclass;
+import jakarta.persistence.OneToOne;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+@DomainModel(
+		annotatedClasses = {
+				HqlTreatJoinTest.TestEntity.class,
+				HqlTreatJoinTest.JoinedEntity.class
+		}
+)
+@SessionFactory
+@TestForIssue(jiraKey = "HHH-15839")
+public class HqlTreatJoinTest {
+
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					JoinedEntity joined = new JoinedEntity( 1, "joined" );
+					TestEntity testEntity = new TestEntity( 2, "test", joined );
+
+					session.persist( testEntity );
+					session.persist( joined );
+
+				}
+		);
+
+	}
+
+	@Test
+	public void testTreatQuery(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					QueryImplementor<TestEntity> query = session.createQuery(
+							"select t from TestEntity t where treat(t.joined as JoinedEntity).id = ?1",
+							TestEntity.class
+					);
+					query.setParameter( 1, 1 );
+					List<TestEntity> result = query.list();
+					assertThat( result.size() ).isEqualTo( 1 );
+				}
+		);
+	}
+
+	@MappedSuperclass
+	public static abstract class AbstractEntity<T> {
+
+		public AbstractEntity() {
+		}
+
+		public AbstractEntity(T joined) {
+			this.joined = joined;
+		}
+
+		@OneToOne
+		private T joined;
+
+		public T getJoined() {
+			return joined;
+		}
+	}
+
+	@Entity(name = "TestEntity")
+	public static class TestEntity extends AbstractEntity<JoinedEntity> {
+		@Id
+		private long id;
+
+		private String name;
+
+		public TestEntity() {
+		}
+
+		public TestEntity(long id, String name, JoinedEntity joined) {
+			super( joined );
+			this.id = id;
+			this.name = name;
+		}
+
+		public long getId() {
+			return id;
+		}
+
+		public String getName() {
+			return name;
+		}
+	}
+
+	@Entity(name = "JoinedEntity")
+	public static class JoinedEntity {
+
+		@Id
+		private long id;
+
+		private String name;
+
+		public JoinedEntity() {
+		}
+
+		public JoinedEntity(long id, String name) {
+			this.id = id;
+			this.name = name;
+		}
+
+		public long getId() {
+			return id;
+		}
+
+		public String getName() {
+			return name;
+		}
+	}
+}