HHH-18681 Add test for issue

Author: dreab8

hibernate-core/src/test/java/org/hibernate/orm/test/query/SubQuerySelectCaseWhenTest.java

@@ -0,0 +1,79 @@
+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.query;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+
+@DomainModel(
+		annotatedClasses = {
+				SubQuerySelectCaseWhenTest.TestEntity.class,
+		}
+)
+@SessionFactory
+@JiraKey("HHH-18681")
+public class SubQuerySelectCaseWhenTest {
+
+	@BeforeEach
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					session.persist( new TestEntity( "A" ) );
+					session.persist( new TestEntity( "B" ) );
+					session.persist( new TestEntity( "C" ) );
+				}
+		);
+	}
+
+	@Test
+	public void testSelectCase(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			List<Integer> result = session.createQuery( "select "
+							+ "		(select "
+							+ "			case "
+							+ "				when "
+							+ "					t.name = ?1 "
+							+ "				then 0 "
+							+ "				else 1 "
+							+ "			end)"
+							+ " from TestEntity t order by t.name", Integer.class )
+					.setParameter( 1, "A" )
+					.list();
+			assertThat( result.size() ).isEqualTo( 3 );
+			assertThat( result.get( 0 ) ).isEqualTo( 0 );
+			assertThat( result.get( 1 ) ).isEqualTo( 1 );
+			assertThat( result.get( 2 ) ).isEqualTo( 1 );
+		} );
+	}
+
+	@Entity(name = "TestEntity")
+	public class TestEntity {
+
+		@Id
+		@GeneratedValue
+		private Long id;
+
+		private String name;
+
+		public TestEntity() {
+		}
+
+		public TestEntity(String name) {
+			this.name = name;
+		}
+	}
+}