HHH-16165 Add test for issue

hibernate-core/src/test/java/org/hibernate/orm/test/annotations/manytomany/ManyToManyOrderByTest.java

@@ -0,0 +1,149 @@
+package org.hibernate.orm.test.annotations.manytomany;
+
+import java.util.ArrayList;
+import java.util.List;
+
+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.Basic;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToMany;
+import jakarta.persistence.OrderBy;
+import jakarta.persistence.Table;
+import jakarta.persistence.Tuple;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+@DomainModel(
+		annotatedClasses = {
+				ManyToManyOrderByTest.Author.class,
+				ManyToManyOrderByTest.Book.class,
+		}
+)
+@SessionFactory
+@TestForIssue(jiraKey = "HHH-16165")
+public class ManyToManyOrderByTest {
+
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					Author author = new Author( "Iain M Banks" );
+					Book book1 = new Book( "Feersum Endjinn" );
+					Book book2 = new Book( "Use of Weapons" );
+					author.books.add( book1 );
+					author.books.add( book2 );
+					session.persist( book1 );
+					session.persist( book2 );
+					session.persist( author );
+				}
+		);
+	}
+
+	@Test
+	public void testQueryWithDistinct(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					Author author = session.createQuery(
+									"select distinct a from Author a left join fetch a.books",
+									Author.class
+							)
+							.getSingleResult();
+					assertThat( author ).isNotNull();
+				}
+		);
+	}
+
+	@Test
+	public void testQueryWithDistinct2(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					List<Tuple> results = session.createQuery(
+									"select distinct a, 1 from Author a left join fetch a.books",
+									Tuple.class
+							)
+							.list();
+					for ( Tuple t : results ) {
+						assertThat( t.getElements().size() ).isEqualTo( 2 );
+						assertThat( t.get( 0 ) ).isInstanceOf( Author.class );
+						assertThat( t.get( 1 ) ).isEqualTo( 1 );
+					}
+				}
+		);
+	}
+
+	@Test
+	public void testQuery(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					Author author = session.createQuery(
+									"select a from Author a left join fetch a.books",
+									Author.class
+							)
+							.getSingleResult();
+					assertThat( author ).isNotNull();
+				}
+		);
+	}
+
+	@Entity(name = "Book")
+	@Table(name = "MTMBook")
+	static class Book {
+
+		@GeneratedValue
+		@Id
+		long id;
+
+		@Basic(optional = false)
+		String title;
+
+		Book(String title) {
+			this.title = title;
+		}
+
+		Book() {
+		}
+	}
+
+	@Entity(name = "Author")
+	@Table(name = "MTMAuthor")
+	static class Author {
+
+		@GeneratedValue
+		@Id
+		long id;
+
+		@Basic(optional = false)
+		String name;
+
+		@ManyToMany
+		@OrderBy("id")
+		List<Book> books = new ArrayList<>();
+
+		Author(String name) {
+			this.name = name;
+		}
+
+		public Author() {
+		}
+
+		public long getId() {
+			return id;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public List<Book> getBooks() {
+			return books;
+		}
+	}
+}