verify bidirectional collection circular reference detection

hibernate-core/src/test/java/org/hibernate/orm/test/manytomany/ManyToManyBidirectionalTest.java

@@ -0,0 +1,146 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later
+ * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
+ */
+package org.hibernate.orm.test.manytomany;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.JoinTable;
+import javax.persistence.ManyToMany;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.ServiceRegistry;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import org.hamcrest.core.IsCollectionContaining;
+import org.hamcrest.core.IsSame;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author Nathan Xu
+ */
+@DomainModel(
+		annotatedClasses = {
+				ManyToManyBidirectionalTest.Book.class,
+				ManyToManyBidirectionalTest.Author.class
+		}
+)
+@SessionFactory(generateStatistics = true)
+@ServiceRegistry
+@SuppressWarnings( "unused" )
+public class ManyToManyBidirectionalTest {
+
+	@BeforeEach
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Author author1 = new Author( 1 );
+			final Author author2 = new Author( 2 );
+
+			final Book bookByAuthor1 = new Book( 1 );
+			bookByAuthor1.addAuthor( author1 );
+
+			final Book bookByAuthor2 = new Book( 2 );
+			bookByAuthor2.addAuthor( author2 );
+
+			final Book bookByAuthor1AndAuthor2 = new Book( 3 );
+			bookByAuthor1AndAuthor2.addAuthor( author1 );
+			bookByAuthor1AndAuthor2.addAuthor( author2 );
+
+			session.save( author1 );
+			session.save( author2 );
+			session.save( bookByAuthor1 );
+			session.save( bookByAuthor2 );
+			session.save( bookByAuthor1AndAuthor2 );
+
+		} );
+	}
+
+	@AfterEach
+	public void tearDown(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			session.createQuery( "delete from Author" ).executeUpdate();
+			session.createQuery( "delete from Book" ).executeUpdate();
+		} );
+	}
+
+	@Test
+	public void testCircularReferenceDetection(SessionFactoryScope scope) {
+		scope.inTransaction(
+				session -> {
+					final List<Book> books = session.createQuery( "from Book b join fetch b.authors" , Book.class ).list();
+					books.forEach( book ->
+						book.authors.forEach( author ->
+							assertThat( author.books, IsCollectionContaining.hasItem( IsSame.sameInstance( book ) ) )
+						)
+					);
+
+					final List<Author> authors = session.createQuery( "from Author a join fetch a.books" , Author.class ).list();
+					authors.forEach( author ->
+						author.books.forEach( book ->
+							assertThat( book.authors, IsCollectionContaining.hasItem( IsSame.sameInstance( author ) ) )
+						)
+					);
+				}
+		);
+	}
+
+	@Entity(name = "Book")
+	public static class Book {
+
+		@Id
+		private int id;
+
+		public Book() {
+		}
+
+		public Book(int id) {
+			this.id = id;
+		}
+
+		@ManyToMany
+		@JoinTable(name = "book_author",
+				joinColumns = { @JoinColumn(name = "fk_book") },
+				inverseJoinColumns = { @JoinColumn(name = "fk_author") })
+		private Set<Author> authors = new HashSet<>();
+
+		public void addAuthor(Author author) {
+			authors.add( author );
+			author.books.add( this );
+		}
+	}
+
+	@Entity(name = "Author")
+	public static class Author {
+
+		@Id
+		private int id;
+
+		public Author() {
+		}
+
+		public Author(int id) {
+			this.id = id;
+		}
+
+		@ManyToMany(mappedBy = "authors")
+		private Set<Book> books = new HashSet<>();
+
+		public void addBook(Book book) {
+			books.add( book );
+			book.authors.add( this );
+		}
+	}
+
+}

hibernate-core/src/test/java/org/hibernate/orm/test/onetomany/OneToManyBidirectionalTest.java

@@ -29,6 +29,7 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.sameInstance;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
@@ -480,6 +481,21 @@ public class OneToManyBidirectionalTest {
 		);
 	}
 
+	@Test
+	public void testCircularReferenceDetection(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			List<Order> orders = session.createQuery(
+					"select o from Order o join fetch o.lineItems",
+					Order.class
+			).list();
+			orders.forEach( order ->
+				order.getLineItems().forEach( item ->
+					assertThat( item.getOrder(), sameInstance( order ) )
+				)
+			);
+		} );
+	}
+
 	@Entity(name = "Order")
 	@Table(name = "`Order`")
 	public static class Order {