HHH-18399 Add test for issue

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/onetoone/OneToOneJoinTableSelfReferenceTest.java

@@ -0,0 +1,93 @@
+/*
+ * 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.mapping.onetoone;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.Jira;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.JoinTable;
+import jakarta.persistence.OneToOne;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Marco Belladelli
+ */
+@DomainModel( annotatedClasses = OneToOneJoinTableSelfReferenceTest.Person.class )
+@SessionFactory
+@Jira( "https://hibernate.atlassian.net/browse/HHH-18399" )
+public class OneToOneJoinTableSelfReferenceTest {
+	@Test
+	public void testMapping(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Person parent = new Person();
+			parent.setId( 2L );
+
+			final Person child = new Person();
+			child.setId( 1L );
+			parent.setChild( child );
+
+			session.persist( child );
+			session.persist( parent );
+		} );
+		scope.inTransaction( session -> {
+			final Person parent = session.find( Person.class, 2L );
+			assertThat( parent.getChild() ).isNotNull().extracting( Person::getId ).isEqualTo( 1L );
+		} );
+	}
+
+	@AfterAll
+	public void tearDown(SessionFactoryScope scope) {
+		scope.getSessionFactory().getSchemaManager().truncateMappedObjects();
+	}
+
+	@Entity( name = "Person" )
+	static class Person {
+		@Id
+		private Long id;
+
+		@OneToOne( fetch = FetchType.LAZY )
+		@JoinTable(
+				name = "Parent_Child",
+				joinColumns = @JoinColumn( name = "parent_id", referencedColumnName = "id" ),
+				inverseJoinColumns = @JoinColumn( name = "child_id", referencedColumnName = "id" )
+		)
+		private Person child;
+
+		@OneToOne( mappedBy = "child", fetch = FetchType.LAZY )
+		private Person parent;
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+
+		public Person getChild() {
+			return child;
+		}
+
+		public void setChild(Person child) {
+			this.child = child;
+		}
+
+		public Person getParent() {
+			return parent;
+		}
+	}
+}