HHH-17075 Reproducer for lazy loading of association with non-PK referencedColumnName yielding null

hibernate-core/src/test/java/org/hibernate/orm/test/bytecode/enhancement/lazy/LazyToOneJoinOnNonPrimaryKeyColumnTest.java

@@ -0,0 +1,140 @@
+/*
+ * 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.bytecode.enhancement.lazy;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.bytecode.enhancement.EnhancementOptions;
+import org.hibernate.testing.junit4.BaseNonConfigCoreFunctionalTestCase;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+
+@RunWith(BytecodeEnhancerRunner.class)
+@EnhancementOptions(lazyLoading = true)
+@JiraKey("HHH-17075")
+public class LazyToOneJoinOnNonPrimaryKeyColumnTest extends BaseNonConfigCoreFunctionalTestCase {
+
+	@Override
+	public Class<?>[] getAnnotatedClasses() {
+		return new Class<?>[] { EntityA.class, EntityB.class };
+	}
+
+	@Before
+	public void prepare() {
+		inTransaction( s -> {
+			EntityA entityA = new EntityA( 1 );
+			entityA.setMyUniqueKey( "someValue" );
+			s.persist( entityA );
+			EntityB entityB = new EntityB( 2 );
+			entityB.setMyAssociation( entityA );
+			s.persist( entityB );
+
+			EntityB entityB2 = new EntityB( 3 );
+			s.persist( entityB2 );
+		} );
+	}
+
+	@After
+	public void tearDown() {
+		inTransaction( s -> {
+			s.createMutationQuery( "delete entityb" ).executeUpdate();
+			s.createMutationQuery( "delete entitya" ).executeUpdate();
+		} );
+	}
+
+	@Test
+	public void testLazyLoading() {
+		inTransaction( s -> {
+			EntityB entityB = s.get( EntityB.class, 2 );
+			// Trigger lazy loading
+			assertThat( entityB.getMyAssociation() )
+					.isNotNull() // When the bug isn't fixed, this assertion fails
+					.returns( 1, EntityA::getId );
+
+			entityB = s.get( EntityB.class, 3 );
+			assertThat( entityB.getMyAssociation() )
+					.isNull();
+		} );
+	}
+
+	@Entity(name = "entitya")
+	public static class EntityA {
+
+		@Id
+		private Integer id;
+
+		@Column(unique = true)
+		private String myUniqueKey;
+
+		protected EntityA() {
+		}
+
+		public EntityA(Integer id) {
+			this.id = id;
+		}
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public String getMyUniqueKey() {
+			return myUniqueKey;
+		}
+
+		public void setMyUniqueKey(String myUniqueKey) {
+			this.myUniqueKey = myUniqueKey;
+		}
+	}
+
+	@Entity(name = "entityb")
+	public static class EntityB {
+		@Id
+		private Integer id;
+
+		@ManyToOne(fetch = FetchType.LAZY)
+		@JoinColumn(name = "myForeignKey", referencedColumnName = "myUniqueKey")
+		private EntityA myAssociation;
+
+		protected EntityB() {
+		}
+
+		public EntityB(Integer id) {
+			this.id = id;
+		}
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public EntityA getMyAssociation() {
+			return myAssociation;
+		}
+
+		public void setMyAssociation(EntityA myAssociation) {
+			this.myAssociation = myAssociation;
+		}
+	}
+}