From 4dfac9ce2d8abc045e78abd3cbcd783120f91a60 Mon Sep 17 00:00:00 2001
From: Marco Belladelli <marco@hibernate.org>
Date: Tue, 14 Feb 2023 10:59:26 +0100
Subject: [PATCH] HHH-16080 Add test for issue

---
 .../onetoone/OneToOneIsNullQueryTest.java     | 113 ++++++++++++++++++
 1 file changed, 113 insertions(+)
 create mode 100644 hibernate-core/src/test/java/org/hibernate/orm/test/mapping/onetoone/OneToOneIsNullQueryTest.java

diff --git a/hibernate-core/src/test/java/org/hibernate/orm/test/mapping/onetoone/OneToOneIsNullQueryTest.java b/hibernate-core/src/test/java/org/hibernate/orm/test/mapping/onetoone/OneToOneIsNullQueryTest.java
new file mode 100644
index 0000000000..00edf775ea
--- /dev/null
+++ b/hibernate-core/src/test/java/org/hibernate/orm/test/mapping/onetoone/OneToOneIsNullQueryTest.java
@@ -0,0 +1,113 @@
+/*
+ * 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.JiraKey;
+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.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.OneToOne;
+import jakarta.persistence.TypedQuery;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Marco Belladelli
+ */
+@SessionFactory
+@DomainModel(annotatedClasses = {
+		OneToOneIsNullQueryTest.Thing.class,
+		OneToOneIsNullQueryTest.ThingStats.class
+})
+@JiraKey("HHH-16080")
+public class OneToOneIsNullQueryTest {
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Thing thing1 = new Thing( 1L );
+			final ThingStats stats = new ThingStats( thing1.getPk(), 10 );
+			thing1.setThingStats( stats );
+			final Thing thing2 = new Thing( 2L );
+			session.persist( thing1 );
+			session.persist( thing2 );
+			session.persist( stats );
+		} );
+	}
+
+	@Test
+	public void testIsNullQuery(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			String ql = "select thing from Thing thing"
+					+ " left join thing.thingStats thingStats "
+					+ " where thingStats is null or thingStats.countRejected = 0";
+			TypedQuery<Thing> q = session.createQuery( ql, Thing.class );
+			assertThat( q.getSingleResult().getPk() ).isEqualTo( 2L );
+		} );
+	}
+
+	@Entity(name = "Thing")
+	public static class Thing {
+		@Id
+		@Column(name = "thing_pk")
+		private Long pk;
+
+		@OneToOne
+		@JoinColumn(name = "thing_pk")
+		private ThingStats thingStats;
+
+		public Thing() {
+		}
+
+		public Thing(Long pk) {
+			this.pk = pk;
+		}
+
+		public Long getPk() {
+			return pk;
+		}
+
+		public ThingStats getThingStats() {
+			return thingStats;
+		}
+
+		public void setThingStats(ThingStats thingStats) {
+			this.thingStats = thingStats;
+		}
+	}
+
+	@Entity(name = "ThingStats")
+	public static class ThingStats {
+		@Id
+		@Column(name = "thing_fk", nullable = false)
+		private Long thingPk;
+
+		private Integer countRejected;
+
+		public ThingStats() {
+		}
+
+		public ThingStats(Long thingPk, Integer countRejected) {
+			this.thingPk = thingPk;
+			this.countRejected = countRejected;
+		}
+
+		public Long getThingPk() {
+			return thingPk;
+		}
+
+		public Integer getCountRejected() {
+			return countRejected;
+		}
+	}
+}