From f49b87600ef0e5869d7d7d3d54bc8e72953737a7 Mon Sep 17 00:00:00 2001
From: Marco Belladelli <marco@hibernate.org>
Date: Mon, 7 Aug 2023 10:01:01 +0200
Subject: [PATCH] HHH-16928 Add test for issue

---
 ...ElementCollectionLeftJoinSubqueryTest.java | 168 ++++++++++++++++++
 1 file changed, 168 insertions(+)
 create mode 100644 hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ElementCollectionLeftJoinSubqueryTest.java

diff --git a/hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ElementCollectionLeftJoinSubqueryTest.java b/hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ElementCollectionLeftJoinSubqueryTest.java
new file mode 100644
index 0000000000..0bec63ef04
--- /dev/null
+++ b/hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ElementCollectionLeftJoinSubqueryTest.java
@@ -0,0 +1,168 @@
+/*
+ * 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.query.hql;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+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.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.CollectionTable;
+import jakarta.persistence.ElementCollection;
+import jakarta.persistence.Embeddable;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.Tuple;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Marco Belladelli
+ */
+@DomainModel( annotatedClasses = {
+		ElementCollectionLeftJoinSubqueryTest.EntityA.class,
+		ElementCollectionLeftJoinSubqueryTest.EntityB.class,
+		ElementCollectionLeftJoinSubqueryTest.EmbeddableC.class
+} )
+@SessionFactory
+@Jira( "https://hibernate.atlassian.net/browse/HHH-16928" )
+public class ElementCollectionLeftJoinSubqueryTest {
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			var b = new EntityB();
+			b.getcCollection().add( new EmbeddableC( 1, "embeddable_1" ) );
+			b.getcCollection().add( new EmbeddableC( 2, "embeddable_2" ) );
+			session.persist( b );
+			var a = new EntityA();
+			a.getbCollection().add( b );
+			session.persist( a );
+		} );
+	}
+
+	@AfterAll
+	public void tearDown(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			session.createMutationQuery( "delete from EntityB" ).executeUpdate();
+			session.createMutationQuery( "delete from EntityA" ).executeUpdate();
+		} );
+	}
+
+	@Test
+	public void testNestedJoin(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final List<Tuple> resultList = session.createQuery(
+					"select a.id, b.id, c.intValue" +
+							" from EntityA a" +
+							" left join EntityB b on b.a.id = a.id" +
+							" left join b.cCollection as c" +
+							" where (c.intValue = (select max(c2.intValue)" +
+							" from b.cCollection as c2) or c.intValue is null)",
+					Tuple.class
+			).getResultList();
+			assertThat( resultList ).hasSize( 1 );
+			assertThat( resultList.get( 0 ).get( 2, Integer.class ) ).isEqualTo( 2 );
+		} );
+	}
+
+	@Test
+	public void testJoin(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final List<Tuple> resultList = session.createQuery(
+					"select b.id, c.intValue" +
+							" from EntityB b" +
+							" left join b.cCollection as c" +
+							" where (c.intValue = (select max(c2.intValue)" +
+							" from b.cCollection as c2) or c.intValue is null)",
+					Tuple.class
+			).getResultList();
+			assertThat( resultList ).hasSize( 1 );
+			assertThat( resultList.get( 0 ).get( 1, Integer.class ) ).isEqualTo( 2 );
+		} );
+	}
+
+	@Entity( name = "EntityA" )
+	public static class EntityA {
+		@Id
+		@GeneratedValue
+		private Integer id;
+
+		@OneToMany
+		@JoinColumn( name = "a_id" )
+		private List<EntityB> bCollection = new ArrayList<>();
+
+		public Integer getId() {
+			return id;
+		}
+
+		public List<EntityB> getbCollection() {
+			return bCollection;
+		}
+	}
+
+	@Entity( name = "EntityB" )
+	public static class EntityB {
+		@Id
+		@GeneratedValue
+		private Integer id;
+
+		@ManyToOne
+		@JoinColumn( name = "a_id" )
+		private EntityA a;
+
+		@ElementCollection
+		@CollectionTable( name = "c_embeddables", joinColumns = { @JoinColumn( name = "id" ) } )
+		private final Set<EmbeddableC> cCollection = new HashSet<>();
+
+		public EntityA getA() {
+			return a;
+		}
+
+		public void setA(EntityA a) {
+			this.a = a;
+		}
+
+		public Set<EmbeddableC> getcCollection() {
+			return cCollection;
+		}
+	}
+
+	@Embeddable
+	public static class EmbeddableC {
+		private Integer intValue;
+
+		private String name;
+
+		public EmbeddableC() {
+		}
+
+		public EmbeddableC(Integer intValue, String name) {
+			this.intValue = intValue;
+			this.name = name;
+		}
+
+		public Integer getIntValue() {
+			return intValue;
+		}
+
+		public String getName() {
+			return name;
+		}
+	}
+}