HHH-19905 Add test for issue

Author: mbellade

hibernate-core/src/test/java/org/hibernate/orm/test/query/hql/ImplicitNestedJoinTest.java

@@ -0,0 +1,141 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.query.hql;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+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 static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Christian Beikov
+ */
+@DomainModel(annotatedClasses = {
+		ImplicitNestedJoinTest.RootEntity.class,
+		ImplicitNestedJoinTest.FirstLevelReferencedEntity.class,
+		ImplicitNestedJoinTest.SecondLevelReferencedEntityA.class,
+		ImplicitNestedJoinTest.SecondLevelReferencedEntityB.class
+})
+@SessionFactory
+@Jira("https://hibernate.atlassian.net/browse/HHH-19905")
+public class ImplicitNestedJoinTest {
+
+	@Test
+	public void testInnerAndLeftJoin(SessionFactoryScope scope) {
+		scope.inSession( session -> {
+			final var resultList = session.createQuery(
+					"select r.id from RootEntity r"
+					+ " join r.firstLevelReference.secondLevelReferenceA sa "
+					+ " left join r.firstLevelReference.secondLevelReferenceB sb",
+					Long.class
+			).getResultList();
+			assertThat( resultList ).hasSize( 2 ).containsExactlyInAnyOrder( 1L, 2L );
+		} );
+	}
+
+	@Test
+	public void testLeftAndInnerJoin(SessionFactoryScope scope) {
+		scope.inSession( session -> {
+			final var resultList = session.createQuery(
+					"select r.id from RootEntity r"
+					+ " left join r.firstLevelReference.secondLevelReferenceA sa "
+					+ " join r.firstLevelReference.secondLevelReferenceB sb",
+					Long.class
+			).getResultList();
+			assertThat( resultList ).hasSize( 1 ).containsExactly( 1L );
+		} );
+	}
+
+	@Test
+	public void testBothInnerJoins(SessionFactoryScope scope) {
+		scope.inSession( session -> {
+			final var resultList = session.createQuery(
+					"select r.id from RootEntity r"
+					+ " join r.firstLevelReference.secondLevelReferenceA sa "
+					+ " join r.firstLevelReference.secondLevelReferenceB sb",
+					Long.class
+			).getResultList();
+			assertThat( resultList ).hasSize( 1 ).containsExactly( 1L );
+		} );
+	}
+
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			// create some test data : one first level reference with both second level references, and
+			// another first level reference with only one second level reference
+			SecondLevelReferencedEntityA secondLevelA = new SecondLevelReferencedEntityA();
+			secondLevelA.id = 1L;
+			secondLevelA.name = "Second Level A";
+			session.persist( secondLevelA );
+			SecondLevelReferencedEntityB secondLevelB = new SecondLevelReferencedEntityB();
+			secondLevelB.id = 1L;
+			session.persist( secondLevelB );
+			FirstLevelReferencedEntity firstLevel1 = new FirstLevelReferencedEntity();
+			firstLevel1.id = 1L;
+			firstLevel1.secondLevelReferenceA = secondLevelA;
+			firstLevel1.secondLevelReferenceB = secondLevelB;
+			session.persist( firstLevel1 );
+			RootEntity root1 = new RootEntity();
+			root1.id = 1L;
+			root1.firstLevelReference = firstLevel1;
+			session.persist( root1 );
+			FirstLevelReferencedEntity firstLevel2 = new FirstLevelReferencedEntity();
+			firstLevel2.id = 2L;
+			firstLevel2.secondLevelReferenceA = secondLevelA;
+			session.persist( firstLevel2 );
+			RootEntity root2 = new RootEntity();
+			root2.id = 2L;
+			root2.firstLevelReference = firstLevel2;
+			session.persist( root2 );
+		} );
+	}
+
+	@AfterAll
+	public void tearDown(SessionFactoryScope scope) {
+		scope.getSessionFactory().getSchemaManager().truncateMappedObjects();
+	}
+
+	@Entity(name = "RootEntity")
+	public static class RootEntity {
+		@Id
+		private Long id;
+
+		@ManyToOne
+		private FirstLevelReferencedEntity firstLevelReference;
+	}
+
+	@Entity(name = "FirstLevelReferencedEntity")
+	public static class FirstLevelReferencedEntity {
+		@Id
+		private Long id;
+		@ManyToOne
+		private SecondLevelReferencedEntityA secondLevelReferenceA;
+		@ManyToOne
+		private SecondLevelReferencedEntityB secondLevelReferenceB;
+
+	}
+
+	@Entity(name = "SecondLevelReferencedEntityA")
+	public static class SecondLevelReferencedEntityA {
+		@Id
+		private Long id;
+		private String name;
+	}
+
+	@Entity(name = "SecondLevelReferencedEntityB")
+	public static class SecondLevelReferencedEntityB {
+		@Id
+		private Long id;
+	}
+}