HHH-10463 - coalesce with null values and PostgreSQL throws exception

hibernate-core/src/test/java/org/hibernate/test/hql/CoalesceTest.java

@@ -0,0 +1,141 @@
+/*
+ * 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.test.hql;
+
+import java.util.List;
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import org.hibernate.dialect.PostgreSQL81Dialect;
+import org.hibernate.query.Query;
+
+import org.hibernate.testing.RequiresDialect;
+import org.hibernate.testing.SkipForDialect;
+import org.hibernate.testing.TestForIssue;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.hasItem;
+import static org.hibernate.testing.transaction.TransactionUtil.doInHibernate;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author Johannes Buehler
+ */
+@TestForIssue( jiraKey = "HHH-10463")
+public class CoalesceTest extends BaseCoreFunctionalTestCase {
+
+    private Person person;
+
+    @Override
+    protected Class[] getAnnotatedClasses() {
+        return new Class[] {
+                Person.class
+        };
+    }
+
+    @Before
+    public void setUp() {
+        doInHibernate( this::sessionFactory, session -> {
+            person = new Person();
+            person.setName("Johannes");
+            person.setSurname("Buehler");
+            session.persist(person);
+        } );
+    }
+
+    @Test
+    public void HHH_10463_TestCoalesce() {
+        doInHibernate( this::sessionFactory, session -> {
+            Query query = session.createQuery( "from Person p where p.name = coalesce(:name , p.name) ");
+            query.setParameter("name", "Johannes");
+            List<Person> resultList = query.getResultList();
+            assertThat(resultList, hasItem(person));
+        } );
+
+    }
+    
+    @Test
+    @SkipForDialect( jiraKey = "HHH-10463", value =  PostgreSQL81Dialect.class)
+    public void HHH_10463_NullInCoalesce() {
+        doInHibernate( this::sessionFactory, session -> {
+            Query query = session.createQuery("from Person p where p.name = coalesce(:name, p.name) ");
+            query.setParameter("name", null);
+            List<Person> resultList = query.getResultList();
+            assertThat(resultList, hasItem(person));
+        } );
+    }
+
+    @Test
+    @RequiresDialect( PostgreSQL81Dialect.class )
+    public void HHH_10463_NullInCoalesce_PostgreSQL_Workaround() {
+        doInHibernate( this::sessionFactory, session -> {
+            Query query = session.createQuery("from Person p where p.name = coalesce(cast( :name as string) , p.name) ");
+            query.setParameter("name", null);
+            List<Person> resultList = query.getResultList();
+            assertThat(resultList, hasItem(person));
+        } );
+    }
+    
+    @Entity(name = "Person")
+    public static class Person {
+
+        @Id
+        @GeneratedValue
+        private Integer id;
+
+        @Column
+        private String name;
+
+        @Column
+        private String surname;
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public String getSurname() {
+            return surname;
+        }
+
+        public void setSurname(String surname) {
+            this.surname = surname;
+        }
+
+        public Integer getId() {
+            return id;
+        }
+
+        public void setId(Integer id) {
+            this.id = id;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (!(o instanceof Person )) return false;
+
+            Person person = (Person) o;
+
+            return id != null ? id.equals(person.id) : person.id == null;
+
+        }
+
+        @Override
+        public int hashCode() {
+            return id != null ? id.hashCode() : 0;
+        }
+    }
+
+}