HHH-13199 Add test case

hibernate-core/src/test/java/org/hibernate/jpa/test/criteria/simplecase/BasicSimpleCaseTest.java

@@ -6,6 +6,14 @@
  */
 package org.hibernate.jpa.test.criteria.simplecase;
 
+import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+import java.util.List;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EntityManager;
 import javax.persistence.GeneratedValue;
@@ -13,22 +21,15 @@ import javax.persistence.Id;
 import javax.persistence.Table;
 import javax.persistence.Tuple;
 import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaBuilder.SimpleCase;
 import javax.persistence.criteria.CriteriaQuery;
 import javax.persistence.criteria.Expression;
 import javax.persistence.criteria.Path;
 import javax.persistence.criteria.Root;
 
 import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
-
-import org.junit.Test;
-
 import org.hibernate.testing.TestForIssue;
-
-import static javax.persistence.criteria.CriteriaBuilder.SimpleCase;
-import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
-import static org.junit.Assert.assertEquals;
-
-import java.util.List;
+import org.junit.Test;
 
 /**
  * Mote that these are simply performing syntax checking (can the criteria query
@@ -40,7 +41,7 @@ public class BasicSimpleCaseTest extends BaseEntityManagerFunctionalTestCase {
 
 	@Override
 	protected Class<?>[] getAnnotatedClasses() {
-		return new Class[] {Customer.class};
+		return new Class[] {Customer.class, TestEntity.class};
 	}
 
 	@Test
@@ -209,6 +210,67 @@ public class BasicSimpleCaseTest extends BaseEntityManagerFunctionalTestCase {
 		assertEquals( EmailType.UNKNOWN, results.get( 2 ).get( 1 )  );
 	}
 
+	@Test
+	@TestForIssue(jiraKey = "HHH-13199")
+	public void testCaseEnumInSum() throws Exception {
+		doInJPA( this::entityManagerFactory, em -> {
+			// create entities
+			TestEntity e1 = new TestEntity();
+			e1.setEnumField( TestEnum.VAL_1 );
+			e1.setValue( 20L );
+			em.persist( e1 );
+
+			TestEntity e2 = new TestEntity();
+			e2.setEnumField( TestEnum.VAL_2 );
+			e2.setValue( 10L );
+			em.persist( e2 );
+		} );
+
+		doInJPA( this::entityManagerFactory, em -> {
+			// Works in previous version (e.g. Hibernate 5.3.7.Final)
+			// Fails in Hibernate 5.4.0.Final
+			CriteriaBuilder cb = em.getCriteriaBuilder();
+			CriteriaQuery<Tuple> query = cb.createTupleQuery();
+			Root<TestEntity> r = query.from( TestEntity.class );
+
+			CriteriaBuilder.Case<Long> case1 = cb.selectCase();
+			case1.when( cb.equal( r.<TestEnum> get( "enumField" ), cb.literal( TestEnum.VAL_1 ) ),
+					r.<Long> get( "value" ) );
+			case1.otherwise( cb.nullLiteral( Long.class ) );
+
+			CriteriaBuilder.Case<Long> case2 = cb.selectCase();
+			case2.when( cb.equal( r.<TestEnum> get( "enumField" ), cb.literal( TestEnum.VAL_2 ) ),
+					r.<Long> get( "value" ) );
+			case2.otherwise( cb.nullLiteral( Long.class ) );
+
+			/*
+			 * Forces enums to be bound as parameters, so SQL is something like
+			 * "SELECT enumfield AS enumField, SUM(CASE WHEN enumfield = ? THEN value
+			 * ELSE NULL END) AS VAL_1, SUM(CASE WHEN enumfield =? THEN value ELSE NULL END) AS VAL_1 FROM TestEntity
+			 * GROUP BY enumfield"
+			 */
+			query
+					.select( cb.tuple( r.<TestEnum> get( "enumField" ).alias( "enumField" ),
+							cb.sum( case1 ).alias( "VAL_1" ),
+							cb.sum( case2 ).alias( "VAL_2" ) ) )
+					.groupBy( r.<TestEnum> get( "enumField" ) );
+
+			List<Tuple> list = em.createQuery( query ).getResultList();
+			assertEquals( 2, list.size() );
+			for ( Tuple tuple : list ) {
+				TestEnum enumVal = tuple.get( "enumField", TestEnum.class );
+				if ( enumVal == TestEnum.VAL_1 ) {
+					assertEquals( 20L, tuple.get( "VAL_1", Long.class ).longValue() );
+					assertNull( tuple.get( "VAL_2", Long.class ) );
+				}
+				else if ( enumVal == TestEnum.VAL_2 ) {
+					assertNull( tuple.get( "VAL_1", Long.class ) );
+					assertEquals( 10L, tuple.get( "VAL_2", Long.class ).longValue() );
+				}
+			}
+		} );
+	}
+
 	@Entity(name = "Customer")
 	@Table(name = "customer")
 	public static class Customer {
@@ -237,4 +299,72 @@ public class BasicSimpleCaseTest extends BaseEntityManagerFunctionalTestCase {
 	public enum EmailType {
 		LONG, NORMAL, UNKNOWN
 	}
+
+	@Entity(name = "TestEntity")
+	public static class TestEntity {
+		@Id
+		@GeneratedValue
+		private long id;
+
+		@Convert(converter = TestEnumConverter.class)
+		private TestEnum enumField;
+
+		private Long value;
+
+		public long getId() {
+			return id;
+		}
+
+		public TestEnum getEnumField() {
+			return enumField;
+		}
+
+		public void setEnumField(TestEnum enumField) {
+			this.enumField = enumField;
+		}
+
+		public Long getValue() {
+			return value;
+		}
+
+		public void setValue(Long value) {
+			this.value = value;
+		}
+	}
+
+	public static enum TestEnum {
+		VAL_1("1"),
+		VAL_2("2");
+
+		private final String value;
+
+		private TestEnum(String value) {
+			this.value = value;
+		}
+
+		public String getValue() {
+			return value;
+		}
+
+		public static TestEnum fromValue(String value) {
+			if (value.equals(VAL_1.value)) {
+				return VAL_1;
+			} else if (value.equals(VAL_2.value)) {
+				return VAL_2;
+			}
+			return null;
+		}
+	}
+
+	public static class TestEnumConverter implements AttributeConverter<TestEnum, String> {
+		@Override
+		public String convertToDatabaseColumn(TestEnum attribute) {
+			return attribute == null ? null : attribute.getValue();
+		}
+
+		@Override
+		public TestEnum convertToEntityAttribute(String dbData) {
+			return dbData == null ? null : TestEnum.fromValue(dbData);
+		}
+	}
 }