From 9952c0984354a45e293213ae3257071dd5eca3fd Mon Sep 17 00:00:00 2001
From: Steve Ebersole <steve@hibernate.org>
Date: Wed, 10 Mar 2021 16:23:42 -0600
Subject: [PATCH] HHH-14491 - Apply default allocation/increment size for
 @GeneratedValue(AUTO) HHH-14492 - Prefer sequence-per-entity (hierarchy) for
 @GeneratedValue(AUTO) by default

- added test as @FailureExpected to track this into 6.0
---
 .../enhanced/auto/NewGeneratorsTests.java     | 88 +++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 hibernate-core/src/test/java/org/hibernate/test/idgen/enhanced/auto/NewGeneratorsTests.java

diff --git a/hibernate-core/src/test/java/org/hibernate/test/idgen/enhanced/auto/NewGeneratorsTests.java b/hibernate-core/src/test/java/org/hibernate/test/idgen/enhanced/auto/NewGeneratorsTests.java
new file mode 100644
index 0000000000..5d73e16074
--- /dev/null
+++ b/hibernate-core/src/test/java/org/hibernate/test/idgen/enhanced/auto/NewGeneratorsTests.java
@@ -0,0 +1,88 @@
+/*
+ * 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.idgen.enhanced.auto;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.AvailableSettings;
+import org.hibernate.dialect.H2Dialect;
+import org.hibernate.id.enhanced.DatabaseStructure;
+import org.hibernate.id.enhanced.SequenceStyleGenerator;
+import org.hibernate.id.factory.internal.DefaultIdentifierGeneratorFactory;
+import org.hibernate.mapping.PersistentClass;
+import org.hibernate.service.spi.ServiceRegistryImplementor;
+import org.hibernate.tool.schema.Action;
+
+import org.hibernate.testing.FailureExpected;
+import org.hibernate.testing.junit4.BaseUnitTestCase;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author Steve Ebersole
+ */
+public class NewGeneratorsTests extends BaseUnitTestCase {
+	@Test
+	@FailureExpected(
+			jiraKey = "HHH-14491",
+			message = "To be implemented for 6; see https://github.com/hibernate/hibernate-orm/discussions/3809"
+	)
+	public void testAutoDefaults() {
+		// check that `@GeneratedValue(AUTO)` with no explicit generator applies
+		// various defaults:
+		// 		- allocation/increment size = 50
+		//		- sequence-per-entity with a suffix
+
+		final StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder();
+		ssrb.applySetting( AvailableSettings.HBM2DDL_AUTO, Action.CREATE_DROP );
+
+		final StandardServiceRegistry ssr = ssrb.build();
+		final Metadata metadata = new MetadataSources( ssr )
+				.addAnnotatedClass( Entity1.class )
+				.buildMetadata();
+
+		final DefaultIdentifierGeneratorFactory generatorFactory = new DefaultIdentifierGeneratorFactory();
+		generatorFactory.injectServices( (ServiceRegistryImplementor) ssr );
+
+		final PersistentClass entityBinding = metadata.getEntityBinding( Entity1.class.getName() );
+		final SequenceStyleGenerator generator = (SequenceStyleGenerator) entityBinding.getRootClass().getIdentifier().createIdentifierGenerator(
+				generatorFactory,
+				new H2Dialect(),
+				"",
+				"",
+				entityBinding.getRootClass()
+		);
+
+		final DatabaseStructure databaseStructure = generator.getDatabaseStructure();
+
+		// HHH-14491 - what we want to happen
+		assertThat( databaseStructure.getName(), is( "Entity1_SEQ" ) );
+		// or this depending on the discussion (Jira) about using entity name v. table name as the base
+		assertThat( databaseStructure.getName(), is( "tbl_1_SEQ" ) );
+
+		// HHH-14491 - this is what we want to have happen
+		assertThat( databaseStructure.getIncrementSize(), is( 50 ) );
+	}
+
+	@Entity( name = "Entity1" )
+	@Table( name = "tbl_1" )
+	public static class Entity1 {
+		@Id
+		@GeneratedValue( strategy = GenerationType.AUTO )
+		private Integer id;
+	}
+}