DataCmns511Tests.java

/*
 * Copyright 2014-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.data.util;

import static org.assertj.core.api.Assertions.*;

import java.util.HashSet;
import java.util.Optional;
import java.util.Set;

import org.assertj.core.api.OptionalAssert;
import org.junit.Test;

/**
 * Unit tests to reproduce issues reported in DATACMNS-511.
 * 
 * @author Oliver Gierke
 */
public class DataCmns511Tests {

	@Test // DATACMNS-511
	public void detectsEqualTypeVariableTypeInformationInstances() {

		OptionalAssert<TypeInformation<?>> assertion = assertThat(
				ClassTypeInformation.from(AbstractRole.class).getProperty("createdBy"));

		assertion.flatMap(it -> it.getProperty("roles"))//
				.map(TypeInformation::getActualType)//
				.flatMap(it -> it.getProperty("createdBy"))//
				.hasValueSatisfying(second -> {

					Optional<TypeInformation<?>> third = second.getProperty("roles")//
							.map(TypeInformation::getActualType)//
							.flatMap(it -> it.getProperty("createdBy"));

					assertThat(third).hasValue(second);
					assertThat(third).map(Object::hashCode).hasValue(second.hashCode());
				});
	}

	static class AbstractRole<USER extends AbstractUser<USER, ROLE>, ROLE extends AbstractRole<USER, ROLE>>
			extends AuditingEntity<USER> {

		String name;
	}

	static abstract class AbstractUser<USER extends AbstractUser<USER, ROLE>, ROLE extends AbstractRole<USER, ROLE>> {

		Set<ROLE> roles = new HashSet<>();
	}

	static abstract class AuditingEntity<USER extends AbstractUser<USER, ?>> {

		USER createdBy;
		USER lastModifiedBy;
	}
}