HHH-19535 add test for Interceptor.postMerge()

Author: gavinking

hibernate-core/src/test/java/org/hibernate/orm/test/interceptor/merge/MergeAuditingInterceptor.java

@@ -0,0 +1,25 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.interceptor.merge;
+
+import org.hibernate.Interceptor;
+import org.hibernate.type.Type;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class MergeAuditingInterceptor implements Interceptor {
+
+	static final List<String> auditTrail = new ArrayList<>();
+
+	@Override
+	public void postMerge(Object source, Object target, Object id, Object[] targetState, Object[] originalState, String[] propertyNames, Type[] propertyTypes) {
+		for ( int i = 0; i < propertyNames.length; i++ ) {
+			if ( !propertyTypes[i].isEqual( originalState[i], targetState[i] ) ) {
+				auditTrail.add( propertyNames[i] + " changed from " + originalState[i] + " to " + targetState[i] + " for " + id );
+			}
+		}
+	}
+}

hibernate-core/src/test/java/org/hibernate/orm/test/interceptor/merge/MergeAuditingInterceptorTest.java

@@ -0,0 +1,46 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.interceptor.merge;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import org.hibernate.cfg.SessionEventSettings;
+import org.hibernate.testing.orm.junit.EntityManagerFactoryScope;
+import org.hibernate.testing.orm.junit.Jpa;
+import org.hibernate.testing.orm.junit.Setting;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+@Jpa(annotatedClasses = MergeAuditingInterceptorTest.Thing.class,
+		integrationSettings = @Setting(name = SessionEventSettings.INTERCEPTOR,
+				value = "org.hibernate.orm.test.interceptor.merge.MergeAuditingInterceptor"))
+class MergeAuditingInterceptorTest {
+	@Test
+	void test(EntityManagerFactoryScope scope) {
+		Thing t = scope.fromTransaction( em -> {
+			Thing thing = new Thing();
+			thing.name = "Hibernate";
+			em.persist( thing );
+			return thing;
+		} );
+		scope.inTransaction( em -> {
+			t.name = "Hibernate ORM";
+			Thing thing = em.merge( t );
+			assertEquals( 1, MergeAuditingInterceptor.auditTrail.size() );
+			assertEquals( "name changed from Hibernate to Hibernate ORM for " + t.id,
+					MergeAuditingInterceptor.auditTrail.get( 0 ) );
+		} );
+	}
+
+	@Entity
+	static class Thing {
+		@Id
+		@GeneratedValue
+		private Long id;
+		private String name;
+	}
+}