HHH-3354 Test auto flush remove previously added entity from collection

hibernate-core/src/test/java/org/hibernate/orm/test/flush/AutoFlushRemoveTest.java

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+/*
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.flush;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.Table;
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.Jira;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SessionFactory
+@DomainModel( annotatedClasses = {
+		AutoFlushRemoveTest.Item.class,
+		AutoFlushRemoveTest.Comment.class,
+} )
+@Jira( "https://hibernate.atlassian.net/browse/HHH-3354" )
+public class AutoFlushRemoveTest {
+	@BeforeAll
+	public void setUp(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Item first = new Item( 1L, "item" );
+			session.persist( first );
+		} );
+	}
+
+	@AfterAll
+	public void tearDown(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			session.createMutationQuery( "delete from Comment" ).executeUpdate();
+			session.createMutationQuery( "delete from Item" ).executeUpdate();
+		} );
+	}
+
+	@Test
+	public void test(SessionFactoryScope scope) {
+		scope.inTransaction( session -> {
+			final Item item = session.find( Item.class, 1L );
+
+			final Comment comment1 = new Comment( "c1", item );
+			session.persist( comment1 );
+			final Comment comment2 = new Comment( "c2", item );
+			session.persist( comment2 );
+			item.getComments().add( comment1 );
+			item.getComments().add( comment2 );
+
+			session.flush();
+
+			session.remove( comment1 );
+			comment1.item = null;
+		} );
+		scope.inTransaction( session -> {
+			final Item item = session.find( Item.class, 1L );
+			assertThat( item.getComments().size() ).isEqualTo( 1 );
+		});
+	}
+
+	@Entity( name = "Item" )
+	public static class Item {
+		@Id
+		private Long id;
+		private String name;
+		@OneToMany(mappedBy = "item")
+		private Set<Comment> comments = new HashSet<>();
+
+		public Item() {
+		}
+
+		public Item(Long id, String name) {
+			this.id = id;
+			this.name = name;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public Set<Comment> getComments() {
+			return comments;
+		}
+	}
+
+	@Entity( name = "Comment" )
+	@Table(name = "item_comment")
+	public static class Comment {
+		@Id
+		@GeneratedValue
+		private Long id;
+		private String text;
+		@ManyToOne(fetch = FetchType.LAZY)
+		private Item item;
+
+		public Comment() {
+		}
+
+		public Comment(String text, Item item) {
+			this.text = text;
+			this.item = item;
+		}
+
+		public String getText() {
+			return text;
+		}
+
+		public Item getItem() {
+			return item;
+		}
+	}
+}