Fix EnhancedProxy with Embeddable and Lazy BasicAttribute

hibernate-core/src/main/java/org/hibernate/metamodel/mapping/internal/MappingModelCreationHelper.java

@@ -53,6 +53,7 @@ import org.hibernate.metamodel.mapping.CollectionIdentifierDescriptor;
 import org.hibernate.metamodel.mapping.CollectionMappingType;
 import org.hibernate.metamodel.mapping.CollectionPart;
 import org.hibernate.metamodel.mapping.CompositeIdentifierMapping;
+import org.hibernate.metamodel.mapping.EmbeddableMappingType;
 import org.hibernate.metamodel.mapping.EmbeddableValuedModelPart;
 import org.hibernate.metamodel.mapping.EntityIdentifierMapping;
 import org.hibernate.metamodel.mapping.EntityMappingType;
@@ -232,8 +233,16 @@ public class MappingModelCreationHelper {
 			}
 		};
 
-		final FetchTiming fetchTiming = bootProperty.isLazy() ? FetchTiming.DELAYED : FetchTiming.IMMEDIATE;
-		final FetchStyle fetchStyle = bootProperty.isLazy() ? FetchStyle.SELECT : FetchStyle.JOIN;
+		final FetchTiming fetchTiming;
+		final FetchStyle fetchStyle;
+		if ( declaringType instanceof EmbeddableMappingType ) {
+			fetchTiming = FetchTiming.IMMEDIATE;
+			fetchStyle = FetchStyle.JOIN;
+		}
+		else {
+			fetchTiming = bootProperty.isLazy() ? FetchTiming.DELAYED : FetchTiming.IMMEDIATE;
+			fetchStyle = bootProperty.isLazy() ? FetchStyle.SELECT : FetchStyle.JOIN;
+		}
 		final ValueGeneration valueGeneration = bootProperty.getValueGenerationStrategy();
 
 		if ( valueConverter != null ) {

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/inheritance/BaseIdEntityByteCodeTest.java

@@ -0,0 +1,122 @@
+/*
+ * Hibernate Search, full-text search for your domain model
+ *
+ * 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.orm.test.mapping.inheritance;
+
+import org.hibernate.annotations.LazyGroup;
+
+import org.hibernate.testing.bytecode.enhancement.BytecodeEnhancerRunner;
+import org.hibernate.testing.junit4.BaseCoreFunctionalTestCase;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import jakarta.persistence.Basic;
+import jakarta.persistence.Embeddable;
+import jakarta.persistence.Embedded;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.Id;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(BytecodeEnhancerRunner.class)
+public class BaseIdEntityByteCodeTest extends BaseCoreFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class[] { BaseEntity.class, ContainingEntity.class };
+	}
+
+	@Test
+	public void test() {
+		inTransaction( session -> {
+			ContainingEntity entity1 = new ContainingEntity();
+			entity1.id = 1;
+			entity1.baseText = "initialValue";
+
+			ContainedEmbeddable containedEmbeddable = new ContainedEmbeddable();
+			entity1.containedEmbeddable = containedEmbeddable;
+			containedEmbeddable.text = "initialValue";
+			session.persist( entity1 );
+		} );
+
+		inTransaction( session -> {
+			ContainingEntity entity = session.load( ContainingEntity.class, 1 );
+			ContainedEmbeddable containedEmbeddable = entity.getContainedEmbeddable();
+			assertThat( containedEmbeddable.getText() ).isEqualTo( "initialValue" );
+		} );
+	}
+
+	@Entity(name = "base")
+	public static class BaseEntity {
+
+		@Id
+		public Integer id;
+
+		@Basic(fetch = FetchType.LAZY)
+		@LazyGroup("base")
+		public String baseText;
+
+		public String baseText2;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public String getBaseText() {
+			return baseText;
+		}
+
+		public void setBaseText(String baseText) {
+			this.baseText = baseText;
+		}
+
+		public String getBaseText2() {
+			return baseText2;
+		}
+
+		public void setBaseText2(String baseText2) {
+			this.baseText2 = baseText2;
+		}
+
+
+	}
+
+	@Entity(name = "containing")
+	public static class ContainingEntity extends BaseEntity {
+		@Embedded
+		public ContainedEmbeddable containedEmbeddable;
+
+		public ContainedEmbeddable getContainedEmbeddable() {
+			return containedEmbeddable;
+		}
+
+		public void setContainedEmbeddable(ContainedEmbeddable containedEmbeddable) {
+			this.containedEmbeddable = containedEmbeddable;
+		}
+
+	}
+
+	@Embeddable
+	public static class ContainedEmbeddable {
+
+		@Basic(fetch = FetchType.LAZY)
+		public String text;
+
+		public String getText() {
+			return text;
+		}
+
+		public void setText(String text) {
+			this.text = text;
+		}
+	}
+
+}