HHH-11500 - Provide the cause of the error when validating @Loader named queries

hibernate-core/src/main/java/org/hibernate/internal/SessionFactoryImpl.java

@@ -320,11 +320,16 @@ public final class SessionFactoryImpl implements SessionFactoryImplementor {
 				final Map<String, HibernateException> errors = checkNamedQueries();
 				if ( !errors.isEmpty() ) {
 					StringBuilder failingQueries = new StringBuilder( "Errors in named queries: " );
-					String sep = "";
+					String separator = System.lineSeparator();
+
 					for ( Map.Entry<String, HibernateException> entry : errors.entrySet() ) {
 						LOG.namedQueryError( entry.getKey(), entry.getValue() );
-						failingQueries.append( sep ).append( entry.getKey() );
-						sep = ", ";
+
+						failingQueries
+							.append( separator)
+							.append( entry.getKey() )
+							.append( " failed because of: " )
+							.append( entry.getValue() );
 					}
 					throw new HibernateException( failingQueries.toString() );
 				}

hibernate-core/src/test/java/org/hibernate/test/annotations/loader/LoaderWithInvalidQueryTest.java

@@ -0,0 +1,95 @@
+/*
+ * 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.annotations.loader;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+
+import org.hibernate.HibernateException;
+import org.hibernate.annotations.Loader;
+import org.hibernate.annotations.NamedNativeQueries;
+import org.hibernate.annotations.NamedQuery;
+import org.hibernate.jpa.test.BaseEntityManagerFunctionalTestCase;
+
+import org.hibernate.testing.util.ExceptionUtil;
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author Vlad Mihalcea
+ */
+public class LoaderWithInvalidQueryTest extends BaseEntityManagerFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class<?>[] {
+			Person.class
+		};
+	}
+
+	@Override
+	public void buildEntityManagerFactory() throws Exception {
+		try {
+			super.buildEntityManagerFactory();
+		}
+		catch (Exception expected) {
+			HibernateException rootCause = (HibernateException) ExceptionUtil.rootCause( expected );
+			assertTrue(rootCause.getMessage().contains( "could not resolve property: valid" ));
+			assertTrue(rootCause.getMessage().contains( "_Person is not mapped" ));
+		}
+	}
+
+	@Test
+	public void test() {
+	}
+
+
+	@Entity(name = "Person")
+	@Loader(namedQuery = "invalid_sql")
+	@NamedQuery(
+		name = "invalid_sql",
+		query = "SELECT p " +
+				"FROM Person p " +
+				"WHERE p.id = ? and p.valid = true"
+	)
+	@NamedQuery(
+		name = "another_invalid_sql",
+		query = "SELECT p " +
+				"FROM _Person p " +
+				"WHERE p.id = ?"
+	)
+	public static class Person {
+
+		@Id
+		@GeneratedValue
+		private Long id;
+
+		@Column(name = "full_name")
+		private String name;
+
+		public Long getId() {
+			return id;
+		}
+
+		public void setId(Long id) {
+			this.id = id;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public void setName(String name) {
+			this.name = name;
+		}
+	}
+	//end::sql-custom-crud-example[]
+
+}