HHH-14977 - @Where is broken in 6.0

simple fix hooking in to the existing String based building. working on a version that
uses the AST

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

@@ -16,6 +16,7 @@
 
 import org.hibernate.Filter;
 import org.hibernate.MappingException;
+import org.hibernate.engine.spi.FilterDefinition;
 import org.hibernate.engine.spi.LoadQueryInfluencers;
 import org.hibernate.engine.spi.SessionFactoryImplementor;
 import org.hibernate.internal.util.StringHelper;
@@ -67,8 +68,9 @@ public FilterHelper(List<FilterConfiguration> filters, SessionFactoryImplementor
 			filterNames[filterCount] = safeInterning( filter.getName() );
 			filterConditions[filterCount] = safeInterning( filter.getCondition() );
 			filterAliasTableMaps[filterCount] = filter.getAliasTableMap( factory );
-			if ( ( filterAliasTableMaps[filterCount].isEmpty() || isTableFromPersistentClass( filterAliasTableMaps[filterCount] ) ) && filter
-					.useAutoAliasInjection() ) {
+			if ( ( filterAliasTableMaps[filterCount].isEmpty()
+					|| isTableFromPersistentClass( filterAliasTableMaps[filterCount] ) )
+					&& filter.useAutoAliasInjection() ) {
 				filterConditions[filterCount] = safeInterning(
 							Template.renderWhereStringTemplate(
 							filter.getCondition(),
@@ -79,6 +81,7 @@ public FilterHelper(List<FilterConfiguration> filters, SessionFactoryImplementor
 				);
 				filterAutoAliasFlags[filterCount] = true;
 			}
+
 			filterConditions[filterCount] = safeInterning(
 					StringHelper.replace(
 						filterConditions[filterCount],

hibernate-core/src/main/java/org/hibernate/persister/collection/OneToManyPersister.java

@@ -19,6 +19,7 @@
 import org.hibernate.engine.jdbc.batch.internal.BasicBatchKey;
 import org.hibernate.engine.spi.SharedSessionContractImplementor;
 import org.hibernate.internal.FilterAliasGenerator;
+import org.hibernate.internal.util.StringHelper;
 import org.hibernate.internal.util.collections.ArrayHelper;
 import org.hibernate.jdbc.Expectation;
 import org.hibernate.jdbc.Expectations;
@@ -497,7 +498,13 @@ public String filterFragment(String alias) throws MappingException {
 	protected String filterFragment(String alias, Set<String> treatAsDeclarations) throws MappingException {
 		String result = super.filterFragment( alias );
 		if ( getElementPersister() instanceof Joinable ) {
-			result += ( (Joinable) getElementPersister() ).oneToManyFilterFragment( alias, treatAsDeclarations );
+			final String associationFilter = ( (Joinable) getElementPersister() ).oneToManyFilterFragment( alias, treatAsDeclarations );
+			if ( StringHelper.isEmpty( result ) ) {
+				result = associationFilter;
+			}
+			else if ( StringHelper.isNotEmpty( associationFilter ) ) {
+				result += " and " + associationFilter;
+			}
 		}
 		return result;
 	}

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/where/DiscriminatorWhereTest.java

@@ -0,0 +1,134 @@
+/*
+ * 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.orm.test.mapping.where;
+
+import java.util.Set;
+
+import org.hibernate.annotations.Where;
+
+import org.hibernate.testing.orm.junit.DomainModel;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.SessionFactory;
+import org.hibernate.testing.orm.junit.SessionFactoryScope;
+import org.junit.jupiter.api.Test;
+
+import jakarta.persistence.DiscriminatorColumn;
+import jakarta.persistence.DiscriminatorType;
+import jakarta.persistence.DiscriminatorValue;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.Table;
+
+@DomainModel( annotatedClasses = {
+		DiscriminatorWhereTest.EntityA.class,
+		DiscriminatorWhereTest.EntityB.class,
+		DiscriminatorWhereTest.EntityC.class
+})
+@SessionFactory
+@JiraKey( "https://hibernate.atlassian.net/browse/HHH-14977" )
+public class DiscriminatorWhereTest {
+	@Test
+	public void testAddDiscriminatedEntityToCollectionWithWhere(SessionFactoryScope scope) {
+		// Initially save EntityA with an empty collection
+		final Integer id = scope.fromTransaction( (session) -> {
+			final EntityA entityA = new EntityA();
+			entityA.setName( "a" );
+			session.persist( entityA );
+			return entityA.getId();
+		} );
+
+		// Fetch EntityA and add a new EntityC to its collection.
+		// The collection is annotated with @Where("TYPE = 'C'")
+		scope.inTransaction( (session) -> {
+			final EntityA entityA = session.find( EntityA.class, id );
+			final EntityC entityC = new EntityC();
+			entityC.setName( "c" );
+
+			// `#add` triggers the error as it tries to fetch the Set
+			entityA.getAllMyC().add( entityC );
+
+			session.persist( entityC );
+			// todo: this merge fails with a SQL exception
+			//  Syntax error in SQL statement "SELECT A1_0.ALLC,A1_0.ID,A1_0.NAME FROM B_TAB A1_0 WHERE A1_0.ALLC=? AND (A1_0.TYPE = 'C') A1_0[*].TYPE='C' ";
+			session.merge( entityA );
+		} );
+	}
+
+	@Entity(name = "EnttiyA")
+	@Table(name = "a_tab")
+	public static class EntityA {
+		@Id
+		@GeneratedValue
+		private Integer id;
+		private String name;
+
+		@OneToMany
+		@JoinColumn(name = "allC")
+		@Where(clause = "TYPE = 'C'")
+		private Set<EntityC> allMyC;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public void setName(String name) {
+			this.name = name;
+		}
+
+		public Set<EntityC> getAllMyC() {
+			return allMyC;
+		}
+
+		public void setAllMyC(Set<EntityC> allMyC) {
+			this.allMyC = allMyC;
+		}
+	}
+
+	@Entity(name = "EntityB")
+	@Table(name = "b_tab")
+	@DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
+	@DiscriminatorValue( value = "B")
+	public static class EntityB {
+		@Id
+		@GeneratedValue
+		private Integer id;
+		private String name;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public String getName() {
+			return name;
+		}
+
+		public void setName(String name) {
+			this.name = name;
+		}
+	}
+
+	@Entity(name = "EntityC")
+	@DiscriminatorValue(value = "C")
+	public static class EntityC extends EntityB {
+
+	}
+}

hibernate-core/src/test/java/org/hibernate/orm/test/mapping/where/package-info.java

@@ -0,0 +1,12 @@
+/*
+ * 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
+ */
+
+/**
+ * Tests for {@link org.hibernate.annotations.Where}
+ */
+package org.hibernate.orm.test.mapping.where;
+