HSEARCH-3319 WIP: DRAFT: IDEA: TEST: Type-safe field references

documentation/src/test/java/org/hibernate/search/documentation/search/predicate/FieldReferenceIT.java

@@ -0,0 +1,254 @@
+/*
+ * 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.search.documentation.search.predicate;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.hibernate.search.util.impl.integrationtest.mapper.orm.OrmUtils.with;
+
+import java.util.List;
+import java.util.function.Consumer;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityManagerFactory;
+import jakarta.persistence.Id;
+
+import org.hibernate.search.documentation.testsupport.BackendConfigurations;
+import org.hibernate.search.documentation.testsupport.DocumentationSetupHelper;
+import org.hibernate.search.engine.backend.types.Projectable;
+import org.hibernate.search.engine.search.common.ValueConvert;
+import org.hibernate.search.engine.search.predicate.SearchPredicate;
+import org.hibernate.search.engine.search.reference.traits.predicate.MatchPredicateFieldReference;
+import org.hibernate.search.engine.search.reference.traits.projection.FieldProjectionFieldReference;
+import org.hibernate.search.mapper.orm.Search;
+import org.hibernate.search.mapper.orm.scope.SearchScope;
+import org.hibernate.search.mapper.orm.session.SearchSession;
+import org.hibernate.search.mapper.pojo.mapping.definition.annotation.FullTextField;
+import org.hibernate.search.mapper.pojo.mapping.definition.annotation.Indexed;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+class FieldReferenceIT {
+
+	@RegisterExtension
+	public DocumentationSetupHelper setupHelper = DocumentationSetupHelper.withSingleBackend( BackendConfigurations.simple() );
+
+	private EntityManagerFactory entityManagerFactory;
+
+	@BeforeEach
+	void setup() {
+		entityManagerFactory = setupHelper.start().setup( EntityA.class, EntityB.class, EntityC.class );
+		initData();
+	}
+
+	@Test
+	void smoke() {
+		withinSearchSession( searchSession -> {
+			assertThat(
+					searchSession.search( EntityA.class )
+							.select( f -> f.field( EntityA_.stringA ) )
+							.where( f -> f.match().field( EntityA_.stringA ).matching( "a" ) )
+							.fetchHits( 20 )
+			).containsOnly( "a" );
+
+			assertThat(
+					searchSession.search( EntityA.class )
+							.select( f -> f.field( EntityC_.stringA ) )
+							.where( f -> f.match().field( EntityC_.stringC ).matching( "c" ) )
+							.fetchHits( 20 )
+			).containsOnly( "c" );
+
+			SearchScope<EntityB> scope = searchSession.scope( List.of( EntityB.class, EntityC.class ) );
+			SearchPredicate searchPredicate = scope.predicate().match().field( EntityB_.stringA ).matching( "b" ).toPredicate();
+			SearchPredicate searchPredicate2 =
+					scope.predicate().match().field( EntityC_.stringC ).matching( "c" ).toPredicate();
+
+			assertThat(
+					searchSession.search( scope )
+							.select( f -> f.field( EntityC_.stringA ) )
+							.where( searchPredicate )
+							.fetchHits( 20 )
+			).containsOnly( "b" );
+
+			assertThat(
+					searchSession.search( scope )
+							.select( f -> f.field( EntityC_.stringA ) )
+							.where( searchPredicate2 )
+							.fetchHits( 20 )
+			).containsOnly( "c" );
+
+		} );
+	}
+
+	private void initData() {
+		with( entityManagerFactory ).runInTransaction( entityManager -> {
+			EntityA a = new EntityA();
+			a.id = 1L;
+			a.stringA = "a";
+
+			EntityB b = new EntityB();
+			b.id = 10L;
+			b.stringA = "b";
+			b.stringB = "b";
+
+			EntityC c = new EntityC();
+			c.id = 100L;
+			c.stringA = "c";
+			c.stringB = "c";
+			c.stringC = "c";
+
+			entityManager.persist( a );
+			entityManager.persist( b );
+			entityManager.persist( c );
+		} );
+	}
+
+	@Indexed
+	@Entity
+	public static class EntityA {
+		@Id
+		Long id;
+
+		@FullTextField(projectable = Projectable.YES)
+		String stringA;
+
+	}
+
+	@Entity
+	public static class EntityB extends EntityA {
+
+		@FullTextField(projectable = Projectable.YES)
+		String stringB;
+
+	}
+
+	@Entity
+	public static class EntityC extends EntityB {
+
+		@FullTextField(projectable = Projectable.YES)
+		String stringC;
+
+	}
+
+
+	public static class EntityA_ {
+		public static ValueFieldReference1<EntityA, String, String, String> stringA;
+
+		static {
+			stringA = ValueFieldReference1.of( "stringA", EntityA.class, String.class, String.class, String.class );
+		}
+	}
+
+	public static class EntityB_ {
+		public static ValueFieldReference1<EntityB, String, String, String> stringA;
+		public static ValueFieldReference1<EntityB, String, String, String> stringB;
+
+		static {
+			stringA = ValueFieldReference1.of( "stringA", EntityB.class, String.class, String.class, String.class );
+			stringB = ValueFieldReference1.of( "stringB", EntityB.class, String.class, String.class, String.class );
+		}
+	}
+
+	public static class EntityC_ {
+		public static ValueFieldReference1<EntityC, String, String, String> stringA;
+		public static ValueFieldReference1<EntityC, String, String, String> stringB;
+		public static ValueFieldReference1<EntityC, String, String, String> stringC;
+
+		static {
+			stringA = ValueFieldReference1.of( "stringA", EntityC.class, String.class, String.class, String.class );
+			stringB = ValueFieldReference1.of( "stringB", EntityC.class, String.class, String.class, String.class );
+			stringC = ValueFieldReference1.of( "stringC", EntityC.class, String.class, String.class, String.class );
+		}
+	}
+
+
+	public static class ValueFieldReference1<E, T, V, P> extends TypedFieldReference1<E, T, P> {
+
+		public static <E, T, V, P> ValueFieldReference1<E, T, V, P> of(
+				String path,
+				Class<E> documentReferenceClass,
+				Class<T> t,
+				Class<V> v,
+				Class<P> p) {
+			return new ValueFieldReference1<>( path, documentReferenceClass, t, v, p );
+		}
+
+		private final TypedFieldReference1<E, V, V> noConverter;
+		private final TypedFieldReference1<E, String, String> string;
+
+		public ValueFieldReference1(String absolutePath, Class<E> containing, Class<T> inputType, Class<V> indexType,
+				Class<P> projectionType) {
+			super( absolutePath, ValueConvert.YES, containing, inputType, projectionType );
+			this.noConverter = new TypedFieldReference1<>( absolutePath, ValueConvert.NO, containing, indexType, indexType );
+			this.string =
+					new TypedFieldReference1<>( absolutePath, ValueConvert.PARSE, containing, String.class, String.class );
+		}
+
+		public TypedFieldReference1<E, V, V> noConverter() {
+			return noConverter;
+		}
+
+
+		public TypedFieldReference1<E, String, String> asString() {
+			return string;
+		}
+
+	}
+
+	public static class TypedFieldReference1<E, T, P>
+			implements FieldProjectionFieldReference<E, P>,
+			MatchPredicateFieldReference<E, T> {
+
+		private final String absolutePath;
+		private final ValueConvert valueConvert;
+		private final Class<E> containing;
+		private final Class<T> input;
+		private final Class<P> projection;
+
+		public TypedFieldReference1(String absolutePath, ValueConvert valueConvert, Class<E> containing, Class<T> input,
+				Class<P> projection) {
+			this.absolutePath = absolutePath;
+			this.valueConvert = valueConvert;
+			this.containing = containing;
+			this.input = input;
+			this.projection = projection;
+		}
+
+		@Override
+		public String absolutePath() {
+			return absolutePath;
+		}
+
+		@Override
+		public Class<T> predicateType() {
+			return input;
+		}
+
+		@Override
+		public ValueConvert valueConvert() {
+			return valueConvert;
+		}
+
+		@Override
+		public Class<P> projectionType() {
+			return projection;
+		}
+
+		@Override
+		public Class<E> containing() {
+			return containing;
+		}
+	}
+
+	private void withinSearchSession(Consumer<SearchSession> action) {
+		with( entityManagerFactory ).runInTransaction( entityManager -> {
+			SearchSession searchSession = Search.session( entityManager );
+			action.accept( searchSession );
+		} );
+	}
+}