Fix issue with collection types directly referenced on the root entity

Author: christophstrobl

spring-data-jpa/src/main/java/org/springframework/data/jpa/repository/query/JpqlUtils.java

@@ -17,6 +17,7 @@
 
 import jakarta.persistence.metamodel.Attribute;
 import jakarta.persistence.metamodel.Bindable;
+import jakarta.persistence.metamodel.EntityType;
 import jakarta.persistence.metamodel.ManagedType;
 import jakarta.persistence.metamodel.Metamodel;
 
@@ -85,6 +86,11 @@ public JpqlQueryBuilder.PathExpression toExpressionRecursively(Metamodel metamod
 
 			// if it's a leaf, return the join
 			if (isLeafProperty) {
+
+				// except its a collection type on the root
+				if (from instanceof EntityType<?> && property.isCollection()) {
+					return new JpqlQueryBuilder.PathAndOrigin(property, source, false);
+				}
 				return new JpqlQueryBuilder.PathAndOrigin(property, joinSource, true);
 			}
 

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/query/JpqlQueryBuilderUnitTests.java

@@ -264,6 +264,67 @@ void referencesCollectionViaJoin() {
 				"SELECT r FROM JpqlQueryBuilderUnitTests$Race r LEFT JOIN r.lineup l WHERE l.groups IS NOT EMPTY");
 	}
 
+	@Test // GH-4110
+	void referencesCollectionViaMultipleJoins() {
+
+		TestMetaModel model = TestMetaModel.hibernateModel(TestUser.class, TestRole.class);
+		Entity entity = entity(TestUser.class);
+
+		EntityType<TestUser> entityType = model.entity(TestUser.class);
+		JpqlQueryBuilder.PathExpression pas = JpqlUtils.toExpressionRecursively(model, entity, entityType,
+				PropertyPath.from("manager.colleagues.roles", TestUser.class));
+		String jpql = JpqlQueryBuilder.selectFrom(entity).entity().where(JpqlQueryBuilder.where(pas).isEmpty()).render();
+
+		assertThat(jpql).isEqualTo(
+				"SELECT t FROM JpqlQueryBuilderUnitTests$TestUser t LEFT JOIN t.manager m LEFT JOIN m.colleagues c WHERE c.roles IS EMPTY");
+	}
+
+	@Test // GH-4110
+	void referencesCollectionViaJoinWithMemberOf() {
+
+		TestMetaModel model = TestMetaModel.hibernateModel(TestUser.class, TestRole.class);
+		Entity entity = entity(TestUser.class);
+
+		EntityType<TestUser> entityType = model.entity(TestUser.class);
+		JpqlQueryBuilder.PathExpression pas = JpqlUtils.toExpressionRecursively(model, entity, entityType,
+				PropertyPath.from("colleagues.roles", TestUser.class));
+		String jpql = JpqlQueryBuilder.selectFrom(entity).entity()
+				.where(JpqlQueryBuilder.where(pas).memberOf(JpqlQueryBuilder.parameter("?1"))).render();
+
+		assertThat(jpql).isEqualTo(
+				"SELECT t FROM JpqlQueryBuilderUnitTests$TestUser t LEFT JOIN t.colleagues c WHERE ?1 MEMBER OF c.roles");
+	}
+
+	@Test // GH-4110
+	void directCollectionPropertyDoesNotCreateJoin() {
+
+		TestMetaModel model = TestMetaModel.hibernateModel(TestUser.class, TestRole.class);
+		Entity entity = entity(TestUser.class);
+
+		EntityType<TestUser> entityType = model.entity(TestUser.class);
+		JpqlQueryBuilder.PathExpression pas = JpqlUtils.toExpressionRecursively(model, entity, entityType,
+				PropertyPath.from("roles", TestUser.class));
+		String jpql = JpqlQueryBuilder.selectFrom(entity).entity().where(JpqlQueryBuilder.where(pas).isEmpty()).render();
+
+		assertThat(jpql).isEqualTo("SELECT t FROM JpqlQueryBuilderUnitTests$TestUser t WHERE t.roles IS EMPTY");
+	}
+
+	@Test // GH-4110
+	void collectionWithAdditionalPathSegments() {
+
+		TestMetaModel model = TestMetaModel.hibernateModel(TestUser.class, TestRole.class);
+		Entity entity = entity(TestUser.class);
+
+		EntityType<TestUser> entityType = model.entity(TestUser.class);
+		JpqlQueryBuilder.PathExpression pas = JpqlUtils.toExpressionRecursively(model, entity, entityType,
+				PropertyPath.from("colleagues.roles.name", TestUser.class));
+		String jpql = JpqlQueryBuilder.selectFrom(entity).entity()
+				.where(JpqlQueryBuilder.where(pas).eq(literal("ADMIN"))).render();
+
+		assertThat(jpql).isEqualTo(
+				"SELECT t FROM JpqlQueryBuilderUnitTests$TestUser t LEFT JOIN t.colleagues c LEFT JOIN c.roles r WHERE r.name = 'ADMIN'");
+	}
+
 	static ContextualAssert contextual(RenderContext context) {
 		return new ContextualAssert(context);
 	}
@@ -385,4 +446,20 @@ static class GroupId {
 
 	}
 
+	@jakarta.persistence.Entity
+	static class TestUser {
+
+		@Id long id;
+		@ManyToOne TestUser manager;
+		@OneToMany Set<TestUser> colleagues = new HashSet<>();
+		@OneToMany Set<TestRole> roles = new HashSet<>();
+	}
+
+	@jakarta.persistence.Entity
+	static class TestRole {
+
+		@Id long id;
+		String name;
+	}
+
 }