From 6decfa833e2c82313cf7c8f183399f275b5774c1 Mon Sep 17 00:00:00 2001
From: Gerrit Meier <meistermeier@gmail.com>
Date: Mon, 19 Jun 2023 15:59:39 +0200
Subject: [PATCH] GH-2748 - Fix property filter in `FluentQuery...`.

Using FluentQueryByExample/Predicate with a subset of properties,
the underlying fetching mechanics in the Neo4jTemplate was still
querying for everything if the domain has a potential circular dependency.

Closes #2748
---
 .../data/neo4j/repository/query/QueryFragments.java      | 9 ++++++++-
 .../repository/query/QueryFragmentsAndParameters.java    | 1 +
 .../data/neo4j/integration/shared/common/Flight.java     | 3 +++
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragments.java b/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragments.java
index ae90c2b10..c84ccbc0c 100644
--- a/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragments.java
+++ b/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragments.java
@@ -21,6 +21,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Predicate;
 
 import org.apiguardian.api.API;
 import org.neo4j.cypherdsl.core.Condition;
@@ -61,6 +62,7 @@ public final class QueryFragments {
 	 * This flag becomes {@literal true} for backward scrolling keyset pagination. Any {@code AbstractNeo4jQuery} will in turn reverse the result list.
 	 */
 	private boolean requiresReverseSort = false;
+	private Predicate<PropertyFilter.RelaxedPropertyPath> projectingPropertyFilter;
 
 	public void addMatchOn(PatternElement match) {
 		this.matchOn.add(match);
@@ -95,8 +97,13 @@ public final class QueryFragments {
 		this.scalarValueReturn = isScalarValue;
 	}
 
+	public void setProjectingPropertyFilter(Predicate<PropertyFilter.RelaxedPropertyPath> projectingPropertyFilter) {
+		this.projectingPropertyFilter = projectingPropertyFilter;
+	}
+
 	public boolean includeField(PropertyFilter.RelaxedPropertyPath fieldName) {
-		return this.returnTuple == null || this.returnTuple.include(fieldName);
+		return (projectingPropertyFilter == null || projectingPropertyFilter.test(fieldName))
+				&& (this.returnTuple == null || this.returnTuple.include(fieldName));
 	}
 
 	public void setOrderBy(Collection<SortItem> orderBy) {
diff --git a/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragmentsAndParameters.java b/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragmentsAndParameters.java
index 7d837500e..c80ed3071 100644
--- a/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragmentsAndParameters.java
+++ b/src/main/java/org/springframework/data/neo4j/repository/query/QueryFragmentsAndParameters.java
@@ -338,6 +338,7 @@ public final class QueryFragmentsAndParameters {
 		} else {
 			queryFragments.setReturnExpressions(
 					cypherGenerator.createReturnStatementForMatch(entityMetaData, includeField));
+			queryFragments.setProjectingPropertyFilter(includeField);
 		}
 
 		if (pageable != null) {
diff --git a/src/test/java/org/springframework/data/neo4j/integration/shared/common/Flight.java b/src/test/java/org/springframework/data/neo4j/integration/shared/common/Flight.java
index ef8ff2eb1..57ba60f18 100644
--- a/src/test/java/org/springframework/data/neo4j/integration/shared/common/Flight.java
+++ b/src/test/java/org/springframework/data/neo4j/integration/shared/common/Flight.java
@@ -36,6 +36,9 @@ public class Flight {
 	@Relationship(type = "ARRIVES")
 	private final Airport arrival;
 
+	@Relationship("NEXT_FLIGHT")
+	private Flight nextFlight;
+
 	public Flight(String name, Airport departure, Airport arrival) {
 		this.name = name;
 		this.departure = departure;