From e882594f89bb679cec15e42b58b0656787b50445 Mon Sep 17 00:00:00 2001
From: Faron Dutton <faron.dutton@insightglobal.com>
Date: Fri, 22 Nov 2024 10:18:19 -0500
Subject: [PATCH] Adds failing unit-test for StringBasedAggregation
 projections.

See #4839
Original pull request: #4841
---
 .../repository/AbstractPersonRepositoryIntegrationTests.java | 5 +++++
 .../data/mongodb/repository/PersonRepository.java            | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/AbstractPersonRepositoryIntegrationTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/AbstractPersonRepositoryIntegrationTests.java
index 33720d255..20e333e34 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/AbstractPersonRepositoryIntegrationTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/AbstractPersonRepositoryIntegrationTests.java
@@ -1275,6 +1275,11 @@ public abstract class AbstractPersonRepositoryIntegrationTests implements Dirtie
 		assertThat(repository.findClosedProjectionBy()).isNotEmpty();
 	}
 
+	@Test // https://github.com/spring-projects/spring-data-mongodb/issues/4839
+    void findAggregatedClosedProjectionBy() {
+        assertThat(repository.findAggregatedClosedProjectionBy()).isNotEmpty();
+    }
+
 	@Test // DATAMONGO-1865
 	void findFirstEntityReturnsFirstResultEvenForNonUniqueMatches() {
 		assertThat(repository.findFirstBy()).isNotNull();
diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/PersonRepository.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/PersonRepository.java
index c2036cabf..09ead8061 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/PersonRepository.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/repository/PersonRepository.java
@@ -386,6 +386,10 @@ public interface PersonRepository extends MongoRepository<Person, String>, Query
 	// DATAMONGO-1752
 	Iterable<PersonSummary> findClosedProjectionBy();
 
+    // https://github.com/spring-projects/spring-data-mongodb/issues/4839
+	@Aggregation("{ '$project': { _id : 0, firstName : 1, lastname : 1 } }")
+    Iterable<PersonSummary> findAggregatedClosedProjectionBy();
+
 	@Query(sort = "{ age : -1 }")
 	List<Person> findByAgeGreaterThan(int age);