fix(home-following): inbox 중복 insert 처리를 보강한다

src/test/kotlin/kr/co/vividnext/sodalive/v2/home/following/adapter/out/persistence/HomeFollowingNewsInboxPersistenceAdapterRetryTest.kt

@@ -0,0 +1,66 @@
+package kr.co.vividnext.sodalive.v2.home.following.adapter.out.persistence
+
+import kr.co.vividnext.sodalive.v2.home.following.domain.FollowingNewsType
+import kr.co.vividnext.sodalive.v2.home.following.port.out.HomeFollowingNewsInboxRecord
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
+import org.mockito.Mockito
+import org.springframework.dao.DataIntegrityViolationException
+import java.time.LocalDateTime
+import javax.persistence.EntityManager
+
+class HomeFollowingNewsInboxPersistenceAdapterRetryTest {
+    @Test
+    @DisplayName("insertIgnoreAll은 JPA bulk insert unique 충돌 시 기존 row를 재조회하고 남은 row만 재시도한다")
+    fun shouldRetryRemainingRowsWhenBulkInsertConflictsWithExistingRow() {
+        val repository = Mockito.mock(HomeFollowingNewsInboxJpaRepository::class.java)
+        val entityManager = Mockito.mock(EntityManager::class.java)
+        val adapter = HomeFollowingNewsInboxPersistenceAdapter(repository, entityManager)
+        val sourceKey = "CREATOR_RANKING:1:2026-06-25"
+        Mockito.`when`(
+            repository.findExistingMemberIds(
+                FollowingNewsType.CREATOR_RANKING.name,
+                sourceKey,
+                listOf(10L)
+            )
+        ).thenReturn(emptyList()).thenReturn(listOf(10L))
+        Mockito.`when`(repository.saveAll(Mockito.anyList<HomeFollowingNewsInbox>()))
+            .thenThrow(DataIntegrityViolationException("duplicate"))
+
+        val insertedCount = adapter.insertIgnoreAll(
+            listOf(record(memberId = 10L, creatorId = 1L, sourceKey = sourceKey))
+        )
+
+        assertEquals(0, insertedCount)
+        Mockito.verify(repository, Mockito.times(2)).findExistingMemberIds(
+            FollowingNewsType.CREATOR_RANKING.name,
+            sourceKey,
+            listOf(10L)
+        )
+        Mockito.verify(repository, Mockito.times(1)).saveAll(Mockito.anyList<HomeFollowingNewsInbox>())
+    }
+
+    private fun record(
+        memberId: Long,
+        creatorId: Long,
+        sourceKey: String
+    ): HomeFollowingNewsInboxRecord {
+        return HomeFollowingNewsInboxRecord(
+            memberId = memberId,
+            creatorId = creatorId,
+            newsType = FollowingNewsType.CREATOR_RANKING.name,
+            sourceKey = sourceKey,
+            targetId = creatorId,
+            occurredAtUtc = LocalDateTime.of(2026, 6, 25, 0, 0),
+            visibleFromAtUtc = LocalDateTime.of(2026, 6, 25, 9, 0),
+            creatorNickname = "creator-$creatorId",
+            creatorProfileImagePath = "profile-$creatorId.png",
+            title = "title",
+            body = "body",
+            thumbnailImagePath = null,
+            rank = 1,
+            isAdult = false
+        )
+    }
+}

src/test/kotlin/kr/co/vividnext/sodalive/v2/home/following/adapter/out/persistence/HomeFollowingNewsInboxPersistenceAdapterTest.kt

@@ -6,16 +6,17 @@ import kr.co.vividnext.sodalive.member.MemberRole
 import kr.co.vividnext.sodalive.member.following.CreatorFollowing
 import kr.co.vividnext.sodalive.v2.home.following.domain.FollowingNewsType
 import kr.co.vividnext.sodalive.v2.home.following.port.out.HomeFollowingNewsInboxRecord
+import org.junit.jupiter.api.Assertions.assertDoesNotThrow
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertFalse
 import org.junit.jupiter.api.Assertions.assertTrue
 import org.junit.jupiter.api.DisplayName
 import org.junit.jupiter.api.Test
-import org.mockito.Mockito
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest
 import org.springframework.context.annotation.Import
-import org.springframework.dao.DataIntegrityViolationException
+import org.springframework.test.annotation.DirtiesContext
+import org.springframework.test.context.transaction.TestTransaction
 import java.time.LocalDateTime
 import javax.persistence.EntityManager
 
@@ -48,26 +49,21 @@ class HomeFollowingNewsInboxPersistenceAdapterTest @Autowired constructor(
     }
 
     @Test
-    @DisplayName("insertIgnoreAll은 exists 확인 이후 발생한 중복 insert 충돌도 예외 없이 무시한다")
-    fun shouldIgnoreDuplicateInsertRaceAfterExistsCheck() {
-        val mockRepository = Mockito.mock(HomeFollowingNewsInboxJpaRepository::class.java)
-        val mockEntityManager = Mockito.mock(EntityManager::class.java)
-        val raceAdapter = HomeFollowingNewsInboxPersistenceAdapter(mockRepository, mockEntityManager)
-        val record = record(sourceKey = "race-source-key")
-        Mockito.`when`(
-            mockRepository.existsByMemberIdAndNewsTypeAndSourceKey(
-                record.memberId,
-                FollowingNewsType.CREATOR_RANKING,
-                record.sourceKey
-            )
-        ).thenReturn(false, true)
-        Mockito.`when`(mockRepository.saveAndFlush(Mockito.any(HomeFollowingNewsInbox::class.java)))
-            .thenThrow(DataIntegrityViolationException("duplicate"))
+    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
+    @DisplayName("실제 unique 중복 무시 이후 insertIgnoreAll을 호출한 트랜잭션은 커밋 가능하다")
+    fun shouldCommitTransactionAfterRealDuplicateCollisionIsIgnored() {
+        val sourceKey = "real-duplicate"
+        adapter.insertIgnoreAll(listOf(record(sourceKey = sourceKey)))
+        entityManager.flush()
+        entityManager.clear()
 
-        val insertCount = raceAdapter.insertIgnoreAll(listOf(record))
+        val insertCount = adapter.insertIgnoreAll(listOf(record(sourceKey = sourceKey)))
+        val rows = repository.findAll()
 
         assertEquals(0, insertCount)
-        Mockito.verify(mockEntityManager).clear()
+        assertEquals(1, rows.size)
+        TestTransaction.flagForCommit()
+        assertDoesNotThrow { TestTransaction.end() }
     }
 
     @Test