From d95d7cd3f7239580360eb0eb5228bee29b14cfe4 Mon Sep 17 00:00:00 2001
From: Lukas Kubanek <lukas.kubanek@me.com>
Date: Wed, 4 Mar 2026 11:41:20 +0100
Subject: [PATCH 1/2] Add assertion exposing mock notify() mutation

---
 .../CloudKitTests/MergeConflictTests.swift    | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/Tests/SQLiteDataTests/CloudKitTests/MergeConflictTests.swift b/Tests/SQLiteDataTests/CloudKitTests/MergeConflictTests.swift
index 34530951..38bcd913 100644
--- a/Tests/SQLiteDataTests/CloudKitTests/MergeConflictTests.swift
+++ b/Tests/SQLiteDataTests/CloudKitTests/MergeConflictTests.swift
@@ -357,6 +357,51 @@
           }
         }
         await modificationCallback.notify()
+        
+        assertInlineSnapshot(of: container, as: .customDump) {
+          """
+          MockCloudContainer(
+            privateCloudDatabase: MockCloudDatabase(
+              databaseScope: .private,
+              storage: [
+                [0]: CKRecord(
+                  recordID: CKRecord.ID(1:reminders/zone/__defaultOwner__),
+                  recordType: "reminders",
+                  parent: CKReference(recordID: CKRecord.ID(1:remindersLists/zone/__defaultOwner__)),
+                  share: nil,
+                  dueDate🗓️: 0,
+                  id: 1,
+                  id🗓️: 0,
+                  isCompleted: 0,
+                  isCompleted🗓️: 0,
+                  priority🗓️: 0,
+                  remindersListID: 1,
+                  remindersListID🗓️: 0,
+                  title: "Buy milk",
+                  title🗓️: 30,
+                  🗓️: 30
+                ),
+                [1]: CKRecord(
+                  recordID: CKRecord.ID(1:remindersLists/zone/__defaultOwner__),
+                  recordType: "remindersLists",
+                  parent: nil,
+                  share: nil,
+                  id: 1,
+                  id🗓️: 0,
+                  title: "",
+                  title🗓️: 0,
+                  🗓️: 0
+                )
+              ]
+            ),
+            sharedCloudDatabase: MockCloudDatabase(
+              databaseScope: .shared,
+              storage: []
+            )
+          )
+          """
+        }
+        
         try await syncEngine.processPendingRecordZoneChanges(scope: .private)
 
         assertInlineSnapshot(of: container, as: .customDump) {

From db42b453cf936f94a14fa1e4203b418d7e368a46 Mon Sep 17 00:00:00 2001
From: Lukas Kubanek <lukas.kubanek@me.com>
Date: Wed, 4 Mar 2026 11:41:37 +0100
Subject: [PATCH 2/2] Copy records in notify() to prevent MockCloudDatabase
 mutation

---
 Tests/SQLiteDataTests/Internal/CloudKitTestHelpers.swift | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Tests/SQLiteDataTests/Internal/CloudKitTestHelpers.swift b/Tests/SQLiteDataTests/Internal/CloudKitTestHelpers.swift
index 4716be7b..1f9a6109 100644
--- a/Tests/SQLiteDataTests/Internal/CloudKitTestHelpers.swift
+++ b/Tests/SQLiteDataTests/Internal/CloudKitTestHelpers.swift
@@ -93,7 +93,10 @@ extension SyncEngine {
     return ModifyRecordsCallback {
       await syncEngine.parentSyncEngine.handleEvent(
         .fetchedRecordZoneChanges(
-          modifications: saveResults.values.compactMap { try? $0.get() },
+          modifications: saveResults.values.compactMap {
+            guard let record = try? $0.get() else { return nil }
+            return record.copy() as? CKRecord
+          },
           deletions: deleteResults.compactMap { recordID, result in
             (recordsToDeleteByID[recordID]?.recordType).flatMap { recordType in
               (try? result.get()) != nil