crossmate

commit c5b5e6280d4b6b1100679b6d015f5835b89b5b6c
parent 66547492b54fbf359c3d21b8b8f8b7b87958d3cf
Author: Michael Camilleri <[email protected]>
Date:   Thu, 14 May 2026 14:35:37 +0900

Avoid updated timestamps in Game records being overwritten with earlier timestamps

Diffstat:
M
Crossmate/Sync/RecordSerializer.swift
 | 
12
+++++++++---
M
Tests/Unit/RecordSerializerTests.swift
 | 
29
+++++++++++++++++++++++++++++

2 files changed, 38 insertions(+), 3 deletions(-)
diff --git a/Crossmate/Sync/RecordSerializer.swift b/Crossmate/Sync/RecordSerializer.swift
@@ -342,12 +342,18 @@ enum RecordSerializer {
         }
 
         // Seed createdAt/updatedAt from the server record so the library
-        // can order newly-arrived games. The CKRecord timestamps are the
-        // source of truth when we don't have a local creation event.
+        // can order newly-arrived games. After that, Game records may lag
+        // behind fresher Moves timestamps, so never move updatedAt backward.
         if entity.createdAt == nil {
             entity.createdAt = record.creationDate ?? Date()
         }
-        entity.updatedAt = record.modificationDate ?? entity.updatedAt ?? Date()
+        if let modificationDate = record.modificationDate {
+            if entity.updatedAt.map({ $0 < modificationDate }) ?? true {
+                entity.updatedAt = modificationDate
+            }
+        } else if entity.updatedAt == nil {
+            entity.updatedAt = Date()
+        }
 
         entity.ckRecordName = recordName
         entity.ckSystemFields = encodeSystemFields(of: record)
diff --git a/Tests/Unit/RecordSerializerTests.swift b/Tests/Unit/RecordSerializerTests.swift
@@ -135,6 +135,35 @@ struct RecordSerializerTests {
         #expect(merged.title == "Updated")       // mutable field updated
     }
 
+    @Test("applyGameRecord does not lower an existing updatedAt")
+    @MainActor func applyGameRecordPreservesFresherUpdatedAt() throws {
+        let persistence = makeTestPersistence()
+        let ctx = persistence.viewContext
+        let gameID = UUID()
+        let zone = RecordSerializer.zoneID(for: gameID)
+        let recordName = RecordSerializer.recordName(forGameID: gameID)
+        let recordID = CKRecord.ID(recordName: recordName, zoneID: zone)
+
+        let entity = GameEntity(context: ctx)
+        let newerUpdatedAt = Date(timeIntervalSince1970: 1_700_000_500)
+        entity.id = gameID
+        entity.ckRecordName = recordName
+        entity.title = "Local"
+        entity.puzzleSource = ""
+        entity.createdAt = Date(timeIntervalSince1970: 1_700_000_000)
+        entity.updatedAt = newerUpdatedAt
+
+        let record = CKRecord(recordType: "Game", recordID: recordID)
+        record["title"] = "Remote" as CKRecordValue
+
+        let merged = RecordSerializer.applyGameRecord(record, to: ctx)
+        try ctx.save()
+
+        #expect(merged === entity)
+        #expect(merged.title == "Remote")
+        #expect(merged.updatedAt == newerUpdatedAt)
+    }
+
     // MARK: - System fields round-trip
 
     @Test("Encode and decode system fields preserves record type and zone")