Set CKRecord.modificationDate in MockCloudDatabase

Sources/SQLiteData/CloudKit/CloudKit+StructuredQueries.swift

@@ -24,9 +24,7 @@
     public var queryBinding: QueryBinding {
       let archiver = NSKeyedArchiver(requiringSecureCoding: true)
       queryOutput.encodeSystemFields(with: archiver)
-      if isTesting {
-        archiver.encode(queryOutput._recordChangeTag, forKey: "_recordChangeTag")
-      }
+      queryOutput.encodeMockSystemFieldsIfNeeded(with: archiver)
       return archiver.encodedData.queryBinding
     }
 
@@ -44,16 +42,12 @@
     }
 
     private init(data: Data) throws {
-      let coder = try NSKeyedUnarchiver(forReadingFrom: data)
-      coder.requiresSecureCoding = true
-      guard let queryOutput = Record(coder: coder) else {
+      let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data)
+      unarchiver.requiresSecureCoding = true
+      guard let queryOutput = Record(coder: unarchiver) else {
         throw DecodingError()
       }
-      if isTesting {
-        queryOutput._recordChangeTag =
-          coder
-          .decodeObject(of: NSNumber.self, forKey: "_recordChangeTag")?.intValue
-      }
+      queryOutput.decodeMockSystemFieldsIfNeeded(from: unarchiver)
       self.init(queryOutput: queryOutput)
     }
 
@@ -66,9 +60,7 @@
     public var queryBinding: QueryBinding {
       let archiver = NSKeyedArchiver(requiringSecureCoding: true)
       queryOutput.encode(with: archiver)
-      if isTesting {
-        archiver.encode(queryOutput._recordChangeTag, forKey: "_recordChangeTag")
-      }
+      queryOutput.encodeMockSystemFieldsIfNeeded(with: archiver)
       return archiver.encodedData.queryBinding
     }
 
@@ -86,22 +78,44 @@
     }
 
     private init(data: Data) throws {
-      let coder = try NSKeyedUnarchiver(forReadingFrom: data)
-      coder.requiresSecureCoding = true
-      guard let queryOutput = Record(coder: coder) else {
+      let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data)
+      unarchiver.requiresSecureCoding = true
+      guard let queryOutput = Record(coder: unarchiver) else {
         throw DecodingError()
       }
-      if isTesting {
-        queryOutput._recordChangeTag =
-          coder
-          .decodeObject(of: NSNumber.self, forKey: "_recordChangeTag")?.intValue
-      }
+      queryOutput.decodeMockSystemFieldsIfNeeded(from: unarchiver)
       self.init(queryOutput: queryOutput)
     }
 
     private struct DecodingError: Error {}
   }
 
+  extension CKRecord {
+    fileprivate func encodeMockSystemFieldsIfNeeded(with coder: NSKeyedArchiver) {
+      guard isTesting else { return }
+      coder.encode(
+        self._recordChangeTag,
+        forKey: "_recordChangeTag"
+      )
+      coder.encode(
+        self._modificationDate.map { $0 as NSDate },
+        forKey: "_modificationDate"
+      )
+    }
+
+    fileprivate func decodeMockSystemFieldsIfNeeded(from coder: NSKeyedUnarchiver) {
+      guard isTesting else { return }
+      self._recordChangeTag = coder.decodeObject(
+        of: NSNumber.self,
+        forKey: "_recordChangeTag"
+      )?.intValue
+      self._modificationDate = coder.decodeObject(
+        of: NSDate.self,
+        forKey: "_modificationDate"
+      ) as Date?
+    }
+  }
+
   extension CKDatabase.Scope {
     public struct RawValueRepresentation: QueryBindable, QueryRepresentable {
       public let queryOutput: CKDatabase.Scope

Sources/SQLiteData/CloudKit/Internal/CKRecord+MockSystemFields.swift

@@ -0,0 +1,47 @@
+#if canImport(CloudKit)
+  import CloudKit
+  import IssueReporting
+  import ObjectiveC
+
+  nonisolated(unsafe) private var modificationDateKey: UInt8 = 0
+
+  extension CKRecord {
+    var _modificationDate: Date? {
+      get {
+        objc_getAssociatedObject(self, &modificationDateKey) as? Date
+      }
+      set {
+        installMockSystemFieldOverridesOnce()
+        objc_setAssociatedObject(self, &modificationDateKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
+      }
+    }
+
+    @objc fileprivate dynamic func _swizzled_modificationDate() -> Date? {
+      if let override = objc_getAssociatedObject(self, &modificationDateKey) as? Date {
+        return override
+      }
+      return self._swizzled_modificationDate()
+    }
+  }
+
+  private func installMockSystemFieldOverridesOnce() {
+    _ = token
+  }
+
+  private let token: Void = {
+    guard
+      let originalMethod = class_getInstanceMethod(
+        CKRecord.self,
+        #selector(getter: CKRecord.modificationDate)
+      ),
+      let swizzledMethod = class_getInstanceMethod(
+        CKRecord.self,
+        #selector(CKRecord._swizzled_modificationDate)
+      )
+    else {
+      reportIssue("Failed to swizzle CKRecord.modificationDate")
+      return
+    }
+    method_exchangeImplementations(originalMethod, swizzledMethod)
+  }()
+#endif

Sources/SQLiteData/CloudKit/Internal/MockCloudDatabase.swift

@@ -11,13 +11,18 @@
 
     package struct State {
       private var lastRecordChangeTag = 0
+      private var lastModificationDate = 0
       package var storage: [CKRecordZone.ID: Zone] = [:]
       var assets: [AssetID: Data] = [:]
       var deletedRecords: [(CKRecord.ID, CKRecord.RecordType)] = []
       mutating func nextRecordChangeTag() -> Int {
         lastRecordChangeTag += 1
         return lastRecordChangeTag
       }
+      mutating func nextModificationDate() -> Date {
+        lastModificationDate += 1
+        return Date(timeIntervalSinceReferenceDate: TimeInterval(lastModificationDate))
+      }
     }
 
     struct AssetID: Hashable {
@@ -112,6 +117,7 @@
 
         switch savePolicy {
         case .ifServerRecordUnchanged:
+          let batchModificationDate = state.nextModificationDate()
           for recordToSave in recordsToSave {
             if let share = recordToSave as? CKShare {
               let isSavingRootRecord = recordsToSave.contains(where: {
@@ -189,6 +195,7 @@
               guard let copy = recordToSave.copy() as? CKRecord
               else { fatalError("Could not copy CKRecord.") }
               copy._recordChangeTag = state.nextRecordChangeTag()
+              copy._modificationDate = batchModificationDate
 
               for key in copy.allKeys() {
                 guard let assetURL = (copy[key] as? CKAsset)?.fileURL

Tests/SQLiteDataTests/CloudKitTests/MergeConflictTests.swift

@@ -14,7 +14,7 @@
     @Suite(.printTimestamps) final class MergeConflictTests: BaseCloudKitTests, @unchecked Sendable
     {
       @available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
-      @Test func merge_clientRecordUpdatedBeforeServerRecord() async throws {
+      @Test func clientRecordUpdatedBeforeServerRecord() async throws {
         try await userDatabase.userWrite { db in
           try db.seed {
             RemindersList(id: 1, title: "")
@@ -143,7 +143,7 @@
                   id: 1,
                   id🗓️: 0,
                   isCompleted: 1,
-                  isCompleted🗓️: 30,
+                  isCompleted🗓️: 60,
                   priority🗓️: 0,
                   remindersListID: 1,
                   remindersListID🗓️: 0,

Tests/SQLiteDataTests/CloudKitTests/MockCloudDatabaseTests.swift

@@ -705,6 +705,31 @@
         #expect(error?.code == .limitExceeded)
       }
 
+      @available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
+      @Test func modificationDateIncreasesOnSubsequentSaves() throws {
+        let record = CKRecord(recordType: "A", recordID: CKRecord.ID(recordName: "A"))
+
+        let (results1, _) = try syncEngine.private.database.modifyRecords(saving: [record])
+        let saved1 = try #require(try results1[record.recordID]?.get())
+        #expect(saved1.modificationDate == Date(timeIntervalSinceReferenceDate: 1))
+
+        let (results2, _) = try syncEngine.private.database.modifyRecords(saving: [saved1])
+        let saved2 = try #require(try results2[record.recordID]?.get())
+        #expect(saved2.modificationDate == Date(timeIntervalSinceReferenceDate: 2))
+      }
+
+      @available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
+      @Test func modificationDateIsSharedWithinBatch() throws {
+        let recordA = CKRecord(recordType: "A", recordID: CKRecord.ID(recordName: "A"))
+        let recordB = CKRecord(recordType: "B", recordID: CKRecord.ID(recordName: "B"))
+
+        let (saveResults, _) = try syncEngine.private.database.modifyRecords(saving: [recordA, recordB])
+        let savedA = try #require(try saveResults[recordA.recordID]?.get())
+        let savedB = try #require(try saveResults[recordB.recordID]?.get())
+
+        #expect(savedA.modificationDate == savedB.modificationDate)
+      }
+
       @Test func records_limitExceeded() async throws {
         let remindersListRecord = CKRecord(
           recordType: RemindersList.tableName,

Tests/SQLiteDataTests/CloudKitTests/MockSystemFieldsTests.swift

@@ -0,0 +1,42 @@
+#if canImport(CloudKit)
+  import CloudKit
+  @testable import SQLiteData
+  import Testing
+
+  @Suite
+  struct MockSystemFieldsTests {
+    @Test func modificationDateOverride() {
+      let record = CKRecord(recordType: "record", recordID: CKRecord.ID(recordName: "A"))
+      #expect(record.modificationDate == nil)
+
+      record._modificationDate = Date(timeIntervalSinceReferenceDate: 1)
+      #expect(record.modificationDate == Date(timeIntervalSinceReferenceDate: 1))
+    }
+
+    @available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
+    @Test func systemFieldsRepresentationRoundtrip() throws {
+      let record = CKRecord(recordType: "record", recordID: CKRecord.ID(recordName: "A"))
+      record._recordChangeTag = 42
+      record._modificationDate = Date(timeIntervalSinceReferenceDate: 1)
+
+      let representation = CKRecord.SystemFieldsRepresentation(queryOutput: record)
+      let result = try #require(CKRecord.SystemFieldsRepresentation(queryBinding: representation.queryBinding))
+
+      #expect(result.queryOutput._recordChangeTag == 42)
+      #expect(result.queryOutput._modificationDate == Date(timeIntervalSinceReferenceDate: 1))
+    }
+
+    @available(iOS 17, macOS 14, tvOS 17, watchOS 10, *)
+    @Test func allFieldsRepresentationRoundtrip() throws {
+      let record = CKRecord(recordType: "record", recordID: CKRecord.ID(recordName: "A"))
+      record._recordChangeTag = 42
+      record._modificationDate = Date(timeIntervalSinceReferenceDate: 1)
+
+      let representation = CKRecord._AllFieldsRepresentation(queryOutput: record)
+      let result = try #require(CKRecord._AllFieldsRepresentation(queryBinding: representation.queryBinding))
+
+      #expect(result.queryOutput._recordChangeTag == 42)
+      #expect(result.queryOutput._modificationDate == Date(timeIntervalSinceReferenceDate: 1))
+    }
+  }
+#endif