basic support for DeletedObjects tombstones in the root group.

example/pubspec.lock

@@ -148,6 +148,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.7.0"
+  pedantic:
+    dependency: "direct dev"
+    description:
+      name: pedantic
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.9.2"
   petitparser:
     dependency: transitive
     description:

example/pubspec.yaml

@@ -10,3 +10,6 @@ dependencies:
 
   kdbx:
     path: ../
+
+dev_dependencies:
+  pedantic: ^1.9.2

lib/src/internal/extension_utils.dart

@@ -33,3 +33,7 @@ extension XmlElementExt on xml.XmlElement {
 extension ObjectExt<T> on T {
   R let<R>(R Function(T that) op) => op(this);
 }
+
+extension IterableExt<T> on Iterable<T> {
+  T get singleOrNull => singleWhere((element) => true, orElse: () => null);
+}

lib/src/kdbx_deleted_object.dart

@@ -3,14 +3,15 @@ import 'package:kdbx/src/kdbx_xml.dart';
 import 'package:xml/xml.dart';
 
 class KdbxDeletedObject extends KdbxNode implements KdbxNodeContext {
-  KdbxDeletedObject.create(this.ctx, KdbxUuid uuid)
-      : super.create('DeletedObject') {
+  KdbxDeletedObject.create(this.ctx, KdbxUuid uuid) : super.create(NODE_NAME) {
     _uuid.set(uuid);
     deletionTime.setToNow();
   }
 
   KdbxDeletedObject.read(XmlElement node, this.ctx) : super.read(node);
 
+  static const NODE_NAME = KdbxXml.NODE_DELETED_OBJECT;
+
   @override
   final KdbxReadWriteContext ctx;
 

lib/src/kdbx_entry.dart

@@ -2,6 +2,7 @@ import 'dart:typed_data';
 
 import 'package:kdbx/kdbx.dart';
 import 'package:kdbx/src/crypto/protected_value.dart';
+import 'package:kdbx/src/internal/extension_utils.dart';
 import 'package:kdbx/src/kdbx_binary.dart';
 import 'package:kdbx/src/kdbx_consts.dart';
 import 'package:kdbx/src/kdbx_file.dart';
@@ -255,7 +256,3 @@ class KdbxEntry extends KdbxObject {
     return 'KdbxGroup{uuid=$uuid,name=$label}';
   }
 }
-
-extension<T> on Iterable<T> {
-  T get singleOrNull => singleWhere((element) => true, orElse: () => null);
-}

lib/src/kdbx_format.dart

@@ -12,6 +12,8 @@ import 'package:kdbx/kdbx.dart';
 import 'package:kdbx/src/crypto/key_encrypter_kdf.dart';
 import 'package:kdbx/src/crypto/protected_salt_generator.dart';
 import 'package:kdbx/src/crypto/protected_value.dart';
+import 'package:kdbx/src/internal/extension_utils.dart';
+import 'package:kdbx/src/kdbx_deleted_object.dart';
 import 'package:kdbx/src/utils/byte_utils.dart';
 import 'package:kdbx/src/internal/consts.dart';
 import 'package:kdbx/src/internal/crypto_utils.dart';
@@ -191,7 +193,9 @@ class HashCredentials implements Credentials {
 }
 
 class KdbxBody extends KdbxNode {
-  KdbxBody.create(this.meta, this.rootGroup) : super.create('KeePassFile') {
+  KdbxBody.create(this.meta, this.rootGroup)
+      : _deletedObjects = [],
+        super.create('KeePassFile') {
     node.children.add(meta.node);
     final rootNode = xml.XmlElement(xml.XmlName('Root'));
     node.children.add(rootNode);
@@ -202,11 +206,17 @@ class KdbxBody extends KdbxNode {
     xml.XmlElement node,
     this.meta,
     this.rootGroup,
-  ) : super.read(node);
+    Iterable<KdbxDeletedObject> deletedObjects,
+  )   : _deletedObjects = List.of(deletedObjects),
+        super.read(node);
 
 //  final xml.XmlDocument xmlDocument;
   final KdbxMeta meta;
   final KdbxGroup rootGroup;
+  final List<KdbxDeletedObject> _deletedObjects;
+
+  @visibleForTesting
+  List<KdbxDeletedObject> get deletedObjects => _deletedObjects;
 
   Future<void> writeV3(WriterHelper writer, KdbxFile kdbxFile,
       ProtectedSaltGenerator saltGenerator) async {
@@ -302,7 +312,13 @@ class KdbxBody extends KdbxNode {
       'KeePassFile',
       nest: [
         meta.toXml(),
-        () => builder.element('Root', nest: rootGroupNode),
+        () => builder.element('Root', nest: [
+              rootGroupNode,
+              XmlUtils.createNode(
+                KdbxXml.NODE_DELETED_OBJECTS,
+                _deletedObjects.map((e) => e.toXml()).toList(),
+              ),
+            ]),
       ],
     );
 //    final doc = xml.XmlDocument();
@@ -637,9 +653,16 @@ class KdbxFormat {
     }
 
     final rootGroup =
-        KdbxGroup.read(ctx, null, root.findElements('Group').single);
+        KdbxGroup.read(ctx, null, root.findElements(KdbxXml.NODE_GROUP).single);
+    final deletedObjects = root
+            .findElements(KdbxXml.NODE_DELETED_OBJECTS)
+            .singleOrNull
+            ?.let((el) => el
+                .findElements(KdbxDeletedObject.NODE_NAME)
+                .map((node) => KdbxDeletedObject.read(node, ctx))) ??
+        [];
     _logger.fine('successfully read Meta.');
-    return KdbxBody.read(keePassFile, kdbxMeta, rootGroup);
+    return KdbxBody.read(keePassFile, kdbxMeta, rootGroup, deletedObjects);
   }
 
   Uint8List _decryptContent(

lib/src/kdbx_group.dart

@@ -15,7 +15,7 @@ class KdbxGroup extends KdbxObject {
       : super.create(
           ctx,
           parent?.file,
-          'Group',
+          KdbxXml.NODE_GROUP,
           parent,
         ) {
     this.name.set(name);
@@ -26,7 +26,7 @@ class KdbxGroup extends KdbxObject {
   KdbxGroup.read(KdbxReadWriteContext ctx, KdbxGroup parent, XmlElement node)
       : super.read(ctx, parent, node) {
     node
-        .findElements('Group')
+        .findElements(KdbxXml.NODE_GROUP)
         .map((el) => KdbxGroup.read(ctx, this, el))
         .forEach(_groups.add);
     node

lib/src/kdbx_xml.dart

@@ -14,6 +14,9 @@ class KdbxXml {
   static const NODE_VALUE = 'Value';
   static const ATTR_PROTECTED = 'Protected';
   static const ATTR_COMPRESSED = 'Compressed';
+  static const NODE_GROUP = 'Group';
+  static const NODE_DELETED_OBJECT = 'DeletedObject';
+  static const NODE_DELETED_OBJECTS = 'DeletedObjects';
   static const NODE_HISTORY = 'History';
   static const NODE_BINARIES = 'Binaries';
   static const ATTR_ID = 'ID';

test/deleted_objects_test.dart

@@ -0,0 +1,24 @@
+@Tags(['kdbx4'])
+
+import 'package:logging/logging.dart';
+import 'package:test/test.dart';
+
+import 'internal/test_utils.dart';
+
+final _logger = Logger('deleted_objects_test');
+
+void main() {
+  TestUtil.setupLogging();
+  _logger.finest('Running deleted objects tests.');
+  group('read tombstones', () {
+    test('load/save keeps deleted objects.', () async {
+      final orig =
+          await TestUtil.readKdbxFile('test/test_files/tombstonetest.kdbx');
+      expect(orig.body.deletedObjects, hasLength(1));
+      final dt = orig.body.deletedObjects.first.deletionTime.get();
+      expect([dt.year, dt.month, dt.day], [2020, 8, 30]);
+      final reload = await TestUtil.saveAndRead(orig);
+      expect(reload.body.deletedObjects, hasLength(1));
+    });
+  });
+}