Add support for dataIdFromObject to ferry_cache and swap the order of…

… assignment in denormalize_fragment

ferry_cache/lib/src/cache.dart

@@ -13,6 +13,7 @@ class Cache {
   final Map<String, TypePolicy> typePolicies;
   final bool addTypename;
   final Store store;
+  final utils.DataIdResolver? dataIdFromObject;
 
   @visibleForTesting
   final BehaviorSubject<
@@ -24,12 +25,14 @@ class Cache {
 
   Cache({
     Store? store,
+    utils.DataIdResolver? dataIdFromObject,
     this.typePolicies = const {},
     this.addTypename = true,
     Map<OperationRequest, Map<String, Map<String, dynamic>?>>
         seedOptimisticPatches = const {},
   })  : store = store ?? MemoryStore(),
-        optimisticPatchesStream = BehaviorSubject.seeded(seedOptimisticPatches);
+        optimisticPatchesStream = BehaviorSubject.seeded(seedOptimisticPatches),
+        dataIdFromObject = dataIdFromObject;
 
   /// Reads data for the given [dataId] from the [Store], merging in any data from optimistic patches
   @visibleForTesting
@@ -62,6 +65,7 @@ class Cache {
           store,
           typePolicies,
           addTypename,
+          dataIdFromObject: dataIdFromObject,
         ).doOnDone(() => closed = true);
 
         return NeverStream<TData?>()
@@ -97,6 +101,7 @@ class Cache {
           store,
           typePolicies,
           addTypename,
+          dataIdFromObject: dataIdFromObject,
         ).doOnDone(() => closed = true);
 
         return NeverStream<TData?>()
@@ -129,6 +134,7 @@ class Cache {
       // TODO: don't cast to dynamic
       variables: (request.vars as dynamic)?.toJson(),
       typePolicies: typePolicies,
+      dataIdFromObject: dataIdFromObject,
     );
     return json == null ? null : request.parseData(json);
   }
@@ -147,6 +153,7 @@ class Cache {
       variables: (request.vars as dynamic)?.toJson(),
       typePolicies: typePolicies,
       addTypename: addTypename,
+      dataIdFromObject: dataIdFromObject,
     );
     return json == null ? null : request.parseData(json);
   }
@@ -177,6 +184,7 @@ class Cache {
         data: (data as dynamic)?.toJson(),
         typePolicies: typePolicies,
         addTypename: addTypename,
+        dataIdFromObject: dataIdFromObject,
       );
 
   /// Normalizes [data] for the given fragment and writes it to the [Store].
@@ -206,6 +214,7 @@ class Cache {
         data: (data as dynamic)?.toJson(),
         typePolicies: typePolicies,
         addTypename: addTypename,
+        dataIdFromObject: dataIdFromObject,
       );
 
   void _writeData(
@@ -237,6 +246,7 @@ class Cache {
         // TODO: don't cast to dynamic
         (data as dynamic)?.toJson(),
         typePolicies: typePolicies,
+        dataIdFromObject: dataIdFromObject,
       );
 
   /// Removes the entity from the [Store] as well as from any optimistic

ferry_cache/lib/src/fragment_data_change_stream.dart

@@ -2,22 +2,23 @@ import 'package:normalize/policies.dart';
 import 'package:normalize/normalize.dart';
 import 'package:collection/collection.dart';
 import 'package:ferry_store/ferry_store.dart';
+import 'package:normalize/utils.dart';
 import 'package:rxdart/rxdart.dart';
 
 import 'package:ferry_exec/ferry_exec.dart';
 import './utils/data_for_id_stream.dart';
 
 /// Emits when the data for this fragment changes, returning a `Set` of changed IDs.
 Stream<Set<String>> fragmentDataChangeStream<TData, TVars>(
-  FragmentRequest<TData, TVars> request,
-  bool optimistic,
-  Stream<Map<OperationRequest, Map<String, Map<String, dynamic>?>>?>
-      optimisticPatchesStream,
-  Map<String, dynamic>? Function(String dataId) optimisticReader,
-  Store store,
-  Map<String, TypePolicy> typePolicies,
-  bool addTypename,
-) {
+    FragmentRequest<TData, TVars> request,
+    bool optimistic,
+    Stream<Map<OperationRequest, Map<String, Map<String, dynamic>?>>?>
+        optimisticPatchesStream,
+    Map<String, dynamic>? Function(String dataId) optimisticReader,
+    Store store,
+    Map<String, TypePolicy> typePolicies,
+    bool addTypename,
+    {DataIdResolver? dataIdFromObject}) {
   final dataIds = <String>{};
 
   denormalizeFragment(
@@ -33,6 +34,7 @@ Stream<Set<String>> fragmentDataChangeStream<TData, TVars>(
     typePolicies: typePolicies,
     addTypename: addTypename,
     returnPartialData: true,
+    dataIdFromObject: dataIdFromObject,
   );
 
   /// IDs that have changed

ferry_cache/lib/src/operation_data_change_stream.dart

@@ -11,15 +11,15 @@ import './utils/operation_root_data.dart';
 
 /// Emits when the data for this request changes, returning a `Set` of changed IDs.
 Stream<Set<String>> operationDataChangeStream<TData, TVars>(
-  OperationRequest<TData, TVars> request,
-  bool optimistic,
-  Stream<Map<OperationRequest, Map<String, Map<String, dynamic>?>>?>
-      optimisticPatchesStream,
-  Map<String, dynamic>? Function(String dataId) optimisticReader,
-  Store store,
-  Map<String, TypePolicy> typePolicies,
-  bool addTypename,
-) {
+    OperationRequest<TData, TVars> request,
+    bool optimistic,
+    Stream<Map<OperationRequest, Map<String, Map<String, dynamic>?>>?>
+        optimisticPatchesStream,
+    Map<String, dynamic>? Function(String dataId) optimisticReader,
+    Store store,
+    Map<String, TypePolicy> typePolicies,
+    bool addTypename,
+    {DataIdResolver? dataIdFromObject}) {
   final operationDefinition = getOperationDefinition(
     request.operation.document,
     request.operation.operationName,
@@ -43,6 +43,7 @@ Stream<Set<String>> operationDataChangeStream<TData, TVars>(
     typePolicies: typePolicies,
     addTypename: addTypename,
     returnPartialData: true,
+    dataIdFromObject: dataIdFromObject,
   );
 
   /// IDs that have changed

ferry_cache/test/sync_operations_test.dart

@@ -44,6 +44,20 @@ void main() {
       expect(cache.readFragment(reviewFragmentReq), equals(reviewFragmentData));
     });
 
+    test('dataIdFromObject overrides cache.identify', () {
+      final cache = Cache(dataIdFromObject: (object) => 'OVERRIDE');
+      expect(cache.identify(reviewFragmentData), equals('OVERRIDE'));
+    });
+
+    test('can read and write with a data id override', () {
+      final cache = Cache(dataIdFromObject: (object) => 'OVERRIDE');
+      cache.writeFragment(reviewFragmentReq, reviewFragmentData);
+
+      reviewFragmentReq.idFields['id'] = 'OVERRIDE';
+
+      expect(cache.readFragment(reviewFragmentReq), equals(reviewFragmentData));
+    });
+
     test('can clear cache', () {
       final cache = Cache();
 

normalize/lib/src/denormalize_fragment.dart

@@ -64,8 +64,8 @@ Map<String, dynamic>? denormalizeFragment({
 
   final dataId = resolveDataId(
     data: {
-      ...idFields,
       '__typename': fragmentDefinition.typeCondition.on.name.value,
+      ...idFields,
     },
     typePolicies: typePolicies,
     dataIdFromObject: dataIdFromObject,

normalize/test/fragments_test.dart

@@ -197,5 +197,28 @@ void main() {
         equals(normalizedMap),
       );
     });
+
+    test('Override __typename on denormalize', () {
+      final fragment = parseString('''
+        fragment user on Author {
+          id
+          name
+        }
+      ''');
+      final data = {'id': '1', 'name': 'Paul'};
+
+      final normalizedMap = {
+        'NotAuthor:1': {'id': '1', '__typename': 'Author', 'name': 'Paul'},
+      };
+
+      expect(
+        denormalizeFragment(
+          document: fragment,
+          idFields: {'id': '1', '__typename': 'NotAuthor'},
+          read: (dataId) => normalizedMap[dataId],
+        ),
+        equals(data),
+      );
+    });
   });
 }