[in_app_purchase_storekit] Make Storekit 2 the default (#9178)

Make Storekit 2 the default. Fixes https://github.com/flutter/flutter/issues/159871

## Pre-Review Checklist

packages/in_app_purchase/in_app_purchase/CHANGELOG.md

@@ -1,5 +1,7 @@
-## NEXT
+## 3.2.2
 
+* Updates `in_app_purchase_storekit` to 0.4.0 
+* Updates README with Storekit 2 examples.
 * Updates README to indicate that Andoid SDK <21 is no longer supported.
 
 ## 3.2.1

packages/in_app_purchase/in_app_purchase/README.md

@@ -356,6 +356,14 @@ if (productDetails is AppStoreProductDetails) {
   SKProductWrapper skProduct = (productDetails as AppStoreProductDetails).skProduct;
   print(skProduct.subscriptionGroupIdentifier);
 }
+
+// With StoreKit 2
+import 'package:in_app_purchase_storekit/store_kit_2_wrappers.dart';
+
+if (productDetails is AppStoreProduct2Details) {
+   SK2Product product = (productDetails as AppStoreProduct2Details).sk2Product;
+   print(product.subscription?.subscriptionGroupID);
+}
 ```
 
 The `purchaseStream` provides objects of type `PurchaseDetails`. PurchaseDetails' provides all
@@ -377,7 +385,7 @@ if (purchaseDetails is GooglePlayPurchaseDetails) {
 }
 ```
 
-How to get the `transactionState` of a purchase in iOS:
+How to get the `transactionState` of a purchase in iOS, using the original StoreKit API:
 ```dart
 //import for AppStorePurchaseDetails
 import 'package:in_app_purchase_storekit/in_app_purchase_storekit.dart';
@@ -390,6 +398,15 @@ if (purchaseDetails is AppStorePurchaseDetails) {
 }
 ```
 
+How to get the `jsonRepresentation` of a transaction in iOS, using StoreKit 2:
+```dart
+//import for SK2TransactionWrapper
+import 'package:in_app_purchase_storekit/store_kit_2_wrappers.dart';
+
+List<SK2Transaction> transactions = await SK2Transaction.transactions();
+print(transactions[0].jsonRepresentation);
+```
+
 Please note that it is required to import `in_app_purchase_android` and/or `in_app_purchase_storekit`.
 
 ### Presenting a code redemption sheet (iOS 14)

packages/in_app_purchase/in_app_purchase/pubspec.yaml

@@ -2,7 +2,7 @@ name: in_app_purchase
 description: A Flutter plugin for in-app purchases. Exposes APIs for making in-app purchases through the App Store and Google Play.
 repository: https://github.com/flutter/packages/tree/main/packages/in_app_purchase/in_app_purchase
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+in_app_purchase%22
-version: 3.2.1
+version: 3.2.2
 
 environment:
   sdk: ^3.5.0

packages/in_app_purchase/in_app_purchase_storekit/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.4.0
+
+* **BREAKING CHANGE:** StoreKit 2 is now the default for all devices that support it.
+* To revert to StoreKit1 for devices below iOS 15, call `enableStoreKit1`
+
 ## 0.3.22+1
 
 * Fix a channel thread-safety issue when StoreKit2 is enabled.

packages/in_app_purchase/in_app_purchase_storekit/example/lib/main.dart

@@ -12,7 +12,6 @@ import 'consumable_store.dart';
 import 'example_payment_queue_delegate.dart';
 
 void main() {
-  InAppPurchaseStoreKitPlatform.enableStoreKit2();
   WidgetsFlutterBinding.ensureInitialized();
   // When using the Android plugin directly it is mandatory to register
   // the plugin as default instance as part of initializing the app.

packages/in_app_purchase/in_app_purchase_storekit/lib/src/in_app_purchase_storekit_platform.dart

@@ -31,7 +31,7 @@ class InAppPurchaseStoreKitPlatform extends InAppPurchasePlatform {
   InAppPurchaseStoreKitPlatform();
 
   /// Experimental flag for StoreKit2.
-  static bool _useStoreKit2 = false;
+  static bool _useStoreKit2 = true;
 
   /// StoreKit1
   static late SKPaymentQueueWrapper _skPaymentQueueWrapper;
@@ -251,10 +251,17 @@ class InAppPurchaseStoreKitPlatform extends InAppPurchasePlatform {
   @Deprecated('Use countryCode')
   Future<String?> getCountryCode() => countryCode();
 
-  /// Turns on StoreKit2. You cannot disable this after it is enabled.
-  /// This can only be enabled if your device supports StoreKit 2.
+  /// StoreKit 2 is now the default.
+  @Deprecated('StoreKit 2 is now the default')
   static Future<bool> enableStoreKit2() async {
-    _useStoreKit2 = await SKRequestMaker.supportsStoreKit2();
+    _useStoreKit2 = true;
+    return true;
+  }
+
+  /// Call this before `registerPlatform` to re-enable StoreKit1
+  @Deprecated('Please note that StoreKit 1 will be removed in the future.')
+  static Future<bool> enableStoreKit1() async {
+    _useStoreKit2 = !(await SKRequestMaker.supportsStoreKit2());
     return _useStoreKit2;
   }
 }

packages/in_app_purchase/in_app_purchase_storekit/lib/src/store_kit_2_wrappers/sk2_transaction_wrapper.dart

@@ -27,7 +27,8 @@ class SK2Transaction {
       required this.appAccountToken,
       this.subscriptionGroupID,
       this.price,
-      this.error});
+      this.error,
+      this.jsonRepresentation});
 
   /// The unique identifier for the transaction.
   final String id;
@@ -62,6 +63,9 @@ class SK2Transaction {
   /// Any error returned from StoreKit
   final SKError? error;
 
+  /// The json representation of a transaction
+  final String? jsonRepresentation;
+
   /// Wrapper around [Transaction.finish]
   /// https://developer.apple.com/documentation/storekit/transaction/3749694-finish
   /// Indicates to the App Store that the app delivered the purchased content
@@ -105,7 +109,8 @@ extension on SK2TransactionMessage {
         productId: productId,
         purchaseDate: purchaseDate,
         expirationDate: expirationDate,
-        appAccountToken: appAccountToken);
+        appAccountToken: appAccountToken,
+        jsonRepresentation: jsonRepresentation);
   }
 
   PurchaseDetails convertToDetails() {

packages/in_app_purchase/in_app_purchase_storekit/pubspec.yaml

@@ -2,7 +2,7 @@ name: in_app_purchase_storekit
 description: An implementation for the iOS and macOS platforms of the Flutter `in_app_purchase` plugin. This uses the StoreKit Framework.
 repository: https://github.com/flutter/packages/tree/main/packages/in_app_purchase/in_app_purchase_storekit
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+in_app_purchase%22
-version: 0.3.22+1
+version: 0.4.0
 
 environment:
   sdk: ^3.4.0

packages/in_app_purchase/in_app_purchase_storekit/test/fakes/fake_storekit_platform.dart

@@ -33,6 +33,7 @@ class FakeStoreKitPlatform implements TestInAppPurchaseApi {
   bool isPaymentQueueDelegateRegistered = false;
   String _countryCode = 'USA';
   String _countryIdentifier = 'LL';
+  bool shouldStoreKit2BeEnabled = true;
 
   void reset() {
     transactionList = <SKPaymentTransactionWrapper>[];
@@ -283,7 +284,7 @@ class FakeStoreKitPlatform implements TestInAppPurchaseApi {
 
   @override
   bool supportsStoreKit2() {
-    return true;
+    return shouldStoreKit2BeEnabled;
   }
 }
 

packages/in_app_purchase/in_app_purchase_storekit/test/in_app_purchase_storekit_2_platform_test.dart

@@ -40,7 +40,6 @@ void main() {
     InAppPurchaseStoreKitPlatform.registerPlatform();
     iapStoreKitPlatform =
         InAppPurchasePlatform.instance as InAppPurchaseStoreKitPlatform;
-    InAppPurchaseStoreKitPlatform.enableStoreKit2();
     fakeStoreKit2Platform.reset();
   });
 

packages/in_app_purchase/in_app_purchase_storekit/test/in_app_purchase_storekit_platform_test.dart

@@ -26,6 +26,7 @@ void main() {
   });
 
   setUp(() {
+    InAppPurchaseStoreKitPlatform.enableStoreKit1();
     InAppPurchaseStoreKitPlatform.registerPlatform();
     iapStoreKitPlatform =
         InAppPurchasePlatform.instance as InAppPurchaseStoreKitPlatform;