[google_sign_in/google_identity_services] Clear-up documentation of callbacks in various APIs and uses of those APIs (#8029)

These APIs used to accept allowInterop'd callbacks. When the
implementation was migrated to use dart:js_interop, they were wrapped
with toJS. However, starting in 3.5, to be consistent with dart2wasm,
double-wrapping a function is an error. The documentation should be
clear that it accepts only Dart functions and uses should be cleaned up
to not use allowInterop and type the callbacks' parameter and return
value correctly.

Author: srujzs

packages/google_identity_services_web/CHANGELOG.md

@@ -1,6 +1,9 @@
-## NEXT
+## 0.3.1+5
 
 * Updates minimum supported SDK version to Flutter 3.22/Dart 3.4.
+* Cleans up documentation of callbacks in `CodeClientConfig`,
+  `TokenClientConfig`, `onGoogleLibraryLoad`, and `revoke` to indicate they only
+  accept Dart functions and not JS functions.
 
 ## 0.3.1+4
 

packages/google_identity_services_web/example/integration_test/js_interop_oauth_test.dart

@@ -26,15 +26,15 @@ void main() async {
     testWidgets('TokenClientConfig', (_) async {
       final TokenClientConfig config = TokenClientConfig(
         client_id: 'testing_1-2-3',
-        callback: (_) {},
+        callback: (TokenResponse _) {},
         scope: <String>['one', 'two', 'three'],
         include_granted_scopes: true,
         prompt: 'some-prompt',
         enable_granular_consent: true,
         login_hint: 'login-hint@example.com',
         hd: 'hd_value',
         state: 'some-state',
-        error_callback: (_) {},
+        error_callback: (GoogleIdentityServicesError? _) {},
       );
 
       final utils.ExpectConfigValueFn expectConfigValue =
@@ -79,14 +79,14 @@ void main() async {
         scope: <String>['one', 'two', 'three'],
         include_granted_scopes: true,
         redirect_uri: Uri.parse('https://www.example.com/login'),
-        callback: (_) {},
+        callback: (CodeResponse _) {},
         state: 'some-state',
         enable_granular_consent: true,
         login_hint: 'login-hint@example.com',
         hd: 'hd_value',
         ux_mode: UxMode.popup,
         select_account: true,
-        error_callback: (_) {},
+        error_callback: (GoogleIdentityServicesError? _) {},
       );
 
       final utils.ExpectConfigValueFn expectConfigValue =
@@ -110,7 +110,7 @@ void main() async {
     testWidgets('returns a tokenClient', (_) async {
       final TokenClient client = oauth2.initTokenClient(TokenClientConfig(
         client_id: 'for-tests',
-        callback: (_) {},
+        callback: (TokenResponse _) {},
         scope: <String>['some_scope', 'for_tests', 'not_real'],
       ));
 

packages/google_identity_services_web/lib/src/js_interop/google_accounts_id.dart

@@ -164,7 +164,8 @@ extension GoogleAccountsIdExtension on GoogleAccountsId {
   /// ID is the `sub` property of the [CredentialResponse.credential] payload.
   ///
   /// The optional [callback] is a function that gets called to report on the
-  /// success of the revocation call.
+  /// success of the revocation call. It must be a Dart function and not a JS
+  /// function.
   ///
   /// Method: google.accounts.id.revoke
   /// https://developers.google.com/identity/gsi/web/reference/js-reference#google.accounts.id.revoke

packages/google_identity_services_web/lib/src/js_interop/google_accounts_oauth2.dart

@@ -73,7 +73,7 @@ extension GoogleAccountsOauth2Extension on GoogleAccountsOauth2 {
   /// A valid [accessToken] is required to revoke permissions.
   ///
   /// The [done] callback is called once the revoke action is done. It must be
-  /// manually wrapped in [allowInterop] before being passed to this method.
+  /// a Dart function and not a JS function.
   ///
   /// Method: google.accounts.oauth2.revoke
   /// https://developers.google.com/identity/oauth2/web/reference/js-reference#google.accounts.oauth2.revoke
@@ -103,8 +103,7 @@ extension GoogleAccountsOauth2Extension on GoogleAccountsOauth2 {
 abstract class CodeClientConfig {
   /// Constructs a CodeClientConfig object in JavaScript.
   ///
-  /// The [callback] property must be wrapped in [allowInterop] before it's
-  /// passed to this constructor.
+  /// The [callback] property must be a Dart function and not a JS function.
   factory CodeClientConfig({
     required String client_id,
     required List<String> scope,
@@ -230,8 +229,7 @@ typedef CodeClientCallbackFn = void Function(CodeResponse response);
 abstract class TokenClientConfig {
   /// Constructs a TokenClientConfig object in JavaScript.
   ///
-  /// The [callback] property must be wrapped in [allowInterop] before it's
-  /// passed to this constructor.
+  /// The [callback] property must be a Dart function and not a JS function.
   factory TokenClientConfig({
     required String client_id,
     required TokenClientCallbackFn callback,
@@ -315,9 +313,6 @@ extension TokenClientExtension on TokenClient {
 @staticInterop
 abstract class OverridableTokenClientConfig {
   /// Constructs an OverridableTokenClientConfig object in JavaScript.
-  ///
-  /// The [callback] property must be wrapped in [allowInterop] before it's
-  /// passed to this constructor.
   factory OverridableTokenClientConfig({
     /// A list of scopes that identify the resources that your application could
     /// access on the user's behalf. These values inform the consent screen that

packages/google_identity_services_web/lib/src/js_interop/load_callback.dart

@@ -23,8 +23,7 @@ external set _onGoogleLibraryLoad(JSFunction callback);
 
 /// Method called after the Sign In With Google JavaScript library is loaded.
 ///
-/// The [callback] parameter must be manually wrapped in [allowInterop]
-/// before being set to the [onGoogleLibraryLoad] property.
+/// The [function] parameter must be a Dart function and not a JS function.
 set onGoogleLibraryLoad(VoidFn function) {
   _onGoogleLibraryLoad = function.toJS;
 }

packages/google_identity_services_web/pubspec.yaml

@@ -2,7 +2,7 @@ name: google_identity_services_web
 description: A Dart JS-interop layer for Google Identity Services. Google's new sign-in SDK for Web that supports multiple types of credentials.
 repository: https://github.com/flutter/packages/tree/main/packages/google_identity_services_web
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+google_identiy_services_web%22
-version: 0.3.1+4
+version: 0.3.1+5
 
 environment:
   sdk: ^3.4.0

packages/google_sign_in/google_sign_in_web/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.12.4+3
+
+* Fixes callback types for `TokenClientConfig`.
+
 ## 0.12.4+2
 
 * Adds support for `web: ^1.0.0`.

packages/google_sign_in/google_sign_in_web/lib/src/gis_client.dart

@@ -188,9 +188,9 @@ class GisSdkClient {
   //
   // Token clients have an additional `error_callback` for miscellaneous
   // errors, like "popup couldn't open" or "popup closed by user".
-  void _onTokenError(Object? error) {
+  void _onTokenError(GoogleIdentityServicesError? error) {
     if (error != null) {
-      _tokenResponses.addError((error as GoogleIdentityServicesError).type);
+      _tokenResponses.addError(error.type);
     }
   }
 
@@ -223,9 +223,9 @@ class GisSdkClient {
     }
   }
 
-  void _onCodeError(Object? error) {
+  void _onCodeError(GoogleIdentityServicesError? error) {
     if (error != null) {
-      _codeResponses.addError((error as GoogleIdentityServicesError).type);
+      _codeResponses.addError(error.type);
     }
   }
 

packages/google_sign_in/google_sign_in_web/pubspec.yaml

@@ -3,7 +3,7 @@ description: Flutter plugin for Google Sign-In, a secure authentication system
   for signing in with a Google account on Android, iOS and Web.
 repository: https://github.com/flutter/packages/tree/main/packages/google_sign_in/google_sign_in_web
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+google_sign_in%22
-version: 0.12.4+2
+version: 0.12.4+3
 
 environment:
   sdk: ^3.3.0