Update package:objective_c to be compatible with ffigen

.github/workflows/objective_c.yaml

@@ -31,7 +31,6 @@ jobs:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332
       - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1
         with:
-          flutter-version: 3.19.0
           channel: 'stable'
       - id: install
         name: Install dependencies
@@ -53,7 +52,6 @@ jobs:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332
       - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1
         with:
-          flutter-version: 3.19.0
           channel: 'stable'
       - name: Install dependencies
         run: flutter pub get
@@ -90,7 +88,6 @@ jobs:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332
       - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1
         with:
-          flutter-version: 3.19.0
           channel: 'stable'
       - name: Install dependencies
         run: flutter pub get

pkgs/ffigen/lib/src/code_generator/objc_built_in_functions.dart

@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'package:meta/meta.dart';
+
 import '../code_generator.dart';
 import '../config_provider/config_types.dart';
 
@@ -43,7 +45,8 @@ class ObjCBuiltInFunctions {
       ObjCImport('UnimplementedOptionalMethodException');
 
   // Keep in sync with pkgs/objective_c/ffigen_objc.yaml.
-  static const _builtInInterfaces = {
+  @visibleForTesting
+  static const builtInInterfaces = {
     'DartProxy',
     'DartProxyBuilder',
     'NSArray',
@@ -78,11 +81,13 @@ class ObjCBuiltInFunctions {
     'NSValue',
     'Protocol',
   };
-  static const _builtInCompounds = {
+  @visibleForTesting
+  static const builtInCompounds = {
     'NSFastEnumerationState': 'NSFastEnumerationState',
     '_NSRange': 'NSRange',
   };
-  static const _builtInEnums = {
+  @visibleForTesting
+  static const builtInEnums = {
     'NSBinarySearchingOptions',
     'NSComparisonResult',
     'NSDataBase64DecodingOptions',
@@ -110,11 +115,11 @@ class ObjCBuiltInFunctions {
   // TODO(https://github.com/dart-lang/native/issues/1173): Ideally this check
   // would be based on more than just the name.
   bool isBuiltInInterface(String name) =>
-      !generateForPackageObjectiveC && _builtInInterfaces.contains(name);
+      !generateForPackageObjectiveC && builtInInterfaces.contains(name);
   String? getBuiltInCompoundName(String name) =>
-      generateForPackageObjectiveC ? null : _builtInCompounds[name];
+      generateForPackageObjectiveC ? null : builtInCompounds[name];
   bool isBuiltInEnum(String name) =>
-      !generateForPackageObjectiveC && _builtInEnums.contains(name);
+      !generateForPackageObjectiveC && builtInEnums.contains(name);
   bool isNSObject(String name) => name == 'NSObject';
 
   // We need to load a separate instance of objc_msgSend for each signature. If

pkgs/ffigen/pubspec.yaml

@@ -24,6 +24,7 @@ dependencies:
   file: ^7.0.0
   glob: ^2.0.0
   logging: ^1.0.0
+  meta: ^1.11.0
   package_config: ^2.1.0
   path: ^1.8.0
   pub_semver: ^2.1.4
@@ -37,7 +38,6 @@ dev_dependencies:
   dart_flutter_team_lints: ^2.0.0
   json_schema: ^5.1.1
   leak_tracker: ^10.0.7
-  meta: ^1.11.0
   objective_c: ^2.1.0
   test: ^1.16.2
 

pkgs/objective_c/CHANGELOG.md

@@ -4,6 +4,10 @@
   bindings if an optional method is invoked, and the instance doesn't implement
   the method.
 - Dispatch all object/block releases to the main thread.
+- Require Dart 3.4 or later (due to the use of `dart:ffi`
+  `Struct.create` by `package:ffigen`).
+- __Breaking change__: Return structs from ObjC methods by value instead of
+  taking a struct return pointer.
 
 ## 2.0.0
 

pkgs/objective_c/ffigen_objc.yaml

@@ -100,5 +100,3 @@ preamble: |
   // ignore_for_file: unused_element
   // ignore_for_file: unused_field
   // coverage:ignore-file
-
-  import 'package:ffi/ffi.dart' as pkg_ffi;