[ffigen] Fix bug in imported enums

pkgs/ffigen/CHANGELOG.md

@@ -9,6 +9,8 @@
   `Declarations.includeMemberSet`, `Declarations.useOriginalName`,
   `Declarations.renameWithMap`, `Declarations.useMemberOriginalName`, and
   `Declarations.renameMemberWithMap`.
+- Fix [a bug](https://github.com/dart-lang/native/issues/2761) in imported
+  NS_OPTIONS enums.
 - Fix [a bug](https://github.com/dart-lang/native/issues/2760) in the internal
   variables generated by function bindings.
 

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

@@ -235,10 +235,10 @@ class EnumClass extends BindingType with HasLocalScope {
 
   @override
   String getDartType(Context context) {
-    if (isObjCImport) {
-      return '${context.libs.prefix(objcPkgImport)}.$name';
-    } else if (style == EnumStyle.intConstants) {
+    if (style == EnumStyle.intConstants) {
       return nativeType.getDartType(context);
+    } else if (isObjCImport) {
+      return '${context.libs.prefix(objcPkgImport)}.$name';
     } else {
       return name;
     }

pkgs/ffigen/test/native_objc_test/enum_config.yaml

@@ -7,6 +7,9 @@ enums:
   include:
     - Fruit
     - CoffeeOptions
+objc-interfaces:
+  include:
+    - EnumTestInterface
 headers:
   entry-points:
     - 'enum_test.m'

pkgs/ffigen/test/native_objc_test/enum_test.dart

@@ -18,6 +18,26 @@ import 'util.dart';
 void main() {
   group('enum', () {
     setUpAll(() {
+      // TODO(https://github.com/dart-lang/native/issues/1068): Remove this.
+      DynamicLibrary.open(
+        path.join(
+          packagePathForTests,
+          '..',
+          'objective_c',
+          'test',
+          'objective_c.dylib',
+        ),
+      );
+      final dylib = File(
+        path.join(
+          packagePathForTests,
+          'test',
+          'native_objc_test',
+          'objc_test.dylib',
+        ),
+      );
+      verifySetupFile(dylib);
+      DynamicLibrary.open(dylib.absolute.path);
       generateBindingsForCoverage('enum');
     });
 
@@ -33,5 +53,22 @@ void main() {
         5,
       );
     });
+
+    test('Imported enum', () {
+      // Regression test for https://github.com/dart-lang/native/issues/2761
+      expect(
+        EnumTestInterface.useImportedNSEnum(
+          NSQualityOfService.NSQualityOfServiceUtility,
+        ),
+        17,
+      );
+      expect(
+        EnumTestInterface.useImportedNSOptions(
+          NSOrderedCollectionDifferenceCalculationOptions
+              .NSOrderedCollectionDifferenceCalculationOmitInsertedObjects,
+        ),
+        1,
+      );
+    });
   });
 }

pkgs/ffigen/test/native_objc_test/enum_test.m

@@ -2,6 +2,7 @@
 // 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 <Foundation/NSArray.h>
 #import <Foundation/NSObject.h>
 
 typedef NS_ENUM(NSInteger, Fruit) {
@@ -17,3 +18,24 @@ typedef NS_OPTIONS(NSUInteger, CoffeeOptions) {
     CoffeeOptionsSugar = 1 << 1,
     CoffeeOptionsIced  = 1 << 2,
 };
+
+@interface EnumTestInterface : NSObject {}
+
++(int32_t)useImportedNSEnum:(NSQualityOfService)x;
++(int32_t)useImportedNSOptions:
+    (NSOrderedCollectionDifferenceCalculationOptions)x;
+
+@end
+
+@implementation EnumTestInterface
+
++(int32_t)useImportedNSEnum:(NSQualityOfService)x {
+  return (int32_t)x;
+}
+
++(int32_t)useImportedNSOptions:
+    (NSOrderedCollectionDifferenceCalculationOptions)x {
+  return (int32_t)x;
+}
+
+@end