anchor.diff:  import 'package:client_data/package_api.dart';
   
   import 'package:pub_dev/account/backend.dart';
  -import 'package:pub_dev/account/models.dart';
   import 'package:pub_dev/audit/backend.dart';
   import 'package:pub_dev/audit/models.dart';
   import 'package:pub_dev/fake/backend/fake_email_sender.dart';
   import 'package:pub_dev/package/backend.dart';
  -import 'package:pub_dev/package/models.dart';
   import 'package:pub_dev/shared/exceptions.dart';
   
   import '../shared/test_models.dart';
  
positive.code:         });
        });
  
        Future<void> testAlreadyExists(
            String pkg, List<User> uploaders, String newUploader) async {
          final bundle = generateBundle(pkg, ['1.0.0'], uploaders: uploaders);
          await dbService.commit(inserts: [
            bundle.package,
            ...bundle.versions,
            ...bundle.infos,
            ...bundle.assets,
          ]);
          final rs = packageBackend.inviteUploader(
              pkg, InviteUploaderRequest(email: newUploader));
          await expectLater(
              rs,
              throwsA(isA<InvalidInputException>().having((e) => '$e', 'text',
                  'InvalidInput(400): `hans@juergen.com` is already an uploader.')));
          final list = await dbService.lookup<Package>([bundle.package.key]);
          final p = list.single;
          expect(p.uploaders, uploaders.map((u) => u.userId));
        }
  
        testWithServices('already exists', () async {
          registerAuthenticatedUser(hansUser);
          final ucEmail = 'Hans@Juergen.Com';
          await testAlreadyExists('p1', [hansUser], hansUser.email);
          await testAlreadyExists('p2', [hansUser], ucEmail);
          await testAlreadyExists('p3', [hansUser, joeUser], ucEmail);
          await testAlreadyExists('p4', [joeUser, hansUser], ucEmail);
        });
  
        testWithProfile('successful', fn: () async {
  
negative.code:         });
        });
  
        testWithProfile('already exists', fn: () async {
          await accountBackend.withBearerToken(adminAtPubDevAuthToken, () async {
            Future<void> verify(String email) async {
              await packageBackend.addUploader('oxygen', email);
              final p = await packageBackend.lookupPackage('oxygen');
              final emails = await accountBackend.getEmailsOfUserIds(p.uploaders);
              expect(emails.toSet(), {'admin@pub.dev'});
            }
  
            await verify('admin@pub.dev');
            await verify('Admin@Pub.Dev');
          });
        });
  
        testWithProfile('successful', fn: () async {
  