myip.dart

class MyIp {
  Injector get _injector => Injector.getInjector();
  Client get _client => _injector.get<Client>();

  Future<String> get ipAddress async {
    final apiResult = await _client.get('https://api.ipify.org/?format=json');
    return json.decode(apiResult.body)['ip'];
  }
}

// Testing

void main() {
  setUpAll(() {
    final injector = Injector.getInjector();
    final fakeClient = MockClient((_) async =>
      Response(json.encode({"ip": "192.168.0.1"}), 200)
    );
    
    injector.map((i) => fakeClient);
  });

  test('it returns stubbed ip', () async {
    final ipAddress = await MyIp().ipAddress;
    expect(ipAddress, '192.168.0.1');
  });
}