Can I run multiple integration tests with one single config file in Flutter?

Yes, running multiple "test" files with the same "config" is possible.

In the flutter jargon, your config file is your target and your test file is your driver. Your target is always login.dart but you have the two drivers login_test.dart and login_warning.dart.

With the flutter drive command, you can specify the target as well as the driver.

So in order to run both drivers, simply execute the following commands

flutter drive --target=test_driver/login.dart --driver=test_driver/login_test.dart
flutter drive --target=test_driver/login.dart --driver=test_driver/login_warning.dart

This executes first the login_test.dart and then the login_warning.dart driver.

You can always have one main test file that you initiate, like say

flutter drive --target=test_driver/app_test.dart

Then in that call your test groups as functions, like so -

void main() {
  test1();
}
void test1() {
  group('test 1', () {});}

So with one command you get to execute all the cases mentioned in the main()