car-interface-android/test/manifest_impeller_test.dart

import 'dart:io';

import 'package:flutter_test/flutter_test.dart';

void main() {
  test('Impeller opt-out is application-scoped', () {
    final manifest = File('android/app/src/main/AndroidManifest.xml')
        .readAsStringSync();

    final applicationStart = manifest.indexOf('<application');
    final applicationEnd = manifest.indexOf('</application>');
    final activityStart = manifest.indexOf('<activity');
    final activityEnd = manifest.indexOf('</activity>');
    final impeller = manifest.indexOf(
      'io.flutter.embedding.android.EnableImpeller',
    );

    expect(applicationStart, greaterThanOrEqualTo(0));
    expect(applicationEnd, greaterThan(applicationStart));
    expect(activityStart, greaterThan(applicationStart));
    expect(activityEnd, greaterThan(activityStart));
    expect(impeller, greaterThan(applicationStart));
    expect(impeller, lessThan(applicationEnd));
    // Flutter ignores this key under <activity>; keep it out of that block.
    expect(impeller < activityStart || impeller > activityEnd, isTrue);
  });
}