app_test.dart

//this code belongs to https://fluttercompletereference.com/
//Chapter 16: Test Driver
//******************************************************************************

  import 'package:flutter_driver/flutter_driver.dart';
  import 'package:test/test.dart';

  void main() {
    group("Counter app test", () {
      final counterText = find.byValueKey("counter");
      final incrementButton = find.byValueKey("increment");
      final decrementButton = find.byValueKey("decrement");

      late final FlutterDriver driver;

      setUpAll(() async {
        driver = await FlutterDriver.connect();
      });

      tearDownAll(() async {
        driver.close();
      });

      test("Counter increment", () async {
        await driver.tap(incrementButton);

        final readText = await driver.getText(counterText);
        expect(readText, "1");
      });

      test("Counter increment", () async {
        await driver.tap(decrementButton);

        final readText = await driver.getText(counterText);
        expect(readText, "0");
      });
    });
  }