13/06/2022 1 APP010-2 -  MOBILE APPLICATIONS - PowerPoint Presentation

1. 13/06/20221APP010-2 - MOBILE APPLICATIONS Lecture 12: Testing & Plugins

2. TestingIntegration- Integration tests are written using the integration_test package (https://github.com/flutter/flutter/tree/main/packages/integration_test) , provided by the SDK. Unit The test package (https://pub.dev/packages/test) provides the core framework for writing unit testsWidgetTo test widget classes, you need a few additional tools provided by the flutter_test package (https://api.flutter.dev/flutter/flutter_test/flutter_test-library.html) , which ships with the Flutter SDK.13/06/20222

3. An introduction to integration testingCreate an app to test.Add the integration_test dependency.Create the test files.Write the integration test.Run the integration test.

4. Run the integration test.a. MobileTo test on a real iOS / Android device, first connect the device and run the following command from the root of the project:flutter test integration_test/app_test.dartOr, you can specify the directory to run all integration tests:flutter test integration_test13/06/20224

5. Run the integration test (Cont..)5b. WebTo get started testing in a web browser, Download ChromeDriver. import'package:integration_test/integration_test_driver.dart';Future<void> main() => integrationDriver();Launch WebDriver, for example:chromedriver --port=4444From the root of the project, run the following command:flutter drive \ --driver=test_driver/integration_test.dart \ --target=integration_test/app_test.dart \ -d web-server13/06/20225

6. Performance profiling (Cont..):There are two options: first, manually test the app on different devices. Alternatively, run an integration test that performs a specific task and records a performance timeline. Then, examine the results to determine whether a specific section of the app needs to be improved.In this recipe, learn how to write a test that records a performance timeline while performing a specific task and saves a summary of the results to a local file.This recipe uses the following steps:Write a test that scrolls through a list of items.Record the performance of the app.Save the results to disk.Run the test.Review the results.13/06/20226

7. 1- Write a test that scrolls through a list of items.13/06/20227To focus on performance profiling, this recipe builds on the Scrolling recipe in widget tests.2- Record the performance of the app// Example shows the reportKey is changed to scrolling_timeline.await binding.traceAction( () async { // Scroll until the item to be found appears. await tester.scrollUntilVisible( itemFinder, 500.0, scrollable: listFinder, );}, reportKey: 'scrolling_timeline',);

8. 3 - Save the results to disk13/06/20228 4 - Run the testflutter drive \ --driver=test_driver/perf_driver.dart \ --target=integration_test/scrolling_test.dart \ --profile

9. 13/06/202295 - Review the resultsscrolling_summary.timeline_summary.json contains the summary. Open the file with any text editor to review the information contained within. With a more advanced setup, you could save a summary every time the test runs and create a graph of the results.scrolling_timeline.timeline.json contains the complete timeline data. Open the file using the Chrome browser’s tracing tools found at chrome://tracing. The tracing tools provide a convenient interface for inspecting the timeline data to discover the source of a performance issue.

10. An introduction to unit testing13/06/2022101- Add the test dependencydev_dependencies: test: <latest_version>counter_app/ lib/ counter.dart test/ counter_test.dart2- Create a test file

11. 13/06/202211An introduction to unit testing (Cont…)3- Create a class to testclass Counter { int value = 0; void increment() => value++; void decrement() => value--;}4- Write a test for our class// Import the test package and Counter classimport 'package:test/test.dart';import 'package:counter_app/counter.dart';void main() { test('Counter value should be incremented', () { final counter = Counter(); counter.increment(); expect(counter.value, 1); }); }

12. 13/06/2022125. Combine multiple tests in a groupAn introduction to unit testing (Cont…)Combine them using the group function provided by the test package.6. Run the testRun tests using IntelliJ or VSCodeIntelliJOpen the counter_test.dart fileSelect the Run menuClick the Run 'tests in counter_test.dart' optionAlternatively, use the appropriate keyboard shortcut for your platform.VSCodeOpen the counter_test.dart fileSelect the Run menuClick the Start Debugging optionAlternatively, use the appropriate keyboard shortcut for your platform.

13. 13/06/202213Mock dependencies using MockitoAdd the package dependencies.Create a function to test.Create a test file with a mock http.Client.Write a test for each condition.Run the tests.For more information, see the Mockito package documentation at https://pub.dev/packages/mockito

14. An introduction to widget testingTo test widget classes, you need a few additional tools provided by the flutter_test packagehttps://api.flutter.dev/flutter/flutter_test/flutter_test-library.htmlwhich uses the following steps:Add the flutter_test dependency.Create a widget to test.Create a testWidgets test.Build the widget using the WidgetTester.Search for the widget using a Finder.Verify the widget using a Matcher.13/06/202214

15. An introduction to widget testing (Cont..)1- Add the flutter_test dependency dev_dependencies: flutter_test: sdk: flutter2- Create a widget to test3- Create a testWidgets testvoid main() {testWidgets('MyWidget has a title and message', (tester) async {});}13/06/202215

16. 13/06/2022164- Build the widget using the WidgetTestervoid main() { testWidgets('MyWidget has a title and message', (tester) async {await tester.pumpWidget(const MyWidget(title: 'T', message: 'M')); }); }5- Search for our widget using a Findervoid main() { testWidgets('MyWidget has a title and message', (tester) async { await tester.pumpWidget(const MyWidget(title: 'T', message: 'M'));final titleFinder = find.text('T'); final messageFinder = find.text('M'); });}

17. 6- Verify the widget using a Matchervoid main() { testWidgets('MyWidget has a title and message', (tester) async { await tester.pumpWidget(const MyWidget(title: 'T', message: 'M')); final titleFinder = find.text('T'); final messageFinder = find.text('M');expect(titleFinder, findsOneWidget); expect(messageFinder, findsOneWidget); });}13/06/202217An introduction to widget testing (Cont..)

18. Find widgetsTo locate widgets in a test environment, use the Finder classeshttps://api.flutter.dev/flutter/flutter_test/Finder-class.htmlusing the tools provided by the flutter_test package.https://api.flutter.dev/flutter/flutter_test/flutter_test-library.html13/06/202218