An introduction to widget testing - Flutter In the introduction to unit testing recipe, you learned how to test Dart classes using the test package To test widget classes, you need a few additional tools provided by the flutter_test package, which ships with the Flutter SDK The flutter_test package provides the following tools for testing widgets: The WidgetTester allows building and interacting with widgets in a test environment The
Testing Flutter apps Testing a widget involves multiple classes and requires a test environment that provides the appropriate widget lifecycle context For example, the Widget being tested should be able to receive and respond to user actions and events, perform layout, and instantiate child widgets
Tap, drag, and enter text - Flutter In the test environment, Flutter doesn't automatically rebuild widgets when the state changes To ensure that the widget tree is rebuilt after simulating a user interaction, call the pump() or pumpAndSettle() methods provided by the WidgetTester This recipe uses the following steps: Create a widget to test Enter text in the text field
Handle scrolling - Flutter How to handle scrolling in a widget test Now, you can write a test In this example, scroll through the list of items and verify that a particular item exists in the list The WidgetTester class provides the scrollUntilVisible() method, which scrolls through a list until a specific widget is visible This is useful because the height of the items in the list can change depending on the device
Find widgets - Flutter To locate widgets in a test environment, use the Finder classes While it's possible to write your own Finder classes, it's generally more convenient to locate widgets using the tools provided by the flutter_test package During a flutter run session on a widget test, you can also interactively tap parts of the screen for the Flutter tool to print the suggested Finder This recipe looks at the
An introduction to unit testing - Flutter The test package provides the core framework for writing unit tests, and the flutter_test package provides additional utilities for testing widgets This recipe demonstrates the core features provided by the test package using the following steps: Add the test or flutter_test dependency Create a test file Create a class to test
Check app functionality with an integration test - Flutter The integration_test package lets you: Use the flutter drive command to run tests on a physical device or emulator Run on Firebase Test Lab, to automate testing on a variety of devices Use flutter_test APIs to write tests in a style similar to widget tests
Testing each layer - Flutter Testing the data layer Similar to the UI layer, the components of the data layer have well-defined inputs and outputs, making both sides fake-able To write unit tests for any given repository, mock the services that it depends on The following example shows a unit test for the BookingRepository
Test orientation - Flutter This test makes sure that the orientation is landscape and that only 3 columns of data appear in the app: In test widget_test dart, inside of the Orientation group, add the following test after the landscape test: