I'm writing a Flutter web application and I want to write a test on the behavior when the user loads the app when he types the URL in the browser's address bar.
For example I would like my test to behave as if the user typed /my/path.
How can I do that?
If you look at the class PlatformDispatcher (which olds a singleton instance .instance) you can see a getter defaultRouteName.
The route or path that the embedder requested when the application was launched.
This will be the string "
/" if no particular route was requested.
So when your user starts your application with the url /my/path, PlatformDispatcher.instance.defaultRouteName with be equal to '/my/path'.
You can also access the PlatformDispatcher.instance from WidgetsBinding.instance.platformDispatcher and if you read the doc of the getter platformDispatcher, you'll read:
A subclass of
BindingBase, such asTestWidgetsFlutterBinding, can override this accessor to return a differentui.PlatformDispatcherimplementation.
In the context of a testWidgets
testWidgets('', (WidgetTester test) async {});
tester.binding gives you access to the TestWidgetsFlutterBinding which is the binding used by widgets library tests. In this test binding, the platformDispatcher is overridden and a TestPlatformDispatcher with a setter defaultRouterNameTestValue that you can use to mock the defaultRouteName getter.
You can use:
tester.binding.platformDispatcher.defaultRouteNameTestValue = '/my/path'
to test the behavior when the user loads the app when he types the URL /my/path in the browser's address bar.