jaspr comes with its own testing package jaspr_test.

It is built as a layer on top of package:test and has a similar api to flutter_test.


To get started, add the package as a dev dependency to your project:

dart pub add jaspr_test --dev

A simple component test looks like this:

// This also exports 'package:test' so no need for an additional import.
import 'package:jaspr_test/jaspr_test.dart';

// Import the components that you want to test.
import 'my_component.dart';

void main() {
  group('simple component test', () {
    testComponents('renders my component', (tester) async {
      // We want to test the MyComponent component.
      // Assume this shows a count and a button to increase it.
      await tester.pumpComponent(MyComponent());

      // Should render a [Text] component with content 'Count: 0'.
      expect(find.text('Count: 0'), findsOneComponent);

      // Searches for the <button> element and simulates a click event.
      await tester.click(find.tag('button'));

      // Should render a [Text] component with content 'Count: 1'.
      expect(find.text('Count: 1'), findsOneComponent);


Since jaspr is a fullstack-framework, there are 3 test functions to choose from:

  • testComponents can unit-test components in a simulated testing environment.

    Use as shown above, by invoking testComponents and providing a component using tester.pumpComponent().

    See here for a full api reference.

  • testBrowser can test components and dom-interactions in a headless browser environment.

    Use similar to the testComponents with additional options for the url and initialStateData to simulate synced state from the server.

    See here for a full api reference.

  • testServer can test the rendering of components in a simulated server environment.

    This spins up a virtual http server where you can send requests and test the server-rendered response for your components.

    See here for a full api reference.

For more examples on how to use the testing package, check out the tests in the jaspr package.