什么是小部件测试？

Question

I just started with testing in flutter i am writing unit tests for my business logic. I am also familiar with mocking dependencies, however widget testing is quite overwhelming? In Widget testing what are we actually doing? Can someone answer this with a simple analogy

Answer 1

In Flutter I'd outline:

1. Unit testing via https://pub.dev/packages/test - Dart's standard unit testing package. It knows nothing about Flutter and Widgets. You create tests, where class instances are initialized, methods are called, instances' state is checked - a typical unit testing irrelevant to UI framework. Sounds like what you're doing.
2. Widget testing with https://api.flutter.dev/flutter/flutter_test/flutter_test-library.html - Flutters widget testing library, depebds on Dart's test. This one is used to emulate Flutter engine (ie creating MaterialApp, Widgets etc.) and iteract with virtual UI (or part of UI) of your app by clicking buttons, waiting for animations to complete and UI to refresh (via tester.pump()) etc. It is called Widget testing cause you essential test specific Widgets of your app, rather than some generic 'units' of code.
3. UI/Integration testing via https://api.flutter.dev/flutter/flutter_driver/flutter_driver-library.html - Flutter's analog to Selenium Web Driver, runs tests against a complete app running in emulator or on physycal device.