whiteshadow1234 / flutter_widget_and_unit_test

An example of how to do unit test and widget test in flutter

uTest

Steps

1. Add unit_test.dart in the test folder

2. Adjust some code from this script and paste it in unit_test.dart:

import 'package:flutter_test/flutter_test.dart';
import 'package:utest/counter.dart';

import 'package:utest/main.dart';

void main() {
  test('Counter value should be incremented', () {
    // setup the counter class
    final counter = Counter();
    //expect(counter.value, 0);
    
    // do the testing part
    counter.increment();
    
    // check if the result is expected
    expect(counter.value, 1);
  });
}

3. Create a counter.dart in the same directory where main.dart is and build up your class:

class Counter {
  int value = 0;
  void increment() {
    value++;
  }
}

4. Revise the code in main.dart with the class you just created:

//...

class _MyHomePageState extends State<MyHomePage> {
  Counter counter = Counter();

  // void _incrementCounter() {
  //   setState(() {
  //     // This call to setState tells the Flutter framework that something has
  //     // changed in this State, which causes it to rerun the build method below
  //     // so that the display can reflect the updated values. If we changed
  //     // _counter without calling setState(), then the build method would not be
  //     // called again, and so nothing would appear to happen.
  //     _counter++;
  //   });
  // }

  @override
  Widget build(BuildContext context) {
      //...

//...
        children: <Widget>[
            const Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '${counter.value}',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
//...

//...
    floatingActionButton: FloatingActionButton(
        onPressed: () {
          setState(() {
            counter.increment();
          });
        },
//...

5. Next, press the testing button in the left side in VScode and press Debug Test button

testing button	Debug Test button

Result