error: The function 'MyApp' isn't defined. (undefined_function at [i_am_a_rich_man] test\widget_test.dart:16)

Question

import 'package:flutter/material.dart';

void main() { 
    runApp(MaterialApp(home: Text('Snap''Kids')));
}

Answer 1

您的根目录中应该有一个名为 test 的文件夹。当您创建新应用时，它会自动在 widget_test.dart 中为 MyApp 创建一个测试。由于您已删除 MyApp，您可能应该只删除 test/widget_test.dart.

中的文件

Answer 2

    Update your method under main() method like this-
    
    void main() {
    runApp(MyApp(home: Text('Snap''Kids')));
    }
    
    OR 
    
    Goto widget_test.dart under test directory, and update
    
    await tester.pumpWidget(MyApp());
    to
    await tester.pumpWidget(MaterialApp());

 Give correct sign if you find it working.