text: 'use strict';
  
  test('handles undefined pkg', () => {
      jest.doMock('read-pkg-up', () => ({
          sync: () => ({}),
      }));
  
      const nodeVersion = require('./node-version');
  
      expect(nodeVersion).toEqual('10.0.0');
  });
  
  test('handles undefined engines', () => {
      jest.doMock('read-pkg-up', () => ({ sync: () => ({ package: {} }) }));
  
      const nodeVersion = require('./node-version');
  
      expect(nodeVersion).toEqual('10.0.0');
  });
  
  test('handles undefined node', () => {
      jest.doMock('read-pkg-up', () => ({
          sync: () => ({ package: { engines: { npm: '^5.0.0' } } }),
      }));
  
      const nodeVersion = require('./node-version');
  
      expect(nodeVersion).toEqual('10.0.0');
  });
  
  test('handles non-digit characters', () => {
      jest.doMock('read-pkg-up', () => ({
          sync: () => ({ package: { engines: { node: '>=10.0.0' } } }),
      }));
  
      const nodeVersion = require('./node-version');
  
      expect(nodeVersion).toEqual('10.0.0');
  });
  
  test('handles empty node', () => {
      jest.doMock('read-pkg-up', () => ({
          sync: () => ({ package: { engines: { node: '' } } }),
      }));
  
      const nodeVersion = require('./node-version');
  
      expect(nodeVersion).toEqual('10.0.0');
  });
  