                        课程
                    
                        /前端开发
                        
                            /前端工具
                        
                        /Grunt-beginner前端自动化工具

运行grunt-test的时候，出现错误

Running "test" task
Running "clean:server" (clean) task
>> 0 paths cleaned.
Running "concurrent:test" (concurrent) task
Running "postcss:dist" (postcss) task
Running "browserSync:test" (browserSync) task
Running "mocha:all" (mocha) task
Testing: http://localhost:9001/index.html
Warning: Cannot read property 'pid' of undefined Use --force to continue.
Aborted due to warnings.