add test for common.expand() and pass it
add test for common.expand() and pass it

beni55/shelljs,node-proj/shelljs,joaoafrmartins/shelljs,shelljs/shelljs,psema4/shelljs,arturadib/shelljs,rezonant/shelljs,moatazelmasry2/shizz,1000copy/shelljs,blockloop/shelljs,xebitstudios/shelljs,mcanthony/shelljs,jcoreio/shelljs,moatazelmasry2/shizz,freitagbr/shelljs,a-x-/shelljs,1000copy/shelljs,vinodpanicker/shelljs,quietshu/shelljs,joaoafrmartins/shelljs,sanemat/shelljs,zhangda89/shelljs