'Could not find source file at index.ios.js' when I run 'react-native bundle --minify' -

i'm trying submit react native app store. when run react-native bundle --minify root folder of project following error:

building package...  /appname/node_modules/react-native/node_modules/promise/lib/done.js:10       throw err;             ^ notfounderror: not find source file @ index.ios.js     @ /appname/node_modules/react-native/packager/react-packager/src/dependencyresolver/dependencygraph/index.js:169:15     @ trycallone (/appname/node_modules/react-native/node_modules/promise/lib/core.js:37:12)     @ /appname/node_modules/react-native/node_modules/promise/lib/core.js:103:15     @ flush (/appname/node_modules/react-native/node_modules/promise/node_modules/asap/raw.js:50:29)     @ process._tickcallback (node.js:355:11) 

i figured out. index.ios.js needs in root/main directory. had in directory created.