npm run dev 报错，不太懂webpack，请大神帮忙解决。

[yandw]

npm run dev

@1.0.0 dev /Users/atom/Workspace/iview
webpack-dev-server --content-base ./ --open --inline --hot --compress --history-api-fallback --config webpack.dev.config.js

fs.js:157
throw new ERR_INVALID_CALLBACK();
^

TypeError [ERR_INVALID_CALLBACK]: Callback must be a function
at maybeCallback (fs.js:157:9)
at Object.fs.write (fs.js:674:14)
at /Users/atom/Workspace/iview/webpack.dev.config.js:10:8
at FSReqWrap.oncomplete (fs.js:169:20)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! @1.0.0 dev: webpack-dev-server --content-base ./ --open --inline --hot --compress --history-api-fallback --config webpack.dev.config.js
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the @1.0.0 dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /Users/atom/.npm/_logs/2018-05-29T01_29_12_570Z-debug.log

[BnuzLeo]

遇到一样的问题，有没有解决的方法？

[shanxiage]

参考这个才对！https://github.com/iview/iview-admin/pull/649/files

[BnuzLeo]

@shanxiage 谢谢， 我试了这样也可以。
把webpackdev.dev.config.js里面改成：

fs.open('./src/config/env.js', 'w', function(err, fd) {
const buf = 'export default "development";';
fs.write(fd, buf, 0, buf.length, function(err, written, buffer) {});
});