webpack-dev-server打包報錯

"build": "webpack --config build/webpack.config.js",
"start": "webpack-dev-server --open"
使用npm run build不報錯，但是用npm run start報錯，不知道為什么

webpack.config.js的配置

const path = require("path");
const rm = require("rimraf");
const HtmlWebpackPlugin = require("html-webpack-plugin");
//刪除文件
rm("../dist/static", err => {
  if (err) throw err;
});
module.exports = {
  context: path.resolve(__dirname, "../"),
  entry: "./src/index.js", //入口文件
  output: {
    filename: "[name].js",
    path: path.resolve(__dirname, "../dist")
  },
  devtool: "inline-source-map",
  devServer: {
    contentBase: path.resolve(__dirname, "../dist")
  },
  module: {
    rules: [
      {
        test: /\.css$/,
        use: [
          "style-loader",
          { loader: "css-loader", options: { importLoaders: 1 } },
          {
            loader: "postcss-loader",
            options: {
              plugins: loader => [
                require("autoprefixer")({ browsers: "last 2 versions" })
              ]
            }
          }
        ] //cssloader解析css,styleloader創(chuàng)建style標簽
      },
      //圖片文件
      {
        test: /\.(png|jpg|gif)$/,
        use: [
          {
            loader: "file-loader", //替換url
            options: {
              name: "[name][hash].[ext]"
            }
          }
        ]
      },
      //字體文件
      {
        test: /\.(woff|woff2|eot|ttf|otf)$/,
        use: ["file-loader"]
      }
    ]
  },
  plugins: [
    new HtmlWebpackPlugin({
      template: "index.html"
    })
  ]
};