在终端执行webpack调用webpack.config.js 时，报错

在终端执行webpack调用webpack.config.js 时，报错，求大佬解决

这是我 webpack.config.js 的代码

const path = require('path')

module.exports = {
    entry: './src/main.js',
    output: {
        path: path.join(__dirname, './dist'),
        filename: 'bundle.js'
    },
    mode: 'development'
}

这是我 package.json 的内容

{
  "name": "webpack-b",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "jquery": "^3.3.1",
    "webpack": "^4.20.2",
    "webpack-cli": "^3.1.2"
  }
}

这是目录结构

这是我报错的信息

但是如果我在package.json的 script 中加上

"scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "dev": "webpack --mode development ./src/main.js --output ./dist/bundle.js"
  },

然后在终端执行 npm run dev，却是成功的，求解

package.json 里面的main改为： "main": "main.js",

package.json 里面的main改为： "main": "main.js",还是不行哦

webpack配置文件失效，待解决