"webpack": "^4.41.0",
"webpack-cli": "^3.3.9",
"webpack-dev-server": "^3.8.1"
"copy-webpack-plugin": "^5.0.4",

package.json中的test:

    "scripts": {
        "test": "npx webpack-dev-server --config webpack.config.js"
    },

报错:

PS D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server> npm run test
Debugger attached.

> 01-webpack-introductory@1.0.0 test D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server
> npx webpack-dev-server --config webpack.config.js

Debugger attached.
Debugger attached.
Waiting for the debugger to disconnect...
D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\schema-utils\src\validateOptions.js:32
    throw new ValidationError(ajv.errors, name);
    ^

ValidationError: CopyPlugin Invalid Options

options should be array

    at validateOptions (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\schema-utils\src\validateOptions.js:32:11)
    at new CopyPlugin (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\copy-webpack-plugin\dist\index.js:26:30)
    at Object.<anonymous> (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\webpack.config.js:120:9)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at Module.require (internal/modules/cjs/loader.js:952:19)
    at require (internal/modules/cjs/helpers.js:88:18)
    at WEBPACK_OPTIONS (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\webpack-cli\bin\utils\convert-argv.js:114:13)
    at requireConfig (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\webpack-cli\bin\utils\convert-argv.js:116:6)
    at D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\webpack-cli\bin\utils\convert-argv.js:123:17
    at Array.forEach (<anonymous>)
    at module.exports (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\webpack-cli\bin\utils\convert-argv.js:121:15)
    at Object.<anonymous> (D:\Project\WebStudy\zhiboyu\webpack\24_webpack_dev_server\node_modules\webpack-dev-server\bin\webpack-dev-server.js:84:40)
    at Module._compile (internal/modules/cjs/loader.js:1063:30) {
  errors: [
    {
      keyword: 'type',
      dataPath: '',
      schemaPath: '#/type',
      params: { type: 'array' },
      message: 'should be array'
    }
  ]
}
Waiting for the debugger to disconnect...
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! 01-webpack-introductory@1.0.0 test: `npx webpack-dev-server --config webpack.config.js`npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the 01-webpack-introductory@1.0.0 test 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!     C:\Users\kirin\AppData\Roaming\npm-cache\_logs\2021-05-21T07_51_47_749Z-debug.log  
Waiting for the debugger to disconnect...

其中主要是这里(webpack.config.js出错):

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! 01-webpack-introductory@1.0.0 test: `npx webpack-dev-server --config webpack.config.js`npm ERR! Exit status 1

解决:
在webpack.config.js中下面这一段出错:

new CopyWebpackPlugin(
            {
                patterns:
                    [{ from: "./doc", to: "doc" }]
            }
        ),

修改为:

new CopyWebpackPlugin(
            [{ from: "./doc", to: "doc" }]
        ),

然后就跑成功了,