记录一个vue项目报错UnhandledPromiseRejectionWarning:Unhandledpromiserejection.

使用vue-cli创建vue项目，加入一些之前的代码，然后打包运行报错：

(node:4892) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing insi
de of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejectionid: 1)
(node:4892) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejectionsthat are not handled will terminate the Node.js process with a non-zero exit code.// 然后加卡在这里不动了
18% building modules 72/73 modules 1 active ...ce-demo\weixin-vioce-demo\src\App.vue


网上查阅了很多的资料，下面是我整理的解决方案：

1. 在build文件夹下找到webpack.base.conf.js
   然后修改加入const vueLoaderPlugin = require(‘vue-loader/lib/plugin’)

&＃39;use strict&＃39;
const path = require(&＃39;path&＃39;)
const utils = require(&＃39;./utils&＃39;)
const config = require(&＃39;../config&＃39;)
const vueLoaderConfig = require(&＃39;./vue-loader.conf&＃39;)
//加入的
const vueLoaderPlugin = require(&＃39;vue-loader/lib/plugin&＃39;)


2. 在module.exports中引入 plugins:[new vueLoaderPlugin()]

plugins:[new vueLoaderPlugin()]


3. 下面是我的文件的完整代码

&＃39;use strict&＃39;
const path = require(&＃39;path&＃39;)
const utils = require(&＃39;./utils&＃39;)
const config = require(&＃39;../config&＃39;)
const vueLoaderConfig = require(&＃39;./vue-loader.conf&＃39;)
const vueLoaderPlugin = require(&＃39;vue-loader/lib/plugin&＃39;)function resolve (dir) {return path.join(__dirname, &＃39;..&＃39;, dir)
}
module.exports = {context: path.resolve(__dirname, &＃39;../&＃39;),entry: {app: &＃39;./src/main.js&＃39;},output: {path: config.build.assetsRoot,filename: &＃39;[name].js&＃39;,publicPath: process.env.NODE_ENV === &＃39;production&＃39;? config.build.assetsPublicPath: config.dev.assetsPublicPath},resolve: {extensions: [&＃39;.js&＃39;, &＃39;.vue&＃39;, &＃39;.json&＃39;],alias: {&＃39;vue$&＃39;: &＃39;vue/dist/vue.esm.js&＃39;,&＃39;@&＃39;: resolve(&＃39;src&＃39;),}},module: {rules: [{test: /\.vue$/,loader: &＃39;vue-loader&＃39;,options: vueLoaderConfig},{ test: /\.js$/,loader: &＃39;babel-loader&＃39;,include: [resolve(&＃39;src&＃39;), resolve(&＃39;test&＃39;), resolve(&＃39;node_modules/webpack-dev-server/client&＃39;)]},{test: /\.(png|jpe?g|gif|svg)(\?.*)?$/,loader: &＃39;url-loader&＃39;,options: {limit: 10000,name: utils.assetsPath(&＃39;img/[name].[hash:7].[ext]&＃39;)}},{test: /\.(mp4|webm|ogg|mp3|wav|flac|aac)(\?.*)?$/,loader: &＃39;url-loader&＃39;,options: {limit: 10000,name: utils.assetsPath(&＃39;media/[name].[hash:7].[ext]&＃39;)}},{test: /\.(woff2?|eot|ttf|otf)(\?.*)?$/,loader: &＃39;url-loader&＃39;,options: {limit: 10000,name: utils.assetsPath(&＃39;fonts/[name].[hash:7].[ext]&＃39;)}},{test: /\.sass$/,loaders: [&＃39;style&＃39;, &＃39;css&＃39;, &＃39;sass&＃39;]},{test:/\.style$/,use:[&＃39;style-loader&＃39;,&＃39;css-loader&＃39;]}]},node: {// prevent webpack from injecting useless setImmediate polyfill because Vue// source contains it (although only uses it if it&＃39;s native).setImmediate: false,// prevent webpack from injecting mocks to Node native modules// that does not make sense for the clientdgram: &＃39;empty&＃39;,fs: &＃39;empty&＃39;,net: &＃39;empty&＃39;,tls: &＃39;empty&＃39;,child_process: &＃39;empty&＃39;},plugins:[new vueLoaderPlugin()]
}


当以上解决之后再运行项目一般来说已经可以了，但是我这个项目还不行，继续其他错误

$ webpack-dev-server --inline --progress --config build/webpack.dev.conf.js
internal/modules/cjs/loader.js:638throw err; ^
Error: Cannot find module &＃39;vue-loader/lib/plugin&＃39;at Function.Module._resolveFilename (internal/modules/cjs/loader.js:636:15)at Function.Module._load (internal/modules/cjs/loader.js:562:25)at Module.require (internal/modules/cjs/loader.js:690:17) at require (internal/modules/cjs/helpers.js:25:18)at Object.<anonymous> (D:\HBuilderProjects\baidu-vioce-demo\weixin-vioce-demo\build\webpack.base.conf.js:6:25)at Module._compile (internal/modules/cjs/loader.js:776:30)at Object.Module._extensions..js (internal/modules/cjs/loader.js:787:10)at Module.load (internal/modules/cjs/loader.js:653:32)at tryModuleLoad (internal/modules/cjs/loader.js:593:12)at Function.Module._load (internal/modules/cjs/loader.js:585:3)


这种错误其实网上有很多解决方法
主要的就是将对应的版本更新一下，就是对应的vue-loader这个插件的lib下面没有对应的plugin文件，具体做法：
升级了一下 “vue-loader”: “^15.7.0” 就好了

真棒！！