es7 新特性

1. npx babel-upgrade --write 覆盖 preset-stage-0 配置

2. babel 安装

   {
     "@babel/core": "^7.0.0",
     "@babel/plugin-proposal-class-properties": "^7.0.0",
     "@babel/plugin-proposal-decorators": "^7.0.0",
     "@babel/plugin-proposal-do-expressions": "^7.0.0",
     "@babel/plugin-proposal-export-default-from": "^7.0.0",
     "@babel/plugin-proposal-export-namespace-from": "^7.0.0",
     "@babel/plugin-proposal-function-bind": "^7.0.0",
     "@babel/plugin-proposal-function-sent": "^7.0.0",
     "@babel/plugin-proposal-json-strings": "^7.0.0",
     "@babel/plugin-proposal-logical-assignment-operators": "^7.0.0",
     "@babel/plugin-proposal-nullish-coalescing-operator": "^7.0.0",
     "@babel/plugin-proposal-numeric-separator": "^7.0.0",
     "@babel/plugin-proposal-optional-chaining": "^7.0.0",
     "@babel/plugin-proposal-pipeline-operator": "^7.0.0",
     "@babel/plugin-proposal-throw-expressions": "^7.0.0",
     "@babel/plugin-syntax-dynamic-import": "^7.0.0",
     "@babel/plugin-syntax-import-meta": "^7.0.0",
     "@babel/plugin-transform-runtime": "^7.3.4",
     "@babel/polyfill": "^7.2.5",
     "@babel/preset-env": "^7.3.4",
     "@babel/register": "^7.0.0",
     "@babel/runtime": "^7.3.4"
   }
   

3. .babelrc 配置

   {
     "presets": [
       [
         "@babel/preset-env",
         {
           "targets": {
             "node": "current"
           }
         }
       ]
     ],
     "plugins": [
       "@babel/plugin-transform-runtime",
       "@babel/plugin-syntax-dynamic-import",
       "@babel/plugin-syntax-import-meta",
       "@babel/plugin-proposal-class-properties",
       "@babel/plugin-proposal-json-strings",
       [
         "@babel/plugin-proposal-decorators",
         {
           "legacy": true
         }
       ],
       "@babel/plugin-proposal-function-sent",
       "@babel/plugin-proposal-export-namespace-from",
       "@babel/plugin-proposal-numeric-separator",
       "@babel/plugin-proposal-throw-expressions",
       "@babel/plugin-proposal-export-default-from",
       "@babel/plugin-proposal-logical-assignment-operators",
       "@babel/plugin-proposal-optional-chaining",
       [
         "@babel/plugin-proposal-pipeline-operator",
         {
           "proposal": "minimal"
         }
       ],
       "@babel/plugin-proposal-nullish-coalescing-operator",
       "@babel/plugin-proposal-do-expressions",
       "@babel/plugin-proposal-function-bind"
     ]
   }