安装了appium 1.9.1后一直报错Fatal TypeError: Class constructor BaseDriver cannot be invoked without ‘new‘，无法启动，卸载后安装1.8.1可以正常使用了。
npm install -g cnpm --registry=https://registry.npm.taobao.org cnpm uninstall -g appium cnpm install -g appium@1.8.1 rm /usr/local/bin/appium ln -s /usr/local/Cellar/node/10.12.0/lib/node_modules/appium/build/lib/main.js /usr/local/bin/appium
yang$ appium [Appium] Welcome to Appium v1.8.1 [Appium] Appium REST http interface listener started on 0.0.0.0:4723
之前安装的1.9.0 1.9.1都报错，无法启动：
[appium@1.9.1] link /usr/local/Cellar/node/10.12.0/bin/appium@ -> /usr/local/Cellar/node/10.12.0/lib/node_modules/appium/build/lib/main.js
yang$ /usr/local/Cellar/node/10.12.0/lib/node_modules/appium/build/lib/main.js
(node:9164) [DEP0005] DeprecationWarning: Buffer() is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead.
[Appium] Welcome to Appium v1.9.1
Fatal TypeError: Class constructor BaseDriver cannot be invoked without ‘new‘
at new AppiumDriver (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/lib/appium.js:131:19)
at main$ (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/lib/main.js:124:16)
at tryCatch (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/node_modules/_babel-runtime@5.8.24@babel-runtime/regenerator/runtime.js:67:40)
at GeneratorFunctionPrototype.invoke [as _invoke] (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/node_modules/_babel-runtime@5.8.24@babel-runtime/regenerator/runtime.js:315:22)
at GeneratorFunctionPrototype.prototype.(anonymous function) [as next] (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/node_modules/_babel-runtime@5.8.24@babel-runtime/regenerator/runtime.js:100:21)
at GeneratorFunctionPrototype.invoke (/usr/local/Cellar/node/10.12.0/lib/node_modules/appium/node_modules/_babel-runtime@5.8.24@babel-runtime/regenerator/runtime.js:136:37)
yang$ cnpm uninstall -g appium
Appium 1.9.1 启动报错 Fatal TypeError: Class constructor BaseDriver cannot be invoked without 'new'
原文：https://www.cnblogs.com/v5captain/p/9823569.html