我目前的版本
node14.15.1
npm 6.16.8
cnpm 6.1.1

执行 cnpm install 总是报下面这个错误，是 npm 和 cnpm 版本兼容问题。

localhost:shuntian-pc-client lvtao0420$ cnpm install
✖ Install fail! Error: Unsupported URL Type: npm:string-width@^4.2.0
Error: Unsupported URL Type: npm:string-width@^4.2.0
    at parseUrl (/usr/local/lib/node_modules/cnpm/node_modules/npm-package-arg/npa.js:186:13)
    at npa (/usr/local/lib/node_modules/cnpm/node_modules/npm-package-arg/npa.js:79:12)
    at _install (/usr/local/lib/node_modules/cnpm/node_modules/npminstall/lib/install.js:62:11)
    at _install.next (<anonymous>)
    at onFulfilled (/usr/local/lib/node_modules/cnpm/node_modules/co/index.js:65:19)
    at /usr/local/lib/node_modules/cnpm/node_modules/co/index.js:54:5
    at new Promise (<anonymous>)
    at co (/usr/local/lib/node_modules/cnpm/node_modules/co/index.js:50:10)
    at toPromise (/usr/local/lib/node_modules/cnpm/node_modules/co/index.js:118:63)
    at next (/usr/local/lib/node_modules/cnpm/node_modules/co/index.js:99:29)

解决办法，macOS系统安装node版本管理工具n

sudo npm i -g n
sudo n 16.15.0
npm i -g cnpm
cnpm i -g cnpm

最后执行 cnpm install 成功。