Error message

Running command - failed![ERROR] An error occurred while running npm install (exit code 1):

        throw err;

    Error: Cannot find module '../lib/utils/unsupported.js'
        at Function.Module._resolveFilename (module.js:469:15)
        at Function.Module._load (module.js:417:25)
        at Module.require (module.js:497:17)
        at require (internal/module.js:20:19)
        at /usr/local/lib/node_modules/npm/bin/npm-cli.js:19:21
        at Object.<anonymous> (/usr/local/lib/node_modules/npm/bin/npm-cli.js:79:3)
        at Module._compile (module.js:570:32)
        at Object.Module._extensions..js (module.js:579:10)
        at Module.load (module.js:487:32)
        at tryModuleLoad (module.js:446:12)

Try to remove /usr/local/lib/node_modules/npm and reinstall node again. This should work.

On MacOS with Homebrew:

sudo rm -rf /usr/local/lib/node_modules/npm
brew reinstall node

Other Solution –

1) Run following commands:

sudo rm -rf /usr/local/lib/node_modules/npm
brew uninstall --force node      

2) Then, proceed to Node.js Official Website to download latest package for new installation.

3) Run your npm command again, which should longer have any errors.

This method is working on macOS Mojave Version 10.14.4