Provide custom parameters ($npm_config_) to npm scripts on Windows

I have npm scripts in the package.json, I would like to provide custom parameter from the command line. I found many stackoverflow questions and answers but none of them works. I tried this solution:

  "scripts": {
    "foo": "echo $npm_config_foo && echo done"
  },

When I run the command:

$ npm run foo --foo=test

> echo $npm_config_foo && echo done

$npm_config_foo
done

As you can see, it does not echo test.

This is my configuration:

- OS: Windows
- Terminal: GitBash
- npm version: 7.14.0

I tried this, on Linux and it works. This is related to Windows.

Answer

The solution is to use % instead of $.

  "scripts": {
     "foo": "echo %npm_config_foo% && echo done",
  },