How to pass arguments / parameters to the npm-script using npmExecuteScripts?

I'm trying to run the npm-script from the Jenkins pipeline via the SAP Project Piper's npmExecuteScripts:

npmExecuteScripts:
    runScripts: ["testScript"]

That works! Now, I want to pass some arguments to my script.
According to the Project Piper documentation, there is a property scriptOptions, which cares about passing arguments to the called script:

Options are passed to all runScripts calls separated by a --. ./piper npmExecuteScripts --runScripts ci-e2e --scriptOptions --tag1 will correspond to npm run ci-e2e -- --tag1

Unfortunately, I can't figure out what is the proper syntax for that command.
I've tried several combinations of using scriptOptions, e.g.:

scriptOptions: ["myArg"]
scriptOptions: ["myArg=myVal"]

and many others, but still no desired outcome!

How can I call an npm-script and pass arguments / parameters to the script using the Project Piper's npmExecuteScripts?

To solve the issue, it's important to bear in mind that in contrast to the regular argument-value mapping via the npm_config_-prefix, the SAP Project Piper scriptOptions doesn't perform a mapping and passes an array of argument-value pairs «as is» instead, and then this array can be picked up via process.argv.

The Jenkins pipeline configuration:

npmExecuteScripts:
    runScripts: ["testScript"]
    scriptOptions: ["arg1=Val1", "arg2=Val2"]

package.json:

"scripts": {
    "testScript": "node ./testScript.mjs"
}

The server-side script:

/**
 * @param {Array.<String>} args - array of console input arguments to be parsed
 */
const testScript = function testScript(args) {…}

testScript(process.argv.slice(2));

P.S. Just to compare, the regular way to pass an argument's value to the npm-script looks like:

npm run testScript --arg=Val

and the server-side script:

"testScript": "echo \"*** My argument's value: ${npm_config_arg} ***\""

The output:

*** My argument's value: Val ***

The npm-script engine performs an argument-value mapping under the hood by using the npm_config_-prefix.