babel: babel-node shouldn't pass the arguments-separator (`--`)

Input Code

Example repo: https://github.com/florianb/babelbug

console.dir(process.argv)

Babel Configuration (.babelrc, package.json, cli command)

None

Expected Behavior

Calling

babel-node index.js -- --version

should pass

[ 'node',
'/<...>/babelbug/index.js',
'--version' ]

to the called program.

Current Behavior

Calling

babel-node index.js -- --version

currently passes

[ 'node',
'/<...>/babelbug/index.js',
'--',
'--version' ]

to the called program.

Possible Solution

Increase the beginning index of the sliced userArgs (in https://github.com/babel/babel/blob/7.0/packages/babel-cli/src/babel-node.js#L17) by one:

userArgs = babelArgs.slice(argSeparator + 1); // including the  --

(The comment should, of course, be removed)

Context

I am trying to develop a command line app which is able to call other commands. In some cases i am calling commands with that command-line-tool, passing all arguments after the separator -- to the called command (i’m using minimist for that purpose).

However, i had to find out, that using babel-node just passes the first separator, too - which should separate babel-node arguments from the arguments mentioned to be consumed by my command-line application.

My command-line app now recieves the double-dash as first argument and since it is common practice to pass these arguments (following the arg-separator) to subsequent command calls, minimist puts them away for later use. Which leads to the current situation, that my application in fact doesn’t receive any dedicated arguments.

I really think the current behavior of babel-node is wrong, it should consume it’s arguments and the argument-separator and it should pass all arguments behind the separator to the executed program. So it is possible to chain calls as it is the separators intention.

I’d be happy to create a PR for that.

Your Environment

software	version
Babel	6.18.0
node	7.4.0
npm	4.3.0
Operating System	Darwin Kernel Version 15.6.0: Mon Jan 9 23:07:29 PST 2017; root:xnu-3248.60.11.2.1~1/RELEASE_X86_64 x86_64