variadic positional arguments are duplicated if specified through config

[aol-nnov]

minimal example

const yargs = require('yargs/yargs');

yargs(process.argv.slice(2))
    .parserConfiguration({
        'combine-arrays': true
    })
    .config(
        {
            "sourceIdx": "source",
            "binIdx": [
                "bin1-file",
                "bin2-file"
            ]
        }
    )
    .command('$0 <packageToSeed> [sourceIdx] [binIdx..]',
        'make build sequence from a single package',
        {},
        (argv) => console.log(argv))
    .argv;

invocation: node ./minimal.js qwe

actual output:

{
  _: [],
  sourceIdx: 'source',
  binIdx: [ 'bin1-file', 'bin2-file', 'bin1-file', 'bin2-file' ],
  '$0': 'minimal.js',
  packageToSeed: 'qwe',
  'package-to-seed': 'qwe',
  'bin-idx': [ 'bin1-file', 'bin2-file' ]
}

expected output:

{
  _: [],
  sourceIdx: 'source',
  binIdx: [ 'bin1-file', 'bin2-file' ],
  '$0': 'minimal.js',
  packageToSeed: 'qwe',
  'package-to-seed': 'qwe',
  'bin-idx': [ 'bin1-file', 'bin2-file' ]
}

Can't help but notice that dashed variant of an array contains correct values.

I'm using yargs@17.3.0 and node v12.21.0

[jly36963]

Thanks for the bug report! I'll work on a fix for this

[bcoe]

@jly36963 the fix in #2100 seems to solve the issue when combine-arrays is false, but behaves a bit oddly when it's true. It seems that veriadic arguments are combined with the array defined in the config, but not arguments passed as dash arguments.

[jly36963]

@bcoe Looking now 👀