Transforms your code, converting comma last to comma first.
Install with npm i rocambole-commafirst
var commafirst = require('rocambole-commafirst')
, rocambole = require('rocambole')
var source = fs.readFileSync('path/to/js/file.js').toString()
var ast = rocambole.parse(source)
commafirst.transform(ast)
ast.toString() // is your transformed source
// OR
rocambole.moonwalk(ast, commafirst)