I'm not sure if this is the appropriate place for this, but I had a need to use form fields with names using brackets: field_name[bracket1][bracket2]. (I guess I really don't NEED this, but it sure makes handling on the server side much better organized.)

I wrote a few lines of code that take the formidable fields and breaks them into JSON objects and values. For instance formidable would pass in the above example as a field named fields.'field_name[bracket1][bracket2]', and I need to have that dealt with in the form fields.field_name.bracket1.bracket2

I don't know whether one would expect to find this code in formidable or some other location of the stack, but I have included below the code snippet I created to make this work:

let form = new formidable.IncomingForm();
form.parse(req, (err, fields, files) => {
  // Handle array inputs
  let newFields = {};
  for(let _i1 in fields) {
    let _curLoc = newFields,
         _split = _i1.split('['),
         _splitLength = _split.length - 1;
    for(let _i2 in _split) {
      let _pointer = _split[_i2].replace(']', '');
      if(_i2 == _splitLength) {
        _curLoc[_pointer] = fields[_i1]; 
      } else {
        _curLoc[_pointer] = _curLoc[_pointer] ? _curLoc[_pointer] : {};
      }
      _curLoc = _curLoc[_pointer];
    }
  }
  fields = newFields;
  // do other stuff
}