Can't iterate a range in reverse order

[EvHaus]

I want to iterate over a date range from latest to earliest date, but this doesn't seem to work:

var start = moment("2011-11-27", "YYYY-MM-DD");
var end   = moment("2011-04-15", "YYYY-MM-DD");
var range = moment().range(start, end);
range.by('days', function (day) {
    // Never get's called. :(
    console.log(day)
});

[mickdelaney]

+1

[gf3]

how would you feel if moment-range automatically re-arranged your range so that start was always the min and end was always the max?

[EvHaus]

@gf3 I'm not sure how that would help with my issue.

[gf3]

@globexdesigns well it would always iterate the correct amount, just not in the reverse order

[atran]

+1

[NGMarmaduke]

+1

[nnnnathann]

+1

[yozef]

+1
@gf3 Maybe we can add an additional parameter

var start = moment("2011-11-27", "YYYY-MM-DD");
var end   = moment("2011-04-15", "YYYY-MM-DD");
var range = moment().range(start, end);
range.by('d', function (moment) {
   console.log(moment)
}, true, true); // last Param: true is the order in reverse, false would be searching as is now, forward.

Modifying the lib to the below would work:

// line 214
DateRange.prototype.by = function(range, hollaback, exclusive, reverse) {
  if (typeof range === 'string') {
    _byString.call(this, range, hollaback, exclusive); // not needed for my case
  }
  else {
    _byRange.call(this, range, hollaback, exclusive, reverse);
  }
  return this;
};

// then on line 248
function _byRange(interval, hollaback, exclusive, reverse) {
  var div = this / interval;
  var l = Math.floor(div);

  if (l === Infinity) { return; }
  if (l === div && exclusive) {
    l--;
  }

  if (!reverse) {
      for (var i = 0; i <= l; i++) {
        hollaback.call(this, moment(this.start.valueOf() + interval.valueOf() * i));
      }
  } else { // Loops backwards?
      for (var i = l; i >= 0; i--) {
        hollaback.call(this, moment(this.end.valueOf() - interval.valueOf() * i));
      }
  }

}

[gf3]

adding discrete methods for reverse iteration in v3, you can follow the progress here: https://github.com/gf3/moment-range/tree/3-dev

example usage here

thanks for your patience everyone

[gf3]

just opened a PR for 3.0.0 which incorporates these changes. feel free to leave feedback or raise any questions you may have. thanks again for your contributions