Let data-show-time turn time off as well as on

[Fivell]

Follow-up to #13, which made show_time element-scoped. This fixes the half that was never reachable before that landed.

The bug

if (typeof $this.data('show-time') != 'undefined' && $this.data('show-time').toString() == 'true') {
  el_opts.show_time = true;
}

The attribute is write-only. The guard reads it, compares to "true", and assigns true. There is no branch that assigns false. So data-show-time can only ever add time, never remove it.

That matters as soon as show_time is on at a level above the element — either $.fn.date_range_ext_preset.defaults.show_time = true, which the README documents, or passed to the call:

$('.filter_date_range').date_range_ext_preset({ show_time: true });

Every matched input now gets datetimes, and data-show-time="false" on one of them is a no-op. There is no way to opt out.

This was latent until #13: before it, show_time was shared across the whole call anyway, so one element could not have differed from another regardless.

The fix

Make the attribute authoritative in both directions when it is present:

if (typeof $this.data('show-time') != 'undefined') {
  el_opts.show_time = $this.data('show-time').toString() == 'true';
}

Absent attribute still inherits from the call and the defaults, so nothing that worked before changes.

The spec

The fixture gains an input wrapped in manual_preset_pair rather than datetime_preset_pair, so the plugin's auto-init leaves it alone and the example can call the plugin with { show_time: true } without a second "Set range" link getting in the way.

On the parent commit:

expected: "2026-10-02"
     got: "2026-10-02 00:00:00"