Slider handler, wrapped as react component, value updates with offset by 1 when clicking on negative step

[altras]

Hello!
I hope this issue finds you joyful :)

What should happen?

I'm expecting my reactified slider handle to move where the user has clicked, all the times.

What happens instead?

The slider handle is correctly setting it's value when clicking on positive numbers. But when clicking on negative the e.target.firstChild.attributes.getNamedItem('aria-valuenow').value from $('.slider').on('changed.zf.slider)' event is having an offset by 1 :/

Possible Solution

I wanted to use some method to update the handler value again when consuming the event $('.slider').on('changed.zf.slider). Something like https://github.com/zurb/foundation-sites/blob/develop/js/foundation.slider.js#L341 but this is not working and it seems like a workaround rather than a fix.

    $('.slider').on('changed.zf.slider', e => {
      let sliderVal = parseInt(
        e.target.firstChild.attributes.getNamedItem('aria-valuenow').value,
        10,
      )
      if (sliderVal < 0) {
        sliderVal -= 1
        $('.slider').foundation('_setValues', jQuery('.slider'), sliderVal)
      }
    })

Any ideas what may be causing this problem? Or how to use the internal _setValues method to properly update the value when clicking on negative step?

Test Case and/or Steps to Reproduce

Test Case:

I've tried to recreate the issue in codepen https://codepen.io/altras/pen/oyKPJG?editors=0010 It's using our css for styling but even without it it behaves the same.

Context

We want to include the slider in a journey
to map users pleasantness and energy. But when using mouse clicking behavior the slider is not updating properly if we want to select a negative step.

Your Environment

• Foundation version(s) used: 6.4.3 foundation.min.js
• Browser(s) name and version(s):
  • Chrome Version 67.0.3396.99 (Official Build) (64-bit)
  • Firefox Quantum 61.0.1 (64-bit)
• Operating System and version (desktop or mobile): MacOS 10.13.4 (17E202)

Checklist (all required):

• I have read and follow the CONTRIBUTING.md document.
• There are no other issues similar to this one.
• The issue title is descriptive.
• The template is correctly filled.

[altras]

Hmmmm, even dragging is not working properly. Negative values are handled with an offset

[altras]

@ncoden Any forecasts when v6.5.0.rc-3 is coming out with this ? :D