I reported this in tickets section for ace3 a while back. But hasn't been fixed.
Using the latest version downloaded. When you set a stepping value for ranged. It will get ignored and you'll get floating point values as you change the value of the slider with the mouse.
Once you stop sliding it rounds to the nearest stepping value.
Also the treeview if it has a scrollbar, and you drag the scroller down it will throw an error. But works fine if you use scrollwheel. Both of these bugs I opened a ticket for.
This is on the PTR. I tested this by only enabling my addon that uses the newest version. So no other older copies of the same lib get loaded.
Well, since this doesn't happen with my own slider widgets, I'd have to say AceGUI could be improved. If the slider has a step value of 1, for instance, it should be "smart" enough to round whatever value the underlying widget reports to the nearest integer before displaying that value in the GUI or passing it to the addon that "owns" the widget.
I'm not sure what "feels odd" about rounding the value yourself when the underlying Blizzard widget incorrectly provides a value that doesn't conform to the desired stepping. If the slider's step value is set to 1, it seems more "odd" to show users a value like 2.97 instead of just rounding it to 3 before displaying it or passing it off to callbacks. I've done this in my private slider widget library for years, as "not rounding to the step value while dragging" isn't a new behavior of the Blizzard slider widget. It's only really noticable in custom sliders, though, since the base Blizzard slider template doesn't actually display the value. I've noticed it for years in the "fade delay" and "fade duration" sliders in Bazooka's main config panel, for example.
I'm not sure what "feels odd" about rounding the value yourself when the underlying Blizzard widget incorrectly provides a value that doesn't conform to the desired stepping.
What feels odd is that the slider selection lets you position it between two step values, instead of the selection jumping between those possible values as you would expect (and like it does on Live for me with ACD)
Of course the Blizzard widget behavior "feels odd" -- it's a bug, and that's my whole point. Instead of sitting back and going "well, that's odd, idk what's up with that!", I'm saying you should just add a couple lines of code to work around it in your addon/library code so that the end result -- what users see and use -- doesn't "feel odd". Not sure how I can express that idea any more clearly, so if it's still unclear, I guess I give up...