Min/Max property of SpinButton has no effect when providing custom increment/decrement callbacks

[lukasbash]

Environment Information

• Package version(s): 6.213.0
• Browser and OS versions: Google Chrome 81.0.4044.92 on macOS 10.15.4

Please provide a reproduction of the bug in a codepen:

https://codepen.io/lukasbash/pen/pojPXEV?editors=1010

Actual behavior:

If the min and/or max properties are provided and onIncrement and/or onDecrement are provided, then the min/max values have no actual effect.

Expected behavior:

There are different points of view in my opinion:

• either the increment/decrement callbacks should not be called if the limit exceeds the max value (this does actually only work if step is provided)
• or the min/max value is passed to the relative handler (i.e. max to onIncrement and min to onDecrement)
• or min/max and onIncrement/onDecrement are mutually exclusive (this would actually be my favorite, because how it works now, the first properties indicate uncontrolled, and the second ones a controlled behavior).

Priorities and help requested:

Are you willing to submit a PR to fix? No

Requested priority: Normal

Products/sites affected: -

[aneeshack4]

@lukasbash Thanks for reaching out to us! So, like you said in the 3rd bullet point of expected behavior, min/max having no effect when onIncrement/onDecrement are provided is how these two patterns are mutually exclusive in practice.

[lukasbash]

@aneeshack4 Thank you for the fast response! Well, if it is intended that it works like this, then this should be clearly documented.
I think it might even make sense to strictly exclude the types via XOR (so if you pass e.g. the min and onDecrement property, it indicates an error.

[aneeshack4]

@joschect Maybe a line could be added about this to the Dos/Donts section of SpinButton's page? Besides that, @lukasbash we're currently focusing on improvements to performance and coherence, as you can see in #12770 detailing our v8 plans so while we don't plan to address this right now, when we get a chance to work on SpinButton in the future, this will be taken into consideration. Thank you for reaching out to us.

[msft-github-bot]

@joschect

Gentle ping that this issue needs attention.