Border Radius serialized with unit set to undefined

[ockham]

Description

When setting the border radius via the slider control for any block that supports it, but not changing the default unit (px), the latter is serialized in the corresponding block attribute as undefined.

Potentially relevant PRs: #33017 #33117 cc/ @aaronrobertshaw @ntsekouras @oandregal

Also cc/ing @andrewserong @ciampo (b/c #35281) -- Is there anything we can do to catch an issue like this at compile time level (e.g. by typing potential values of the unit in UnitControl?)

Step-by-step reproduction instructions

1. Insert a block that has support for setting the border radius (Button, Group, Image, Pullquote, Search).
2. Use the sidebar control for setting the border radius, and set to an arbitrary value. Don't change the unit but leave it at its default px.
3. Switch to the code editor to inspect.

Screenshots, screen recording, code snippet

Environment info

No response

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[andrewserong]

Interesting issue, thanks for the ping @ockham! I can only recreate this if I click a single time on the RangeControl for the border radius, without sliding left or right at all. If I enter a value directly in the UnitControl, or if I slide to adjust the range control at all, then the px unit is used and updated correctly in the code editor view.

I'll do a bit more digging, but I suspect there'll be some logic we might need to update in https://github.com/wordpress/gutenberg/blob/trunk/packages/block-editor/src/components/border-radius-control

EDIT: I think this line is the culprit.

[andrewserong]

I've opened a fix in #35651

[ciampo]

typing potential values of the unit in UnitControl

Hey @ockham, if I understand correctly what you meant, @andrewserong and I discussed it in #35138 (comment) and decided to leave it as a loose string type

[ockham]

typing potential values of the unit in UnitControl

Hey @ockham, if I understand correctly what you meant, @andrewserong and I discussed it in #35138 (comment) and decided to leave it as a loose string type

Thanks @ciampo! Yeah, that's what I meant 😄 That comment makes sense. However, I wonder how an undefined value could slip through if the type is set to string? 🤔 Maybe it's accidentally converted to an 'undefined' string somewhere? 🤔

[ciampo]

Judging by the fix in #35651, could it be that the file where the bug originated from was not type-checked?

[ockham]

Judging by the fix in #35651, could it be that the file where the bug originated from was not type-checked?

Ah, quite possibly! 😅