[Feature Request]: Add support react@19

[rktyt]

Description

react 19 not yet added to peerDependencies

Code of Conduct

• I agree to follow this project's Code of Conduct
• I checked the current issues for duplicate requests

[bmv437]

I noticed that when I attempted to upgrade, that the behavior of the SpaceBetween component changed. When I dug deeper, I found that this was due to the use of the react-keyed-flatten-children package that the SpaceBetween component depends on for introspecting fragments and flattening children:

https://github.com/cloudscape-design/components/blob/main/src/space-between/internal.tsx#L24-L27

Let's take this example:

<SpaceBetween>
  <div>First</div>
  {someCondition && (
    <>
      <div>Second</div>
      <div>Third</div>
    </>
  )}
</SpaceBetween>

In React 18, you'd see even spacing between all three divs.

In React 19, because react-keyed-flatten-children is no longer flattening out the children of fragments, it treats the fragment around Second and Third as one unit. This means there's space between First and the fragment, but not between Second and Third.

I've filed an issue with react-keyed-flatten-children here:
grrowl/react-keyed-flatten-children#20

[bmv437]

The issue with react-keyed-flatten-children has been fixed in version v3.1.0. Since it still maintains backwards compatibility back to React 15, it can be upgraded safely.

[CarterWilde]

Hello, I was wondering if there was an estimated completion date on this?

[johannes-weber]

Hello and thanks for reaching out! We are actively working on making Cloudscape React 19 compatible.
We cannot share any concrete ETA yet and keep this request posted once done.