useId: Add regression test for bottom-up passing

[eps1lon]

Summary

Passing test for #20127. Was failing with useOpaqueIdentifier.

The useId tests didn't have any test with passing the value to another component via useEffect. Im not particulary bought into this specific pattern. Mostly filing this to get clarification whether this pattern is generally supported or not.

Closes #20127

How did you test this change?

• jest

[sizebot]

Comparing: 8c4a05b...cbbf54a

Critical size changes

Includes critical production bundles, as well as any change greater than 2%:

Name	+/-	Base	Current	+/- gzip	Base gzip	Current gzip
oss-stable/react-dom/cjs/react-dom.production.min.js	=	130.01 kB	130.01 kB	=	41.55 kB	41.55 kB
oss-experimental/react-dom/cjs/react-dom.production.min.js	=	134.99 kB	134.99 kB	=	43.02 kB	43.02 kB
facebook-www/ReactDOM-prod.classic.js	=	424.29 kB	424.29 kB	=	78.28 kB	78.28 kB
facebook-www/ReactDOM-prod.modern.js	=	412.85 kB	412.85 kB	=	76.51 kB	76.51 kB
facebook-www/ReactDOMForked-prod.classic.js	=	424.29 kB	424.29 kB	=	78.28 kB	78.28 kB

Significant size changes

Includes any change greater than 0.2%:

(No significant changes)

Generated by 🚫 dangerJS against cbbf54a

[acdlite]

So this pattern isn't great for other reasons, but they're not anything to with useId itself.

The string returned from useId doesn't have any special restrictions attached to it. It's the same as a string returned from, say, useState or something, except you can't update it and React decides what the value is.

[eps1lon]

Feel free to discard and close the underlying issue. Just wanted to confirm this works now and is intended to work in the future.