feat(devtools): Allow editing context value in Provider

[eps1lon]

Summary

Allow editing of context values for modern context types.

Test Plan

Verified locally using packages/react-devtools-shell.

master:

pr:

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[gaearon]

Can we add some tests for this?

[eps1lon]

Can we add some tests for this?

I'd love to but it wasn't clear to me where and how. In previous efforts to work on devtools no tests for the frontend were added: https://github.com/facebook/react/pull/18070/files

[stale]

This pull request has been automatically marked as stale. If this pull request is still relevant, please leave any comment (for example, "bump"), and we'll keep it open. We are sorry that we haven't been able to prioritize reviewing it yet. Your contribution is very much appreciated.

[eps1lon]

bump

[bvaughn]

@rachelnabors brought this to my attention, and I will be happy to review it– after #19774 lands. (I can handle the conflicts in this PR myself if necessary.)

[eps1lon]

(I can handle the conflicts in this PR myself if necessary.)

Does it make sense to rebase this PR on your branch at this point? Otherwise I can take care of tending to this PR after #19774 lands if I notice merge conflicts.

[bvaughn]

Up to you. I'll likely rebase my branch at least once more after I resolve the last outstanding issue or two. After that, it's up to you if you feel up for handling the merge conflicts or handing them off to me. 😄

[bvaughn]

#19774 was just merged. Would you like to fix the conflict in SelectedElement @eps1lon? Or would you like me to? (Happy either way.)

[eps1lon]

I'll take a look.

[eps1lon]

Looks like the code has completely changed. Would take me a bit longer (over the next week) so if you want to get this in earlier it's probably best if you rebase this PR.

[bvaughn]

No worries. I can take a look this afternoon.

[bvaughn]

Ah, so to clarify: Editing the context value of a modern context Provider works in master now already.

Editing the context value of a Consumer works in some cases, but not all:

• You can edit class consumers that use the legacy contextTypes API.
• You can edit class consumers that use the more recent contextType API.
• You can not edit modern <Context.Consumer> values. (This would require changes on the backend to support– we'd want to follow the pattern used for editing function component props and inject a new renderer method, and I don't think that's worth it).

Going to close this PR down since it no longer seems to be required. 😄 Thanks!

[eps1lon]

Editing the context value of a modern context Provider works in master now already.

Awesome, thanks!