React-admin: Unhandled rejection (HttpError) on Edit, optimistic rendering - undoable true

[sspread]

What you were expecting:
Optimistically return to index page, show error notification 'not found' once server responds with 404

What happened instead:
Optimistically returns to index page with 'undo' option as expected. But once server responds with 404, I get unhandled rejection.

Other information:
If I use undoable: false on my Edit component, the index view is not optimistically rendered and react admin correctly handles the HttpError with a 'not found' notification.

I'm using fetchUtils.fetchJson and returning a promise from update method on dataProvider. Per docs, I'm under the impression that react admin should handle http errors, and the fact that it does when undoable: false is evidence that I have it set up correctly.

Is the unhandled rejection that I'm seeing with the optimistic rendering the expected behavior for react admin?

Environment

• React-admin version: 3.11.0
• React version: 17.0.1
• Browser: chrome (latest)

[fzaninotto]

I don't understand your test case. Can you please provide a CodeSandbox reproducing the error, and add a step-by-step way to reproduce the error?

[sspread]

The test case is simply that using the out-of-the-box edit action (with undoable: true) will throw an uncaught http error after it optimistically redirects back to list view when server responds to the put/patch with an error. I can do a sandbox at some point.

[fzaninotto]

Right, it can be triggered in the simple example sandbox by editing a post, setting 'f00bar' as the title, saving, and waiting until the notification disappears.

It seems to be caused by the following line: https://github.com/marmelab/react-admin/blob/4847dc6b47a72253cc9f657e0d172dcc7c75bb0c/packages/ra-core/src/dataProvider/useDataProvider.ts#L409

It was introduced in #4291, where I used the same code for optimistic and non-optimistic calls. If it make sense to re-throw the error in non-optimistic mode (so that the dataProvider promise rejects), it doesn't make sense in optimistic mode, as the dataProvider promise already resolved. So the error musn't be rethrown in optimistic mode.