V5 beta: duplicated queries on mount

[fzaninotto]

What you were expecting:
useGetOne and useGetList only trigger one call to the API.

What happened instead:
They call the API twice

Steps to reproduce:

1. Launch the simple example
2. Go to a comment edit page
3. The getOne and getList calls are doubled.

Note that the duplication disappears when I remove StrictMode. However, the example is using React 18, so this isn't caused by changes in strict mode in React 19. When using react-admin v4 with React 18, the bug doesn't appear, so this a regression introduced by v5.

Related code:

https://stackblitz.com/github/marmelab/react-admin/tree/next/examples/simple

Environment

• React-admin version: 5.0.0-beta.3
• Last version that did not exhibit the issue (if applicable): 4.16
• React version: 18
• Browser: Chrome

[djhi]

It looks like this is the expected behavior when combining react 18 strict mode and query cancellation. See TanStack/query#3633 (comment)

[fzaninotto]

I can confirm that by removing the signal in useGetOne, the getOne request is no longer duplicated. But this is very surprising: the demo uses ra-data-fakerest, which doesn't implement the abortSignal.

All in all, it means that all apps, whatever their data provider, will see duplicated queries in strict mode by default. The developer experience is worse in general, for an end user benefit that only occurs in a minority of cases.

We need to disable the abortsignal by default, and find a way to make it an opt-in feature.