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selector in useSelector called one more time after forceUpdate inside hook

See original GitHub issue

What is the current behavior?

When state changed, selector recomputes, and value sets into latestSelectedState. Component will re-render, and selector recomputes again, but its value already in latestSelectedState.current

(selector is arrow function - const data = useSelector((state) =>;)

What is the expected behavior?

Selector recomputes once

I can open PR to fix this, but I don’t know, may be selector specially calls twice for some reasons

Issue Analytics

  • State:closed
  • Created 3 years ago
  • Reactions:1
  • Comments:9 (5 by maintainers)

github_iconTop GitHub Comments

markeriksoncommented, Apr 17, 2021

@phantomcosmonaut no, that shouldn’t have anything to do with this issue. This is about a selector re-running when the component is already rendering. What you’re describing is a store subscription causing a component to render in the first place.

If you’re seeing problems with React-Redux and Suspense, please file a new issue with a reproduction so we can look into it.

phantomcosmonautcommented, Apr 17, 2021

Hey, I was using Suspense and a custom hook to render components asynchronously with async data fetching redux actions and I seem to have run into an issue directly related to this thread. I get the error Cannot update a component ('IdentityVerificationScreen') while rendering a different component ('RenderSuspender'). To locate the bad setState() call inside 'RenderSuspender' which takes me to the forceRender call from useSelector hook. Do you think the update in 7.2.4 will solve this issue and when can I expect to see the new version released? Thanks!

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