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10.0.0-alpha.1 - Component returned from useMemo renders when nothing has changed

See original GitHub issue

I was searching for an alternative to shouldComponentUpdate when I discovered that useMemo always executes it callback (tested with an empty array and a hard value in array).

In this codesandbox you can see the difference between React and Preact where one renders a single time and the other multiple times (output in console).

Issue Analytics

State:
Created 5 years ago
Comments:5 (5 by maintainers)

Top GitHub Comments

1reaction

vaneenigecommented, Aug 11, 2020

Great to hear, thanks Marvin! 🙌

1reaction

marvinhagemeistercommented, Aug 11, 2020

FYI: We’ve shipped the strictly equal vnode optimization earlier this year. I’m unable to reproduce the issue in the linked codesandbox when updating to the latest version of Preact 🎉

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