WIP: perf: avoid re-renders caused by useEffect
#4164
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Simon-Laux
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Oct 2, 2024
| useEffect(() => { | ||
| const queryStrHasChanged = useHasChanged2(queryStr) | ||
| // TODO why don't we just call this unconditionally????? | ||
| // `Object.is()` will take care of infinite loops. |
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I assume Object.is() is part of react's implementation of setState?
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That's right https://react.dev/reference/react/useState#setstate
If the new value you provide is identical to the current state, as determined by an Object.is comparison, React will skip re-rendering the component and its children. This is an optimization. Although in some cases React may still need to call your component before skipping the children, it shouldn’t affect your code.
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not completely clear from the comment alone, better mention that this is done by setState
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Sure, this is just a rough draft
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Having read https://react.dev/learn/you-might-not-need-an-effect#adjusting-some-state-when-a-prop-changes, I think we might be overusing
useEffectto detect prop/state changes.I'm not a huge React expert, but I would like to ask if these changes make sense.