Reduce unnecessary calls to useSelector selector #1804
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Currently, useSelector(selector) will call the passed selector twice on mount when it only needs to be called once on mount. This is unnecessary, and in the case of expensive selectors, can be a performance concern.
By checking if the store state has differed prior to recalculating a selector, we can avoid unnecessary selector recalculation in most cases for components on mount.
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Looks great! Let's do this. (There's a very good chance this will get immediately replaced as I try migrating over to the new |
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This change is intended to fix #1801 on the 8.x line
By checking if the store state has differed prior to recalculating a selector, we can avoid unnecessary selector recalculation in most cases for components on mount.