Recreate unkeyed functional components when they change position. #4550
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JoviDeCroock
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With keyed children we can confidently track them as they move throughout an array of components. When this happens with unkeyed functional components we should not risk reusing the state as that could possibly make us re-use state in unrelated components, as seen in #2949.
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With keyed children we can confidently track them as they move throughout an array of components. When this happens with unkeyed functional components we should not risk reusing the state as that could possibly make us re-use state in unrelated components, as seen in #2949.
With skew based diffing we can be sure that we account for offsets in our children arrays so this change should be quite safe.
Prior to this change we could have cases where
We'd reuse the component state from the first instance for the second one which is dangerous, we should always recreate unkeyed children.
Now there are exceptions to this, imagine we insert a
<div />in front of this then we want<Component="x" />to retain its state, thanks to our skew based diffing that will be the case.Fixes #2949
Supersedes #2955