[Fast Refresh] Make edits to a memo comparison function take effect - #36964
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Editing the second argument of memo() previously never took effect until something else remounted the tree, for two separate reasons: - When adding a comparison function, we need to switch from SimpleMemoComponent to MemoComponent so canPreserveStateBetween should return false. - MemoComponent was missing from the hot reload type resolution in createWorkInProgress, so existing fibers kept reading .compare from the old memo object forever. New behavior: - Adding or removing the comparison function remounts; we need to do this when adding (SimpleMemoComponent doesn't support a comparison function) so let's also do it when removing. - Editing the comparison function implementation applies in place with state preserved The TODO in isCompatibleFamilyForHotReloading is removed as that wasn't the right place to do this check.
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…36964) Editing the second argument of memo() previously never took effect until something else remounted the tree, for two separate reasons: - When adding a comparison function, we need to switch from SimpleMemoComponent to MemoComponent so canPreserveStateBetween should return false. - MemoComponent was missing from the hot reload type resolution in createWorkInProgress, so existing fibers kept reading .compare from the old memo object forever. New behavior: - Adding or removing the comparison function remounts; we need to do this when adding (SimpleMemoComponent doesn't support a comparison function) so let's also do it when removing. - Editing the comparison function implementation applies in place with state preserved The TODO in isCompatibleFamilyForHotReloading is removed as that wasn't the right place to do this check. DiffTrain build for [4400d6c](4400d6c)
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…36964) Editing the second argument of memo() previously never took effect until something else remounted the tree, for two separate reasons: - When adding a comparison function, we need to switch from SimpleMemoComponent to MemoComponent so canPreserveStateBetween should return false. - MemoComponent was missing from the hot reload type resolution in createWorkInProgress, so existing fibers kept reading .compare from the old memo object forever. New behavior: - Adding or removing the comparison function remounts; we need to do this when adding (SimpleMemoComponent doesn't support a comparison function) so let's also do it when removing. - Editing the comparison function implementation applies in place with state preserved The TODO in isCompatibleFamilyForHotReloading is removed as that wasn't the right place to do this check. DiffTrain build for [4400d6c](4400d6c)
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Editing the second argument of memo() previously never took effect
until something else remounted the tree, for two separate reasons:
SimpleMemoComponent to MemoComponent so canPreserveStateBetween
should return false.
createWorkInProgress, so existing fibers kept reading .compare from
the old memo object forever.
New behavior:
this when adding (SimpleMemoComponent doesn't support a comparison
function) so let's also do it when removing.
with state preserved
The TODO in isCompatibleFamilyForHotReloading is removed as that
wasn't the right place to do this check.