immerjs / immer / 29524878876

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fix: draft relocated base refs after reverse/sort in array-methods plugin (#1255)

With enableArrayMethods(), reverse() and sort() run natively on copy_,
which still holds raw base references. Reordering relocates an un-drafted
base object to an index where it no longer equals base_[prop], so the get
trap's positional check misses it and returns the raw base object. Writing
to that object mutates the user's base state, violating immer's guarantee
that the base state is never modified. Patches and inverse patches are
wrong too.

Detect a relocated base reference in the get trap (only after a reorder,
for indices the user did not explicitly assign) and draft it before
exposing it.

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