fix(native): one resolved-style cache key per distinct input set - #1
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`generateStateHash` keys the resolved-style cache on weak-key identity, so it shares only when equal inputs arrive as one object. Three defects break that. **The config is minted per instance.** `styled()` derives it once at module scope; `useCssElement` derives one per instance from a module constant — same value, fresh identity, so N identical elements each hold their own entry, sorted rule array and observable. `getRuleVariation`'s rule clone is keyed on that identity too, so it was per element rather than per mapping. Deriving through `weakFamily` keys the config on the mapping. A mapping that is not an object is refused by name rather than through the `Invalid value used as weak map key` a primitive would otherwise raise from inside `reactivity`; the predicate is narrower than that WeakMap contract, since a function is a valid weak key and still not a mapping. **`family` and `weakFamily` cache on truthiness.** A factory returning `0` is re-run on every lookup, and `hashKeyFamily` hands out `hashKeyCount++` — so the first weak key hashed never settles. Of twelve call sites it is the only one whose result can be falsy, so caching on presence changes nothing else. **The key is lossy.** Folding N numbers into one and printing it base-36 is a digest, and `family` returns the entry it holds while ignoring the rules the second caller brought — so a collision renders one element's styles on another. Over one config plus one rule, the commonest shape, the fold collides 31.99% of the time. Sorting and joining is exact and keeps order-independence. The numbers are collected into a `Float64Array` so the sort is native: ordering them with `Array.prototype.sort` needs a comparator, and that callback is most of what ordering costs on Hermes — 1.10x the fold at the median key count against 1.64x. Float64 rather than Int32 because the key counter is unbounded and an int32 wraps silently at 2^31. Two inherited lines go with the fold: `generateStateHash`'s empty-string sentinel — unreachable, and collidable once the key is a join — together with the two parameters no caller passes, and the loop's `if (!key) continue`, which erased a member from a value whose whole point is that it erases nothing. `family` gains `size()` so the invariant is assertable. It reaches `rootVariables` and `universalVariables`, which are `family` instances published through `./native-internal` — additive, beside the `delete` and `clear` already on them. 50 identical elements: 50 entries before, 1 after. A 150-control screen on a physical Android device: 1785 → 270-271. Re-entering a screen grew the cache without limit (2, 4, 6 …) and is now flat; entries are still never released on unmount, which is a separate defect. 19 tests across five files, each red first.
YevheniiKotyrlo
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Base layer of a stack. The submission is upstream: nativewind#434 — review and comment there.
This PR exists so the layer above it (#2) shows only its own six commits instead of seven. Nothing is merged in this fork.