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…g the variable (#36732) A counter initialized before a memo scope and incremented inside it (`a++` or `a = a + 1` in a `for` body) was emitted as a scope *dependency*, compared at its pre-loop value (constant every render) while the cache stored its post-loop value. The memo could never hit, so the scope recomputed on every render. Root cause: the phi-union rule in `InferReactiveScopeVariables.findDisjointMutableValues` only unioned a phi into the scope when the phi value was mutated after creation, which range-extension only does for object mutation. Primitive reassignments around a loop back-edge never extend ranges, so the counter's SSA versions stayed outside the scope and downstream dependency propagation classified the pre-loop read as a dep. The fix unions a phi with its operands and declaration when any operand is defined at or after the phi's block, i.e. the value is reassigned around a loop back-edge. This matches the shape the compiler already produced for non-primitive loop reassignment (`x = [...x, i]`). Implemented identically in the TypeScript compiler and the Rust port. Both `a++` and `a = a + 1` variants are pinned by fixtures; the first commit documents the previously-wrong codegen, the second fixes it (counter becomes a scope output, dep on `count` only). Corpus delta beyond the new fixtures is 4 fixtures, all strict improvements with byte-identical eval output: `for-in-statement-break`, `for-in-statement-continue`, `for-in-statement-type-inference` (loops previously re-ran every render, now memoized), and `sequence-expression` (two memo blocks collapse into one). Known limitation, unchanged from before: conditional reassignment in a loop (`for (...) { if (c) a++; }`) routes through a join phi that this rule cannot see; that shape behaves as it did before this change. Verification: TS snap 1806/1806, Rust snap 1806/1806, cargo workspace green, scoped TS-vs-Rust HIR parity harness green. Closes #34971
## Summary
Dependency maintenance for the Rust compiler crates.
### Fast Refresh hash: sha2 + hmac → hmac-sha256
The Fast Refresh source hash (`enableResetCacheOnSourceFileChanges`)
only needs an HMAC-SHA256 of the source text, matching the TS compiler's
`createHmac('sha256', code).digest('hex')`. RustCrypto's `sha2` + `hmac`
pulled in **11 crates** (`sha2`, `hmac`, `digest`, `block-buffer`,
`typenum`, `crypto-common`, `hybrid-array`, `const-oid`, `cpufeatures`,
`cmov`, `ctutils`) — generic-hashing / constant-time machinery that is
irrelevant for a non-security content fingerprint. This replaces them
with the single **zero-dependency** `hmac-sha256` crate: a net reduction
of **10 crates**.
HMAC-SHA256 is a standardized deterministic algorithm, so the emitted
hash is unchanged. A new unit test
`source_file_hash_matches_node_create_hmac` pins the result against
Node's `createHmac('sha256', code).digest('hex')` for several inputs.
### Other bumps
- `napi` / `napi-derive` 2 → 3
- `similar` 2 → 3 (dev-dependency)
- Drop the unused `react_compiler_lowering` dependency from
`react_compiler_ssa`
`cargo check --workspace --all-targets` passes, including the napi 3
native crate.
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