A cross-vendor review of the parity rework (2febbb81) found three issues; all
verified and fixed here.
1. HIGH — the native≈golden half never ran in CI, so a binding marshalling bug
could pass. The golden vectors were regenerated through the Python binding,
and only pytest (binding vs that golden) runs in CI — the native reference
tests in `python/tests/aether_parity.rs` link against the PyO3 crate and no
workflow runs them. A stable PyO3 conversion defect present at regeneration
would therefore be baked into the golden and go undetected.
Fix: a real native parity test IN the `wifi-densepose-aether` crate
(`tests/golden_parity.rs`), which is std-only and a member of the v2
workspace, so it runs under the existing `cargo test --workspace`. It
recomputes the embedding with no PyO3/marshalling and asserts it matches the
SAME committed golden within tolerance. Now native≈golden AND binding≈golden
both run in CI ⇒ binding≈native, and a binding-specific artifact in the
golden surfaces here as a native mismatch. serde_json added as a
dev-dependency only (test-only; never linked into the lib or the wheel, so
the crate stays runtime-dependency-free).
Independently proven at this commit: native output equals the committed
golden BIT-FOR-BIT (128/128 exact bits, Δ=0) for both base and loaded — the
golden is native-faithful today; this test keeps it that way.
2. MEDIUM — the Python parity helper passed non-finite output. `abs(nan - b) >
tol` is False, so an all-NaN embedding slipped through. Now every element
must be `math.isfinite` first. Proven: an all-NaN vector is rejected
("element 0 is not finite (nan)"); the Rust helpers already caught it via
`<=`.
3. LOW — a coherent shift inside the per-element tolerance could move the whole
vector undetected. Added a whole-vector cosine-similarity bound (≥ 1 - 1e-6)
alongside the per-element check.
Verified on aarch64/macOS: `test_aether` 13, full `python/tests/` suite 227
passed against a `--features sota` build; the new native test passes
(2/2) run standalone (the in-worktree `cargo test -p` only failed on an
un-checked-out submodule; ci.yml checks out submodules recursively).
Co-Authored-By: Ruflo & AQE
bc0e8fd031