Four defects surfaced by the automated review, fixed with targeted tests:
1. BaseCollection.update() default now validates that documents / metadatas /
embeddings lengths match ids, raising ValueError instead of silently
misaligning pairs or raising IndexError (base.py).
2. ChromaCollection.query() now rejects the two ambiguous input shapes up
front — neither or both of query_texts / query_embeddings, and empty input
lists — with clear ValueError messages rather than delegating to chromadb's
less-obvious errors (chroma.py).
3. QueryResult.empty() accepts embeddings_requested=True to preserve the
outer-query dimension with empty hit lists when the caller asked for
embeddings, matching the spec rule that included fields carry the outer
shape even when empty (base.py). ChromaCollection.query() threads this
through on the empty-result path (chroma.py).
4. ChromaBackend cache-freshness check now matches the semantics from
mcp_server._get_client (merged via #757) on three edge cases Copilot
called out: (a) invalidate when chroma.sqlite3 disappears while a cached
client is held, (b) treat a 0→nonzero stat transition as a change so a
cache built when the DB did not yet exist is refreshed, (c) re-stat
after PersistentClient constructs the DB lazily so freshness reflects
the post-creation state (chroma.py).
Tests: 978 passed (up from 970), 8 new tests covering the fixes.
Igor Lins e Silva
42b940d263