Adds the three driver commands, parameterized E11000 messages (engine
dup_index carries the index name into writeErrors), the scan_matching
planner wiring (_id fast path → index plan → scan) and the first-$match
aggregate pushdown. The equivalence test (mixed-type corpus x 27 filters,
non-sparse and sparse indexes) drove out three real bugs: the two-bound
range under-approximation on multikey indexes (fall back to scan), a
dangling single-value option array in the planner, and update-time
unique violations now reporting writeErrors instead of corrupting state.
Collection gains an indexes list; evict_doc removes entries at the single
document-death chokepoint; upsert does build → check → reserve → log →
evict → publish so entry insertion after the append is infallible and a
rejected unique write never reaches the log. Replay registers empty
indexes from create/drop records (types 3/4) and Engine.open rebuilds them
from live docs. compact re-emits index-create records. Engine gains
create_index/drop_index and dup_index for E11000 naming.
Adds src/index.zig with the full secondary-index machinery: entry
generation mirroring field_matches (array value + elements), BSON-order
sorted entries with binary search, compound prefix and range lookups,
unique/sparse options, the query planner (longest equality/$in run +
optional range, $in cartesian cap, sparse/null bail), and the _id_ fast
path guarded against serialization-ambiguous values (numbers, strings,
symbols, codes, opaque payloads).
query.collect_values is now pub so entry generation can mirror it exactly.
storage.zig gains record_type_index_create/drop; lib.zig exports index.
The Node driver sends {field: /re/} as a BSON regex element (type 0x0B),
which the matcher previously only handled via the $regex operator form;
and dot paths with numeric segments (tags.0) were ignored because array
descent only recursed into embedded docs. Both are part of standard
MongoDB query semantics and were caught by the driver e2e suite.
server: unbounded Io async limit so the accept loop never wedges, and
treat header-read failures (client RST on pool teardown) as clean
disconnects. With the default cpu_count-1 limit, groupAsync's eager
fallback ran connection handlers inline on the accept-loop fiber once
that many connections were alive, stalling accept() and timing out
handshakes for further clients.
Add tests/e2e/: official driver CRUD, concurrency, and kill -9 recovery
suites (29 + 2 + 3 checks), plus unit tests for the query fixes.
The original dispatch restructure placed the unlock defers inside switch
prongs, where Zig runs them when the prong block exits — immediately after
acquisition. All commands therefore ran with no lock at all, which the new
stress test caught deterministically (two writers inside Engine.insert at
once). Lock acquisition now happens in the prongs and the command body runs
via dispatch_impl, so the defers (still prong-scoped) release the lock only
after the command finishes.
