[coverage] Conformance findings: STATEMENT-025

tests/ 配下の coverage PR diff にある STATEMENT-025 xfail テストから始め、ドライバーの操作ごとの CloseOperation teardown パスを追跡します。2 クエリのケースを再現し、その後、close の失敗が teardown の外に伝播せず、接続の再利用も妨げないことを確認します。同時に、期待される行数とプロトコル呼び出しが引き続き成立することも確認します。

Summary

Surfaced by the multi-language coverage fan-out while conformance-testing these SPEC-IDs against databricks/databricks-sql-nodejs. Each finding is committed as an expected-failure (xfail) test in the coverage PR — the test asserts the CORRECT (post-fix) behavior and stays red until THIS driver (databricks/databricks-sql-nodejs) is fixed, then flips green as a tripwire.

Findings

• STATEMENT-025 [thrift]: Thrift: a failed per-operation teardown close (CloseOperation forced to 404) is not best-effort — the 404 propagates out of teardown as a raw THTTPException instead of being swallowed, so cleanup becomes a caller-visible error
  • failing test: STATEMENT-025 — failed teardown CloseOperation is swallowed and teardown continues [thrift] (see the coverage PR diff under tests/)

Reproduce & Expected

STATEMENT-025 — Validates that a FAILING per-operation close RPC issued during teardown is BEST EFFORT: the failure must not propagate out of close/dispose, and must not abort the rest of teardown.

Reproduce:

SELECT id FROM range(1000)
SELECT 1

Expected (per the shared spec):

• result has exactly 1000 row(s)
• completes without an exception
• completes without an exception
• result has exactly 1 row(s)
• full assertion contract:

result:
- label: consumed
  row_count: 1000
- label: teardown
  no_exception: true
- label: reused_connection
  no_exception: true
- label: reused_connection
  row_count: 1
protocol:
  thrift:
  - call_min:
      method: CloseOperation
      min: 1
  sea:
  - call_min:
      operation: CloseStatement
      min: 1

Context

• The behavior was first fixed in a DIFFERENT driver — reference PR: https://github.com/adbc-drivers/databricks/pull/618 — which seeded the shared language-neutral spec. This issue tracks the same conformance gap in databricks/databricks-sql-nodejs; the reference PR is for cross-referencing the intended behavior, NOT a change to this repo.
• Coverage PR carrying the reproducing xfail test(s): https://github.com/databricks/databricks-driver-test/pull/1225