Bun: csv_data_load job stalls permanently on new-attribute upsert as non-super-user #1265

Summary

Under the Bun runtime, csv_data_load and csv_file_load jobs intermittently transition to IN_PROGRESS but never reach a terminal status. The stall appears to be a general Bun csv-job issue, not limited to a specific role or operation type.

Evidence

Instance 1 — csv_data_load as non-SU (new attribute):

• Run: 27394284006 / job 80958519370, shard 5/6 Bun
• Job ID: bef99a07-87ba-4d01-9bdc-af1d25a37019, user: bulk_load_user (non-SU restricted role)
• Payload: CSV upsert introducing a new attribute (new_attr)
• Ran full 300-second ceiling; row never written (row_count: 29)

Instance 2 — csv_file_load as admin (super-user):

• Run: 27414686473 / job 81024621348, shard 3/6 Bun
• Job ID: e784fc9e-2bd6-4fdd-aa22-ff00486d7f12, user: admin (super-user)
• Type: csv_file_load without database param
• Ran 30-second polling ceiling; job still IN_PROGRESS

Both instances: job is created, transitions to IN_PROGRESS, but never completes. Equivalent operations complete in 1–3s under Node.js. The stall is not limited to non-super-user roles or new-attribute introductions — instance 2 is admin + file load.

Hypothesis

The Bun runtime has a difference in async scheduling or I/O behavior in the csv job worker path that causes the job to hang. The specific trigger may be in the file-read or table-write pipeline when executed under Bun's event loop. Worth inspecting whether there is any await / callback / stream handling in the csv job worker that behaves differently under Bun vs Node.js.

Current workaround

The csv_data_load new-attribute upsert tests are skipped on Bun via the bunSkip pattern in #1262 with a TODO(harper#1265) pointing here. The csv_file_load test failure (instance 2) is still being assessed (flake vs. systematic).

Reproduction hint

Run the integration test suite under Bun. Any test that initiates a csv_data_load or csv_file_load job and polls for completion may trigger this stall. Monitor get_job for the resulting job entry — it should stall IN_PROGRESS.