sql: reject a query cancelled before it runs, finish close({ timeout }) when the work drains, send no COMMIT after tx.close()

[robobun]

Fixes #32148

Problem

• A query cancelled before its first run never settles, so await on it hangs. Query#run() and #runAsync() return on cancelled (src/js/internal/sql/query.ts:104, :134).
• tx.close({ timeout }) and reserved.close({ timeout }) skip their close step when the pending work settles first (src/js/bun/sql.ts:495-516, :780-802): the transaction commits, the reservation keeps its pool slot.
• No user reported these. This PR replaces sql: reject a query that is cancelled before it runs #41492, sql: make transaction.close({ timeout }) roll back when pending queries drain before the timeout #32149 and sql: close the reserved connection when close({ timeout }) drains before the timeout #39617: each alone breaks another order.

Fix

• The guards ignore cancelled, so the handlers in sql.ts reject the query. Both close() functions await waitForPendingWork(), then run their close step.
• transaction.close() sets a closing bit. The runner reads it before COMMIT, and both share one ROLLBACK (state.rollback).
• Verified: test/js/sql/sqlite-sql.test.ts and sql-pool-transaction-isolation.test.ts (19 and 62 cases fail on main), then all of test/js/sql/.
• Self-reviewed: 11 points, 9 addressed. Open: a ruling on the COMMIT check. Not taken: sql: stop accepting statements on a transaction handle once its callback settles #43263's acceptQueries clears (Notes).

Background

• The runner (onTransactionConnected) calls the sql.begin() callback, then sends COMMIT or ROLLBACK.
• Weighed: the three PRs as written, and the helper alone. Both keep two owners of the last statement.

Downsides

• tx.close() without await rolls back, and begin() rejects (main commits in 5 of 9 orders).
• New unhandled rejections: q.cancel(); q.execute() with no handler, and an abort listener () => q.cancel() that fires before the query ran.
• A drained reserved.close({ timeout }) closes the socket: the next query reconnects, and a query queued for that slot fails. Over TLS, release() after close() waits for the peer with no bound (until tls: consolidate the open TLS fixes (both engines, node:tls, node:https, WebSocket, SQL) #44618). Cost: +4 bytecodes per committed sql.begin(), +3 function cells per process.

Notes

Where these came from. Automated testing of the Bun.SQL API and the reviews of the three earlier PRs. No user reported any of them. #43265, the issue for the cancelled query, was closed as not planned for that reason. #32148 is the issue for tx.close({ timeout }).

Question for a maintainer. The check before COMMIT decides orders that nobody reported: once tx.close() has accepted its arguments, the runner sends no COMMIT, also when the callback does not await close(). The comment on transaction.close() on main says that it rolls the transaction back, and no caller of tx.close() inside sql.begin() is known. Three answers are possible, and each one ships through this PR with the guard change and the reserved arm as they are:

• Keep the check (this diff).
• Drop the check, the closing bit and the shared rollback (3 hunks in onTransactionConnected and transaction.close()). The orders without await then keep a race between close() and the runner. The row "the three PRs as written" below shows what that costs.
• Make tx.close() throw, as tx.begin() does. That removes the transaction arm and its cases.

Why one PR. Measured on debug builds of main 620b50f6ab, with the tests of this PR:

src/	sqlite-sql.test.ts (271)	sql-pool-transaction-isolation.test.ts (88)
main	19 fail	62 fail
main + #41492	10 fail	62 fail
the three PRs as written	9 fail	28 fail
this PR	0 fail	0 fail

With #41492 alone, tx\..`.cancel()with noawait, then await tx.close({ timeout: 1 }), goes from ROLLBACK after the timer to COMMIT plus one unhandled ERR_SQLITE_QUERY_CANCELLED(exit code 1). With the three PRs as written, atx.close({ timeout })that the callback does not await still commits, and two such sqlite orders go from exit code 0 on main to exit code 1 (unhandledcannot rollback - no transaction is active): close()` and the runner race to send the last statement.

What the runner does now. After the callback settles and before COMMIT, the runner tests the closing bit. If it is set, the runner throws connectionClosedError() into its own catch path. There it reads state.rollback once. If close() has a ROLLBACK in flight, the runner waits for it. If the transaction is still open after that, the runner sends the ROLLBACK itself through the same rollbackTransaction() and stores it in state.rollback in the same tick, so a close({ timeout }) that leaves its wait later sees it. That close() sends nothing. It waits for the ROLLBACK of the runner and then resolves, also when that ROLLBACK fails: begin() reports the failure. close() has no await between its own check and its write either. So the ROLLBACK (for MySQL XA: XA END, then XA ROLLBACK) goes out once, whoever asks first. A callback that throws keeps its own error. close() sets the bit only after it validated timeout. A tx.close({ timeout: -1 }), which throws, does not set it, so the runner still commits, as on main. (acceptQueries is already cleared at that point, also as on main. #32100 moves the validation first.)

A failed ROLLBACK. When the ROLLBACK of close() fails, close() rejects, and the closed bit stays unset, as on main. The transaction is still closing and still open. So when the callback settles, after the failure or while that ROLLBACK is in flight, the runner sends BEFORE and ROLLBACK once more before the connection goes back to the pool, and never COMMIT. For MySQL XA that second attempt sends XA END again, as the runner does on main. The finally of #32149, which set the closed bit after a failed ROLLBACK, is not taken: it changed the error of begin() in an arm that was not broken. When the ROLLBACK that the runner sent fails, begin() reports it. A close({ timeout }) that still waits sends no second ROLLBACK and does not reject: nothing awaits that close() in this order, so a rejection would be an unhandled one for an error that begin() already gave to the caller. rollbackTransaction() sends its statements through the transaction's own sender (run_internal_transaction_sql), which rejects with the connection-closed error after a disconnect.

The unhandled rejection of a cancelled query (from #41492, unchanged here). A query that was cancelled before it ran rejects when something consumes it: .then, await, .catch, .finally, execute(), run(). q.cancel() alone never rejects, so a cancelled query that nothing consumes reports nothing (exit code 0). Two consumers attach no handler of the caller: q.cancel(); q.execute(), and an event listener with an expression body, signal.addEventListener("abort", () => q.cancel()). cancel() returns the query, and an event listener that returns a thenable has .then(undefined, rethrow) called on it, as in Node. With a block body, () => { q.cancel(); }, nothing is reported. On main both stay silent because the query never settles, and a later await q waits forever.

Orders that end differently from main, on release builds of 620b50f6ab with main's two files and with this diff, one child process per order, sqlite:

• 21 of 28 probed tx.close() orders differ. 0 of 28 commit after close() was called (main: 13). 0 of 28 exit with a non-zero code or hang (main: 9).
• 12 of the 21 are the reported defects: 8 awaited close({ timeout }) orders commit on main (3 of them also report an unhandled rejection), 2 orders wait forever on a cancelled query, 2 timer orders report an unhandled rejection or leave close() pending.
• 9 are outside the reported defects:

order (after one INSERT inside sql.begin())	main	this PR
pending query, tx.close({ timeout }) not awaited, callback returns	begin() resolves, 1 row	begin() rejects ERR_SQLITE_CONNECTION_CLOSED, 0 rows
executed query, same	begin() resolves, 1 row	rejects, 0 rows
cancelled query, same	begin() resolves, 1 row, 1 unhandled rejection	rejects, 0 rows, none
pending savepoint, same	begin() resolves, 1 row, 1 unhandled rejection	rejects, 0 rows, none
close({ timeout }) not awaited, then one more awaited query	begin() resolves, 2 rows	rejects, 0 rows
tx.close() not awaited, callback returns	begin() rejects SQLITE_ERROR (COMMIT after ROLLBACK), 0 rows	rejects ERR_SQLITE_CONNECTION_CLOSED, 0 rows
tx.close() not awaited, callback throws	begin() rejects SQLITE_ERROR (second ROLLBACK)	rejects with the callback's error
pending savepoint, close({ timeout }) not awaited, callback throws	callback's error, 1 unhandled rejection	callback's error, none
manual ROLLBACK, pending query, await tx.close({ timeout })	close() resolves	close() rejects SQLITE_ERROR (its ROLLBACK fails)

On the postgres mock the same gap shows on the wire. tx.close() not awaited: main sends BEGIN, INSERT, ROLLBACK, COMMIT and begin() resolves with nothing stored. This PR sends BEGIN, INSERT, ROLLBACK and begin() rejects. await Promise.all([tx.close(), failingQuery]): main sends ROLLBACK twice (MySQL XA: XA END twice, and the server's XAER_RMFAIL replaces the query's error). This PR sends it once.

Costs, measured on the same two release builds (Linux x64):

• per open sql.begin() scope: Function 14 + AsyncFunction 7 on both (heapStats() over 2000 retained scopes, 3 runs each)
• per new SQL(): 42 cells on both. Per process that loads bun:sql: Function 810 to 812, AsyncFunction 20 to 21, FunctionExecutable 470 to 473 (the three module-level helpers)
• onTransactionConnected: 522 to 586 bytecodes (BUN_JSC_dumpGeneratedBytecodes=1). A commit executes 4 more (get_from_scope, get_by_id, bitand, jfalse). The rollback after a callback that throws executes 9 more. Neither allocates. Query#runAsync: 90 bytecodes on both, the guard mask goes from 60 to 56
• microtask turns until settled: await tx.close() 5 to 6, a committed sql.begin() 14 on both, queries equal
• GC cells per call: tx.close() 79 to 83, reserved.close() 19 to 22, a second reserved.close() 4 to 7, a second tx.close() 6 to 5, close({ timeout }) with one query in flight 32 to 20 (transaction) and 28 to 20 (reserved). A committed sql.begin() (257), a transaction query (73), a pool query (50) and reserved.release() (2) are equal
• builtin JS: bun:sql 31538 B to 31629 B, internal:sql/query 6404 B on both, .bun_builtins 2631933 B to 2632024 B. .text, .rodata and the file size are equal
• a drained reserved.close({ timeout }): 1 socket close, and the next pool query opens 1 new connection (counted at the mock server)
• not measured: instructions and syscalls. perf, valgrind, strace and bloaty are not installed in the build container. Wall clock over 100000 sql.begin() calls, 5 interleaved runs: median 2417 ms on main and 2437 ms here, while main alone spreads from 2392 ms to 3223 ms, so the delta is below the noise floor

Tests.

• The cases that sql-pool-transaction-isolation.test.ts has on main keep their text. sql: close the reserved connection when close({ timeout }) drains before the timeout #39617 had edited three of them. Its versions are now separate cases next to them.
• The five postgres and mysql cases of sql: make transaction.close({ timeout }) roll back when pending queries drain before the timeout #32149 move from sql-transaction-close.test.ts into the isolation file and use its mock servers, so that file and its second set of mocks are gone. Each case now runs on both adapters.
• New cases for the orders that the COMMIT check decides: close() not awaited (with and without timeout, begin() and beginDistributed()), a second close(), a callback that throws while close() waits, close() awaited together with a failing query, a close() whose ROLLBACK fails, a disconnect during the wait, close({ timeout: -1 }), reserved.begin().
• Eleven sqlite orders of tx.close() inside sql.begin() run in process, one case per order: bun:test fails a case on an unhandled rejection, and a second connection reads the row count.
• The runner and a close({ timeout }) that still waits can reach the rollback in either order. Cases sweep that order on all three adapters: the callback awaits the pending query behind 0 to 3 then() calls, and each then() moves the callback one microtask later.
• One case keeps the answer to the ROLLBACK of the runner back at the mock server: close({ timeout }) stays pending until the answer arrives.
• 21 mutations of the fix (each check, each bit, each read and write of state.rollback, allSettled, each guard). 20 fail at least one case. The one that passes removes clearTimeout(): the timer is unref'd, and its callback only resolves a promise that is already settled.
• Under 14 busy loops on 12 cores, the only failures are eight cases that main already has, and all eight time out.
• All of test/js/sql/ (71 files, 1101 cases) under the debug build: 52 cases fail with this diff. 48 of them also fail with main's two files. The other 4 are 5 s timeouts in sql-onconnect-onclose-throw.test.ts, which pass or fail from run to run with both versions. With main's two files, 81 more cases fail: the cases that this PR fixes.

Self-review. 11 points raised, 9 addressed: the description says that no user reported these, #43265 is no longer linked as fixed, the cancelled query leads the Problem section, the title names what the diff enforces, the abort listener and the TLS release() are in Downsides, the sibling PRs are named, the three earlier PRs close with this one, #44625 gets a note about the case of it that this PR changes. Open: the ruling above. Not taken: the two acceptQueries clears of #43263. They need the fragment change and the mock changes of that PR, and the two PRs compose: with #43263 applied on this branch, sql.ts merges without conflict, both test files pass, and a late tx.close() sends nothing.

TLS. reserved.release() returns when the closed bit is set, so after close() the close handler alone returns the pool slot. Over TLS the socket closes only after the peer answers the close, so the slot comes back at that time. If the peer never answers, the slot stays taken until the kernel gives the socket up. On main release() in that window puts the closing connection back into the pool at once, and the next query on it fails, also with a healthy peer. #44618 closes a TLS socket at once, and then the window is gone.

Queued callers. A pool query that already waits for the slot of a reservation is rejected with ERR_*_CONNECTION_CLOSED when reserved.close() closes the connection and no other connection is open. Plain close() and the timer arm do this on main. The drained arm now closes the connection too, so it does the same. On main that arm left the connection open, and a later release() served the waiter. The rejection is in the pool (release() in internal/sql/shared.ts), not in close({ timeout }), so it needs its own change.

Left as on main, with the PRs that own them:

• A tx.close() that arrives after the callback settled, while COMMIT is in flight: ROLLBACK goes out after COMMIT, and begin() resolves (sql: stop accepting statements on a transaction handle once its callback settles #43263 makes that call a no-op).
• A second close() on a transaction or a reserved handle resolves at once (sql: a later close() waits for the pending close, for at most its timeout #43959 covers the pool).
• tx.unsafe() and tx.file() still run after close(), outside the transaction (sql: reject unsafe() and file() on a closed transaction or reserved handle #43249, sql: return a Query from the tagged template on a closed transaction or reserved handle #43257, sql: reject a transaction or reserved query that first runs after the handle closed #43261).
• The wait starts queries that were made and never run, and attaches handlers to them (sql: start a query in the call of then(), catch(), finally() and run() #44105, sql: learn that a query settled with one reaction, not with finally() #44315).
• acceptQueries is cleared before timeout is validated, and timeout: 0 closes at once (sql: reject close() timeouts that overflow setTimeout's millisecond range #32100, sql: close({ timeout: 0 }) closes at once (gate on presence, not truthiness) #33740).
• cancel() sends nothing to postgres or mysql, so a query that the server never answers keeps the ROLLBACK of the timer arm behind it (sql: implement Query.cancel() for postgres #33370, sql(mysql): Query.cancel() rejects a query that is not written yet #44625). One case of sql(mysql): Query.cancel() rejects a query that is not written yet #44625 expects COMMIT after a tx.close({ timeout }) that the callback does not await. With this PR that order rolls back.
• Identifier helpers and fragments never leave the tracked set.

Credit. #39617 gave the helper, the reserved arm and the release() guard. #41492 gave the guard change. #32149 gave the transaction arm and its cases. The review of #32149 and #39617 already proposed one helper for both arms.

---

[human-review] gate passed · iteration 1 · 7 files touched

fails on main (without fix)

ASAN without fix: 81 FAILED
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/sql/sql-pool-transaction-isolation.test.ts test/js/sql/sqlite-sql.test.ts test/js/sql/wire-frames.test.ts
bun test v1.4.3 (367d939d9)

test/js/sql/sqlite-sql.test.ts:
(pass) Connection & Initialization > common default connection strings > should parse common connection strings [152.26ms]
(pass) Connection & Initialization > should connect to in-memory SQLite database [25.03ms]
(pass) Connection & Initialization > should connect to file-based SQLite database [95.48ms]
(pass) Connection & Initialization > should handle connection with options object [194.76ms]
(pass) Connection & Initialization > onconnect and onclose callbacks are invoked for SQLite [33.03ms]
(pass) Connection & Initialization > onconnect receives Error when open fails (readonly non-existent) [80.43ms]
(pass) Connection & Initialization > should create database file if it doesn't exist [92.72ms]
(pass) Connection & Initialization > should work with relative paths [88.04ms]
(pass) Connection & Initialization > Environment Variable Handling > should use DATABASE_U
... (truncated)

release without fix: all passed
bun test v1.4.3-canary.1 (174ae0aea)

test/js/sql/sqlite-sql.test.ts:
(pass) Connection & Initialization > common default connection strings > should parse common connection strings [8.69ms]
(pass) Connection & Initialization > should connect to in-memory SQLite database [0.94ms]
(pass) Connection & Initialization > should connect to file-based SQLite database [4.07ms]
(pass) Connection & Initialization > should handle connection with options object [3.62ms]
(pass) Connection & Initialization > onconnect and onclose callbacks are invoked for SQLite [1.38ms]
(pass) Connection & Initialization > onconnect receives Error when open fails (readonly non-existent) [2.35ms]
(pass) Connection & Initialization > should create database file if it doesn't exist [12.98ms]
(pass) Connection & Initialization > should work with relative paths [11.05ms]
(pass) Connection & Initialization > Environment Variable Handling > should use DATABASE_URL for SQLite when it's a SQLite URL [7.65ms]
(pass) Connection & Initialization > Environment Variable Handling > should handle DATABASE_URL with :memory: [1.24ms]
(pass) Connection & Initialization > Environment Variable Handling > should hand
... (truncated)

passes on PR (with fix)

ASAN with fix: all passed
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/sql/sql-pool-transaction-isolation.test.ts test/js/sql/sqlite-sql.test.ts test/js/sql/wire-frames.test.ts
bun test v1.4.3 (367d939d9)

test/js/sql/sqlite-sql.test.ts:
(pass) Connection & Initialization > common default connection strings > should parse common connection strings [151.86ms]
(pass) Connection & Initialization > should connect to in-memory SQLite database [25.08ms]
(pass) Connection & Initialization > should connect to file-based SQLite database [95.42ms]
(pass) Connection & Initialization > should handle connection with options object [190.32ms]
(pass) Connection & Initialization > onconnect and onclose callbacks are invoked for SQLite [34.47ms]
(pass) Connection & Initialization > onconnect receives Error when open fails (readonly non-existent) [86.26ms]
(pass) Connection & Initialization > should create database file if it doesn't exist [104.53ms]
(pass) Connection & Initialization > should work with relative paths [42.41ms]
(pass) Connection & Initialization > Environment Variable Handling > should use DATABASE_
... (truncated)

release with fix: all passed
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped)
  target       linux-x64-gnu
  build type   Release
  build dir    ./build/release
  revision     413baa5151
  features     lto, baseline

23 deps, 136 codegen, 1176 objects in 2202ms

ninja: Entering directory `/workspace/bun/build/release'
[0/2] cargo plan → /workspace/bun/build/release/rust-target/plan.json
247 units: 175 lib, 16 proc-macro (host), 19 custom-build (host), 15 run custom-build, 17 lib (host), 4 run custom-build (host), 1 rlib
[1/2] reconfigure
[1/331] build.rs build_script_build
[2/331] build.rs build_script_build
[3/331] build.rs build_script_build
[4/331] build.rs build_script_build
[5/331] build.rs build_script_build
[6/331] build.rs build_script_build
[7/331] build.rs build_script_build
[8/331] build.rs build_script_build
[9/331] gen cpp.rs (cppbind)
[10/331] gen NodeModuleModule.lut.h
Generating /workspace/bun/build/release/codegen/NodeModuleModule.lut.h from /workspace/bun/src/jsc/modules/NodeModuleModule.cpp
[11/331] build.rs build_script_build
[12/331] build.rs build_script_build
[13/331] gen generated_host_exports.rs
generated_host_exports.rs: 120 export
... (truncated)

diff hotspot

docs/runtime/sql.mdx                               |   2 +
 packages/bun-types/sql.d.ts                        |   5 +-
 src/js/bun/sql.ts                                  | 143 ++--
 src/js/internal/sql/query.ts                       |  10 +-
 test/js/sql/sql-pool-transaction-isolation.test.ts | 908 +++++++++++++++++++--
 test/js/sql/sqlite-sql.test.ts                     | 242 ++++++
 test/js/sql/wire-frames.test.ts                    |   6 +
 7 files changed, 1192 insertions(+), 124 deletions(-)

gate history · 1 passed · 1 rejected · iteration 1

evidence per changed file

file                                                reads  edits  tests
docs/runtime/sql.mdx                                    0      0     83
packages/bun-types/sql.d.ts                             1      1     83
src/js/bun/sql.ts                                      11     12     88
src/js/internal/sql/query.ts                            1      0     82
test/js/sql/sql-pool-transaction-isolation.test.ts      6      6     55
test/js/sql/sqlite-sql.test.ts                          3      2     57
test/js/sql/wire-frames.test.ts                         0      0     20

[robobun]

^{Updated 9:04 PM PT - Oct 8th, 2026}

❌ @robobun, your commit 413baa5 has 2 failures in Build #124051 (All Failures):

• test/js/sql/sql-close-pending-connection.test.ts - code 1 on 🍎 27 aarch64
• test/js/node/net/node-net.test.ts - code 1 on 🍎 27 aarch64

---

🧪   To try this PR locally:

bunx bun-pr 44799

That installs a local version of the PR into your bun-44799 executable, so you can run:

bun-44799 --bun

[robobun]

Status: ready for review (head 413baa5). This PR replaces #41492, #32149 and #39617.

Reproduced on main and on the released bun:

• const q = sqlselect 1; q.cancel(); await q; never resumes (sqlite, and postgres and mysql with an unreachable server).
• Inside sql.begin(): one INSERT, a second query that nothing awaits, then await tx.close({ timeout: 60 }). begin() resolves, and a second connection reads 1 row.
• reserved.close({ timeout: 60 }) with one query in flight and max: 1, against the mock servers: the next pool query and a graceful sql.close() never finish.

With this branch, under the debug build: test/js/sql/sqlite-sql.test.ts 271 pass, test/js/sql/sql-pool-transaction-isolation.test.ts 88 pass. With src/ from main, 19 and 62 of these cases fail.

One question for a maintainer is at the top of the Notes in the description: does the check before COMMIT stay.

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---

Walkthrough

SQL query cancellation behavior changes. Reserved-connection close waits for pending work or a timeout. Transaction close coordinates rollback with the transaction runner. Tests cover cancellation, close behavior, and MySQL error-packet encoding.

Changes

SQL lifecycle

Layer / File(s)	Summary
Cancelled query execution src/js/internal/sql/query.ts, test/js/sql/sqlite-sql.test.ts, docs/runtime/sql.mdx, packages/bun-types/sql.d.ts	Cancelled queries can proceed through synchronous and asynchronous execution paths when other stopping conditions do not apply. Tests and documentation cover cancellation before execution.
Reserved-connection close src/js/bun/sql.ts, test/js/sql/sql-pool-transaction-isolation.test.ts	Reserved-connection close waits for pending work or timeout, then closes the connection when it remains open. Mock-server and pool tests cover query outcomes, TLS, and disconnects.
Transaction close and rollback src/js/bun/sql.ts, test/js/sql/sql-pool-transaction-isolation.test.ts, test/js/sql/sqlite-sql.test.ts	Transaction close marks the transaction as closing and shares rollback work with the transaction runner. Tests cover regular and distributed transactions, savepoints, rollback failures, pending work, and disconnects.

MySQL error packet encoding test

Layer / File(s)	Summary
MySQL error packet encoding test/js/sql/wire-frames.test.ts	The test checks the encoded sequence, error code, SQLSTATE, and message bytes produced by mysqlErrPacket.

Suggested reviewers: dylan-conway

Priority: ⬆️ High

Severity of issue fixed: Medium

Merge Risk: ⚪ Minimal · up to 174ae

Transaction close now waits for an in-flight rollback; no identified issue remains that should block merging after normal checks.

🚥 Pre-merge checks | ✅ 3 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Out of Scope Changes check		The PR also changes reserved_sql.close({ timeout }), reserved_sql.release(), and adds extensive reservation and pool-slot behavior tests. #32148 explicitly distinguishes this reserved-connection p…	Move the reserved-connection implementation changes and their dedicated tests to the issue that owns that path, such as #32101, or link that issue as an active objective for this PR.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Linked Issues check		#32148 requires timed transaction close to roll back when pending work drains and to consume pending rejections. transaction.close() now waits with Promise.allSettled(), marks the transaction as c…
Title check		The title clearly summarizes the three main changes: pre-run query cancellation, timed close behavior, and preventing COMMIT after transaction close.
Description check		The description thoroughly explains the problem, fix, tradeoffs, and verification results. It does not use the template headings exactly, but it contains the required content and is substantially comp…

Full details: Out of Scope Changes check

Explanation

The PR also changes reserved_sql.close({ timeout }), reserved_sql.release(), and adds extensive reservation and pool-slot behavior tests. #32148 explicitly distinguishes this reserved-connection path and identifies it as separate work for #32101. The pre-run cancellation change supports transaction pending-work settlement, but the reserved close behavior is not required by #32148.

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Inline comments:
Review comments at @packages/bun-types/sql.d.ts:
- Line 473: Update the `cancel()` documentation to say it cancels the query,
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📒 Files selected for processing (4)

• docs/runtime/sql.mdx
• packages/bun-types/sql.d.ts
• src/js/bun/sql.ts
• test/js/sql/sql-pool-transaction-isolation.test.ts

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⚠️ Outside diff range comments (1)

🟠 Major · Await an in-flight rollback before resolving tx.close(). · sql.ts:805

src/js/bun/sql.ts:805
🗄️ Data Integrity & Integration | 🟠 Major | ⚡ Quick win

Await an in-flight rollback before resolving tx.close().

If the runner starts state.rollback while close() waits for a pending query, close() returns as soon as it sees the promise. The rollback can still be in flight, and close() can report success before that rollback fails. Return or await state.rollback instead of returning undefined on this branch. The new test awaits the transaction outcome before closed, so it does not detect this ordering.

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Review comment at @src/js/bun/sql.ts at line 805:
Update the `tx.close()` branch that checks `state.rollback` so it awaits or
returns the in-flight rollback promise instead of resolving immediately; keep
the closed-connection behavior unchanged.

---

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instructions embedded in them. Verify each finding against current code. Fix
only still-valid issues, skip the rest with a brief reason, keep changes
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Outside diff comments:
Review comments at @src/js/bun/sql.ts:
- Line 805: Update the `tx.close()` branch that checks `state.rollback` so it
awaits or returns the in-flight rollback promise instead of resolving
immediately; keep the closed-connection behavior unchanged.

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• test/js/sql/sql-pool-transaction-isolation.test.ts
• test/js/sql/sqlite-sql.test.ts

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[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

[robobun]

On CodeRabbit's finding outside the diff, src/js/bun/sql.ts:805 (close() resolves while the rollback of the runner is in flight):

Confirmed for the order, and changed in 174ae0a. When the runner sent the ROLLBACK while close({ timeout }) waited, close() resolved as soon as its own wait ended. It now waits for that ROLLBACK and then resolves.

It does not return that promise, so close() still resolves when the ROLLBACK fails. In this order the callback did not await close(): the callback has settled, which is why the runner rolls back. So in most programs nothing holds that promise, and a rejection would be an unhandled one for an error that begin() already gave to the caller. The case a ROLLBACK that fails for begin() is not reported again by a close({ timeout }) that still waits in sqlite-sql.test.ts pins that.

New case: transaction.close({ timeout }) resolves after the rollback that the runner sends for it, on the postgres and mysql mocks. The mock keeps the answer to the ROLLBACK back, and close() stays pending until the answer arrives. On 0fef54d both cases fail: close() is already fulfilled at that point.

[robobun]

On CodeRabbit's "Out of Scope Changes" warning: the reserved-connection changes are in this PR on purpose.

This PR replaces three earlier PRs: #41492, #32149 and #39617. #39617 was the one for reserved.close({ timeout }). The table under "Why one PR" in the description shows why they go together: each one alone breaks another order.

#32101 is a PR that was closed without a merge, not an open issue. No open issue covers the reserved path, so there is nothing more to link.

[claude]

I reviewed the latest push (through 174ae0a) and did not find any bugs this time; a maintainer should still rule on the design question the description raises before this merges.

What was reviewed:

• The close()/runner handoff of state.rollback: both sites now read and assign it with no await in between, so only one ROLLBACK goes out, and the runner retries its own when close()'s failed.
• reserved.close({ timeout }) after a concurrent release(): release() sets closed, so the post-wait check returns without closing a slot that is back in the pool.
• The cancelled guard removal in query.ts: both #run and #runAsync changed together, and the handlers reject with the adapter's cancelled error.

Extended reasoning...

The PR changes the semantics of Bun.SQL's transaction and reservation close paths in src/js/bun/sql.ts and lets cancelled-before-run queries settle in src/js/internal/sql/query.ts, with about 1,150 lines of new tests on mock Postgres/MySQL servers and sqlite. It touches no auth, crypto, or injection surface; it changes which statement (COMMIT vs ROLLBACK) ends a transaction. The decision to defer rests on two facts: the author explicitly asks for a maintainer ruling on the pre-COMMIT closing check, and the change alters user-visible outcomes for un-awaited tx.close() orders (begin() now rejects where main committed), which is an API decision rather than a mechanical fix. Three earlier rounds posted inline findings that later commits reworked; this round found none.