node:tls: shut the wrapped stream down when a client-side TLSSocket wrap ends or is destroyed

[robobun]

Problem

• new tls.TLSSocket(stream) without isServer, then end() or destroySoon(), kills the process: TypeError: socket.shutdown is not a function. (In 'socket.shutdown()', 'socket.shutdown' is undefined) at endNT (node:net), thrown from a nextTick. Bun 1.4.2 did nothing. Unreleased regression from tls: end() and destroySoon() before the handshake completes now send the FIN #42181, found by a fuzz run.
• This wrap keeps the wrapped stream as _handle until connect() upgrades it (src/js/node/tls.ts:834). TLSSocket.prototype._final used to park on the handshake, which never starts here. Since tls: end() and destroySoon() before the handshake completes now send the FIN #42181 it reaches endNT (src/js/node/net.ts:385), which calls _handle.shutdown(). A JS stream has none.

Fix

• _final ends the wrapped stream with stream.end(cb), as node's JSStreamSocket.doShutdown does. A wrapped net.Socket that is not connected yet waits for its 'connect' first, as in node.
• closeSocketHandle destroys a handle that is a stream, as JSStreamSocket.doClose does. The destroy() that destroySoon() issues on 'finish' threw handle.close is not a function here. Supersedes node:tls: handle destroy() on a TLSSocket wrapping an unconnected stream #35842, with instanceof Duplex for typeof close: an http2 stream has its own close(code, callback).
• The wrap closes when its stream closes, as node's _wrapHandle does. That ends an end() that waits on a refused connection, and closes the wrap once the peer answers the FIN.
• Verified: test/js/node/tls/node-tls-connect.test.ts, 7 new tests (21 cells) that run the same fixture on node v26.3.0 with the same expected report. All 7 fail on main with the TypeError. Also vendored test-tls-*, test-https-*, test-http2-*, test-net-*, test/js/node/tls/, test/js/node/net/.

Background

• _final is the shutdown hook of the writable side. 'finish' follows its callback. destroySoon() is end() plus destroy() on 'finish'.
• _handle is normally a native socket with shutdown() and close(). Only the client-side wrap holds a JS stream there (node:tls: make client-side new TLSSocket(socket) upgrade the socket it wraps #37664 changes that).
• Node puts such a stream in a JSStreamSocket. Its doShutdown calls stream.end(), its doClose calls stream.destroy().

Notes

Reproduction (no certificates needed), from the report:

const net = require("net"), tls = require("tls");
const how = process.argv[2] || "end";
const srv = net.createServer(c => { c.on("data", () => {}); c.on("end", () => console.log("peer: got FIN")); c.on("error", () => {}); });
srv.listen(0, "127.0.0.1", () => {
  const raw = net.connect(srv.address().port, "127.0.0.1", () => {
    const s = new tls.TLSSocket(raw, { rejectUnauthorized: false });
    s.on("error", e => console.log("tls 'error':", e.code || e.message));
    s.on("finish", () => console.log("tls 'finish'"));
    s.on("close", () => console.log("tls 'close'"));
    setTimeout(() => { console.log("calling", how + "()"); how === "end" ? s.end() : s.destroySoon(); }, 50);
    setTimeout(() => { console.log("exit: destroyed=" + s.destroyed, "writableFinished=" + s.writableFinished); process.exit(0); }, 500);
  });
});

call	node v26.3.0	bun 1.4.2	main (97c191b)	this branch
end()	finish, FIN, close, destroyed=true	nothing	uncaught TypeError, exit 1	same as node
destroySoon()	finish, FIN, close, destroyed=true	nothing	uncaught TypeError, exit 1	same as node

Measured again after the rebase onto main f385d9a: main still throws in both modes, the 7 new tests fail there with the TypeError, and they pass on this branch.

Twelve cells throw on main: a connected, a connecting, and a never-connected net.Socket, and a user Duplex, each with end(), end(cb), and destroySoon(). With this branch all twelve match node in the 'finish', 'error' and 'close' events of the TLS socket.

What the first five new tests pin, per transport (connected, still connecting, connected later, Duplex, Duplex with a close(code, callback) of its own), identical on node v26.3.0 and this branch. The peer keeps its side open (allowHalfOpen), so the stream stays open under the wrap:

• end(): 'finish', the peer sees the FIN, the wrap is readOnly, nothing is destroyed. A socket that is not connected yet gets its 'connect' first.
• destroySoon(): 'finish', 'close', the peer sees the FIN, the wrap and the stream are destroyed.
• destroy(): 'close', the wrap and the stream are destroyed. Over a socket that is already connected the peer sees the FIN of the closed transport. The stream's own close() is never called. With the typeof close form of the check that cell fails: close() receives the completion callback and the stream survives.

peerSawFin in these reports is what the peer's 'end' handler recorded, and the key is present only where a FIN is owed.

The last two tests close the stream under the wrap, again identical on node v26.3.0 and this branch:

• A peer that closes when the FIN arrives: end() gives 'finish', 'close', and the wrap and the stream are destroyed.
• A refused connection: end() and destroySoon() wait for 'connect', the stream reports ECONNREFUSED and closes, and the wrap closes with it ('close', no 'finish').

The wrap follows the 'close' of its stream one tick later, and only while that stream is still its handle. One tick later, because the stream machinery emits 'finish' one tick after the _final callback: a stream that fails in its own final calls back and closes in the same turn, and node reports 'finish' and then 'close' for it (measured, and the same here). Only while it is the handle, because after connect({ socket }) the native handle reports the close.

This PR guards 2 of the 6 places where node:net calls the wrapped stream as if it were a native handle. The other four are older than #42181, throw from the call itself (so the caller can catch them), and are unchanged here:

• _write calls _handle.$write(): write(), end(data), end('') and uncork() throw socket.@write is not a function.
• ref() and unref() call _handle.ref() / _handle.unref(): they throw over a generic Duplex (a wrapped net.Socket has both).
• resetAndDestroy() calls _handle.terminate().

The wrap exists in this form so that _handle._parentWrap works for http2-wrapper. #37664 removes all four sites, because the wrap then has a native handle. When the _handle = socket assignment in the constructor goes away, the two branches added here are dead code and can go with it.

Found on the way, handed off separately:

• end() before the TLS handle is attached emits 'finish' and sends no FIN: tls.connect({ socket: stillConnecting }).end(), and new TLSSocket(sock, { isServer: true }).end() in the same tick. Both are older than tls: end() and destroySoon() before the handshake completes now send the FIN #42181.
• endNT calls shutdown() with no guard, so any throw there is an uncaught exception.

Differences from node that remain:

• Node also forwards the 'error' of the stream: the constructor adds wrap.on('error', err => this._emitTLSError(err)), so the TLS socket emits '_tlsError' (and 'error' once control is released), and the stream's error never counts as unhandled. Bun's client-side wrap does not listen for it until connect() upgrades it, so a wrapped socket that fails with no 'error' listener of its own is still an uncaught exception. That is older than this PR. node:tls: make client-side new TLSSocket(socket) upgrade the socket it wraps #37664 closes it.
• The wrap does not read its transport, so after the peer's FIN it emits 'close' but no 'end'.
• Node shuts the TCP handle down below the wrapped net.Socket, so that socket has writableEnded === false and emits no 'finish'. Here the wrapped socket ends through its own end(), so it reports both. For a wrapped Duplex node calls end() too, and the reports are identical.

The order of the checks in _final: a write that happened before the handshake still parks on the handshake signal first, as #42181 left it. The stream branch applies only while _handle instanceof Duplex, which only the client-side constructor branch produces. After connect({ socket }) the handle is native and the old path runs.

On the fixture: an uncaught exception does not end a bun process while the top-level await of the entry module is pending (#22546). The process prints the error and keeps running. The fixture installs an uncaughtException handler that prints and exits 1, so the new tests fail in about 2 s with the TypeError in the assertion, and do not time out.

Review findings: two reviewers asked _final to settle when a wrapped socket fails before 'connect', and one asked it to forward the error of stream.end(). Node does neither (measured on v26.3.0: the end() callback of a wrap over a stream whose final fails gets no error, and a refused connection leaves _final unsettled). What node does have is the close path above, which is now in.

Suites run with a debug build of this branch, compared with a debug build of main:

• test/js/node/tls/node-tls-connect.test.ts: 85 pass, 18 skip, 0 fail (after the rebase onto f385d9a).
• tsc --noEmit -p src/js/tsconfig.json (the typecheck of the built-in modules that CI runs since Typecheck the built-in modules (src/js) in CI #43649): no error.
• test/js/node/test/parallel/test-tls-*.js (186 files): 185 pass. test-tls-client-allow-partial-trust-chain.js needs the node:test runner.
• test-https-*, test-http2-*, test-net-* (473 files): 461 pass. The 12 that fail (test-https-proxy-request*.mjs, test-https-request-proxy-post.mjs, test-https-timeout.js, two node:test files) fail the same way on main in this environment.
• test/js/node/tls/*.test.ts, test/js/node/net/*.test.ts: no new failure. node-tls-server.test.ts (2) and node-net.test.ts (11) have failures that need DNS or more than 5 s on a debug build, identical on main.

Self-reviewed: 3 changes requested, 3 made. closeSocketHandle tests instanceof Duplex. A cell covers a stream with its own close(). The destroy() cells from #35842 are in.

---

[human-review] gate passed · iteration 1 · 4 files touched

fails on main (without fix)

ASAN without fix: 7 failed, 18 skipped
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/node/tls/node-tls-connect.test.ts
bun test v1.4.3 (367d939d9)

test/js/node/tls/node-tls-connect.test.ts:
(pass) should have checkServerIdentity [2.66ms]
(pass) should thow ECONNRESET if FIN is received before handshake [298.99ms]
(pass) initializes authorizationError to null in the TLSSocket constructor [6.50ms]
(pass) setMaxSendFragment mirrors OpenSSL's [512, 16384] acceptance without throwing [126.61ms]
(pass) should be able to grab the JSStreamSocket constructor [15.87ms]
(skip) tls.connect > should work with alpnProtocols
(pass) tls.connect > Bun.serve() should work with tls and Bun.file() [74.10ms]
(pass) tls.connect > should have peer certificate when using self asign certificate [73.52ms]
(skip) tls.connect > should have peer certificate
(skip) tls.connect > getCipher, getProtocol, getEphemeralKeyInfo, getSharedSigalgs, getSession, exportKeyingMaterial and isSessionReused should work
(skip) tls.connect > should process options correctly when connect is called with only options
(skip) tls.connect > should process port an
... (truncated)

release without fix: 18 skipped
bun test v1.4.3-canary.1 (847fb6544)

test/js/node/tls/node-tls-connect.test.ts:
(pass) should have checkServerIdentity [0.09ms]
(pass) should thow ECONNRESET if FIN is received before handshake [7.13ms]
(pass) initializes authorizationError to null in the TLSSocket constructor [0.14ms]
(pass) setMaxSendFragment mirrors OpenSSL's [512, 16384] acceptance without throwing [4.36ms]
(pass) should be able to grab the JSStreamSocket constructor [0.36ms]
(skip) tls.connect > should work with alpnProtocols
(pass) tls.connect > Bun.serve() should work with tls and Bun.file() [5.95ms]
(pass) tls.connect > should have peer certificate when using self asign certificate [4.29ms]
(skip) tls.connect > should have peer certificate
(skip) tls.connect > getCipher, getProtocol, getEphemeralKeyInfo, getSharedSigalgs, getSession, exportKeyingMaterial and isSessionReused should work
(skip) tls.connect > should process options correctly when connect is called with only options
(skip) tls.connect > should process port and host correctly
(skip) tls.connect > should process port, host, and callback correctly
(skip) tls.connect > should handle the absence of a callback gracefully
(skip) tls.c
... (truncated)

passes on PR (with fix)

ASAN with fix: 18 skipped
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/node/tls/node-tls-connect.test.ts
bun test v1.4.3 (367d939d9)

test/js/node/tls/node-tls-connect.test.ts:
(pass) should have checkServerIdentity [3.01ms]
(pass) should thow ECONNRESET if FIN is received before handshake [297.76ms]
(pass) initializes authorizationError to null in the TLSSocket constructor [6.38ms]
(pass) setMaxSendFragment mirrors OpenSSL's [512, 16384] acceptance without throwing [92.93ms]
(pass) should be able to grab the JSStreamSocket constructor [17.23ms]
(skip) tls.connect > should work with alpnProtocols
(pass) tls.connect > Bun.serve() should work with tls and Bun.file() [72.63ms]
(pass) tls.connect > should have peer certificate when using self asign certificate [72.80ms]
(skip) tls.connect > should have peer certificate
(skip) tls.connect > getCipher, getProtocol, getEphemeralKeyInfo, getSharedSigalgs, getSession, exportKeyingMaterial and isSessionReused should work
(skip) tls.connect > should process options correctly when connect is called with only options
(skip) tls.connect > should process port and
... (truncated)

release with fix: 18 skipped
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped) in 976ms (unchanged)
ninja: Entering directory `/workspace/bun/build/release'
[1/212] gen generated_host_exports.rs
generated_host_exports.rs: 121 exports (host=5, lazy=10, generic=106, rust=0); 245 extern-C blocks audited
[2/212] gen ZigGeneratedClasses.{cpp,h,rs}
Found 2 classes from /workspace/bun/src/jsc/resolve_message.classes.ts
  - ResolveMessage (15 fields)
  - BuildMessage (10 fields)
Found 1 classes from /workspace/bun/src/runtime/api/Archive.classes.ts
  - Archive (4 fields, 1 class fields)
Found 2 classes from /workspace/bun/src/runtime/api/BunObject.classes.ts
  - ResourceUsage (8 fields)
  - Subprocess (20 fields)
Found 1 classes from /workspace/bun/src/runtime/api/cron.classes.ts
  - CronJob (5 fields)
Found 3 classes from /workspace/bun/src/runtime/api/filesystem_router.classes.ts
  - FileSystemRouter (5 fields)
  - FrameworkFileSystemRouter (2 fields)
  - MatchedRoute (8 fields)
Found 1 classes from /workspace/bun/src/runtime/api/Glob.classes.ts
  - Glob (5 fields)
Found 1 classes from /workspace/bun/src/runtime/api/h2.classes.ts
  - H2FrameParser (29 fields)
Found 
... (truncated)

diff hotspot

src/js/node/net.ts                                 |  7 +-
 src/js/node/tls.ts                                 | 19 ++++-
 test/js/node/tls/node-tls-connect.test.ts          | 77 +++++++++++++++++-
 .../tls/tls-shutdown-before-handshake-fixture.mjs  | 91 +++++++++++++++++++++-
 4 files changed, 185 insertions(+), 9 deletions(-)

gate history · 3 passed · 0 rejected · iteration 1

evidence per changed file

file                                                      reads  edits  tests
src/js/node/net.ts                                            6      2     40
src/js/node/tls.ts                                            4      3     38
test/js/node/tls/node-tls-connect.test.ts                     5      7     34
…t/js/node/tls/tls-shutdown-before-handshake-fixture.mjs      6     12     36

[robobun]

Status: closed in favor of #37664 (maintainer decision). That PR removes the cause. The wrap matrix from this PR is handed over there: #37664 (comment)

Main still has the bug until #37664 lands. Reproduction, with the script from the report (in the PR notes) on a debug build of main:

bun bd t1.cjs end          # TypeError: socket.shutdown is not a function, exit 1
bun bd t1.cjs destroySoon  # same

This branch (e5de3ab, based on f385d9a) stays available: none of the 12 reported cells throws on it, both modes of the script print the same lines as node v26.3.0, test/js/node/tls/node-tls-connect.test.ts passes (85 pass, 0 fail), and build 120141 passed 181 of 181 jobs.

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---

Walkthrough

The runtime now handles wrapped Duplex streams during TLS shutdown. Tests cover connected, connecting, refused, stalled, and custom Duplex transports, including lifecycle events and resource cleanup.

Changes

TLS shutdown handling

Layer / File(s)	Summary
Runtime handle shutdown src/js/node/net.ts, src/js/node/tls.ts	Duplex handles are destroyed directly. Pending network sockets wait for connection, while generic Duplex handles are ended during TLS finalization. Wrapped transport closure schedules TLS socket cleanup.
Shutdown fixture coverage test/js/node/tls/tls-shutdown-before-handshake-fixture.mjs	The fixture tests end, destroySoon, and destroy across wrapped transport types. It records socket and transport state and handles stalled peers and uncaught exceptions.
TLS shutdown assertions test/js/node/tls/node-tls-connect.test.ts	Tests verify shutdown events, FIN delivery, writable completion, TLS state, transport destruction, refused connections, and detached socket cleanup.

Suggested reviewers: cirospaciari

Priority: ⬇️ Low

Merge Risk: ⚪ Minimal · up to e5de3

Ending or destroying a client-side TLS socket that wraps a JavaScript stream now shuts down the underlying stream instead of calling methods it does not implement. As in Node.js, a finalization error still surfaces on the wrapped stream's own error event rather than failing the TLS socket's end(). No remaining merge-blocking risk was found.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and specifically summarizes the main change: shutting down wrapped streams when a client-side TLSSocket ends or is destroyed.
Description check	✅ Passed	The description explains the problem, implementation, behavior, scope, and verification results. It provides substantially more detail than the required template sections.

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Actionable comments posted: 2

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Inline comments:
In `@src/js/node/tls.ts`:
- Line 913: Update the wrapper around handle.end in the TLS stream finalization
path to forward the completion error to the outer callback instead of discarding
it, preserving successful completion behavior when no error occurs. Add a
regression test using a wrapped Duplex whose final callback receives an error
and assert that the error is propagated without reporting successful
finalization.
- Around line 906-908: Update TLSSocket.prototype._final to settle its callback
when a pending wrapped NetSocket emits an error or closes before connect, while
preserving the existing retry through _final after a successful connect. Ensure
the pending failure/close listeners are cleaned up and the final callback is
invoked exactly once.

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⚠️ Outside diff range comments (1)

src/js/node/tls.ts (1)

913-913: 🩺 Stability & Availability | 🟡 Minor | ⚡ Quick win

Pass wrapped-stream finalization errors to the TLS final callback. When TLSSocket._final handles a wrapped Duplex, handle.end passes the wrapped stream’s _final error to its callback. The current callback discards that error, so TLS finalization can report success instead of propagating the failure. Change it to handle.end(error => callback(error)).

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In `@src/js/node/tls.ts` at line 913, Update TLSSocket._final’s wrapped-Duplex
handle.end callback to forward the received finalization error to the TLS final
callback instead of discarding it; preserve successful completion when no error
is provided.

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Outside diff comments:
In `@src/js/node/tls.ts`:
- Line 913: Update TLSSocket._final’s wrapped-Duplex handle.end callback to
forward the received finalization error to the TLS final callback instead of
discarding it; preserve successful completion when no error is provided.

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[robobun]

On the "outside diff" comment in the latest CodeRabbit review (forward the error of handle.end() to the _final callback): this is the finding from the thread at #42330 (comment), which ended as invalid. Not changed, for the same reason.

Node completes this shutdown with status 0 whatever stream.end() reports: this.stream.end(() => { this.finishShutdown(handle, 0); }) (js_stream_socket.js#L155-L160). Measured on node v26.3.0 with a wrapped Duplex whose final fails: the end() callback of the TLS socket gets no error, 'finish' fires, then 'close'. Since 12f39c1 this branch prints the same three lines, because the wrap now closes with its stream. handle.end(error => callback(error)) would replace 'finish' with an error on the TLS socket, which node does not report there.

[robobun]

^{Updated 6:53 PM PT - Sep 23rd, 2026}

✅ @robobun, your commit e5de3ab69ad2789baacd92195ba98b8ea8a43e92 passed in Build #120141! 🎉

---

🧪   To try this PR locally:

bunx bun-pr 42330

That installs a local version of the PR into your bun-42330 executable, so you can run:

bun-42330 --bun

[claude]

Thanks — commit 12f39c1 addresses the refused-connection hang I flagged: the constructor-level socket.once("close", …) → destroy() forwarding (matching Node's _wrapHandle) now tears the wrap down when the transport dies without connecting, and the new "refused" fixture case pins it. I re-ran the review on the updated diff and didn't find further bugs; a human look is still worthwhile since closeSocketHandle in node:net sits on every socket's destroy path.

What was reviewed:

• _final's new Duplex branch: handle.end(() => callback()) discards the error arg — matches Node's JSStreamSocket.doShutdown, which always reports status 0.
• closeSocketHandle: native handles are not Duplex instances, so the new branch only fires for the client-wrap case; the http2-stream close(code, cb) collision the instanceof check was chosen to avoid is covered by the duplex-with-close cell.
• destroyWithTransportNT's self._handle === transport guard prevents a stale transport 'close' from destroying a wrap that connect() has since upgraded.

Extended reasoning...

Overview

This PR fixes an unreleased regression where new tls.TLSSocket(stream) (client-side, no connect()) followed by end()/destroySoon() threw an uncaught TypeError: socket.shutdown is not a function from endNT, because the wrapped Duplex stands in as _handle and has no native shutdown()/close(). Two production changes: src/js/node/net.ts closeSocketHandle now branches on handle instanceof Duplex and calls handle.destroy() instead of handle.close(cb); src/js/node/tls.ts _final now ends the wrapped stream via handle.end(cb) (waiting for 'connect' on a still-pending net.Socket), and the constructor forwards the transport's 'close' to self.destroy() one tick later. Tests add a 7-transport × 3-method matrix run against both Bun and real Node via the same fixture.

Since my earlier inline finding, commit 12f39c1 added the transport-'close' → destroy() forwarding and a "refused" test case, which resolves the concern that a wrapped socket whose connection is refused would leave _final pending forever. The wrap now destroys when the underlying socket emits 'close', and the _handle === transport guard keeps that from firing after connect() upgrades the handle.

Security risks

None identified. The affected path is the pre-handshake client-side wrap where no TLS session exists yet; the change governs stream teardown ordering, not certificate validation, hostname checking, or any crypto surface. No user-controlled data reaches a parser or allocator.

Level of scrutiny

Medium-high. The production diff is small (~15 lines across two files) and each branch is gated on handle instanceof Duplex, which only the client-side TLSSocket constructor produces — but closeSocketHandle runs on every net.Socket destroy, so the guard's precision matters. The fix is well-cited to nodejs/node source (js_stream_socket.js doShutdown/doClose, tls/wrap.js _wrapHandle), and the test matrix runs identically under real Node v26.3.0, which is the strongest available check for Node-compat correctness. Given it's a bot-authored change on a load-bearing shutdown path, a maintainer sign-off is still appropriate.

Other factors

No CODEOWNERS cover these paths. The two coderabbit inline threads were resolved by a non-author. Test conventions look right: port: 0, describe.each/.concurrent, awaiting events (once(socket, settled)) rather than sleeping, hermetic local net.createServer, fixture cross-run under both runtimes, and an uncaughtException handler in the fixture so a regression fails fast instead of timing out. Two pre-existing tests now .destroy() their detached wraps, which the new close-forwarding makes safe.

[alii]

@robobun Buildkite failed on this head (12f39c1, https://buildkite.com/bun/bun/builds/114322, Sep 11) and it has not run since. Please rebase onto main so CI runs again. #42350 edits the same fixture (tls-shutdown-before-handshake-fixture.mjs) and node-tls-connect.test.ts, so expect a conflict with it. Whichever lands second needs a rebase.

[robobun]

@alii Rebased onto main (f385d9a), new head 847fb65. The rebase had no conflict. CI runs again on this head.

Checked on the rebased tree, with a debug build:

• test/js/node/tls/node-tls-connect.test.ts: 85 pass, 0 fail. With src/ at current main the 7 new tests still fail with TypeError: socket.shutdown is not a function, so main still has the bug.
• tsc --noEmit -p src/js/tsconfig.json (new in CI since Typecheck the built-in modules (src/js) in CI #43649): no error.
• Vendored test-tls-*.js: 185 of 186 pass. test-tls-client-allow-partial-trust-chain.js needs the node:test runner and fails the same way on main.

On the old red build (114322): the only red test was test/js/bun/http/serve-pending-promise-abort-leak.test.ts on x64-asan, which also failed on the PRs merged at that time. This diff does not touch it.

On #42350: it is still open, so there is no conflict with main today. I did a trial merge of its branch into this one. In src/ the two do not overlap (#42350 changes only src/runtime/socket/UpgradedDuplex.rs, this PR only src/js/node/tls.ts and net.ts). The conflicts are in tls-shutdown-before-handshake-fixture.mjs and node-tls-connect.test.ts, where both PRs add fixture modes and tests next to each other. Both sides can be kept as they are. I will rebase this PR if #42350 lands first.

[claude]

Beyond the inline finding, I also checked two things on this push: the refused/never-connecting wrapped net.Socket case raised on the previous version is now settled by the transport 'close' -> destroyWithTransportNT path (and pinned by the new refused-port cells), and the instanceof Duplex branches in _final and closeSocketHandle can only match the client-side constructor's pre-connect() handle, since the server-side wrap and connect({ socket }) both assign a native handle, so the existing native shutdown()/close() paths are unchanged for those.

Extended reasoning...

The change touches src/js/node/tls.ts and src/js/node/net.ts to make a client-side new tls.TLSSocket(stream) wrap end/destroy its wrapped stream instead of calling native shutdown()/close() on a JS Duplex, plus a test matrix and fixture. No security-sensitive surface (no auth, crypto parameters, or TLS verification flags are altered). Verified findings remain to be posted inline and the new commits landed after a maintainer comment, so a human look is still warranted rather than approval.

[claude]

Code review completed

Nothing new to post: everything this review found is already covered by existing comments on this pull request or didn't merit a separate one.

[alii]

Closing this in favor of #37664. That PR removes the cause, the client wrap keeping the wrapped stream as its handle, instead of guarding two of the sites that call into it. It needs a rebase onto main first. The 21-cell matrix from this PR should be its acceptance test. Reopen this if #37664 cannot land in time.

[robobun]

Understood. #37664 removes the cause, and this PR only guarded two of the call sites.

The matrix is handed over: #37664 (comment) has the commands to move the fixture and the tests (their diff applies cleanly on current main), the 21 cells, what node does in each group of cells, and the 12-cell throw script from the report.

For the release timing: main still throws TypeError: socket.shutdown is not a function on new tls.TLSSocket(stream).end() until #37664 lands. It is a regression from #42181 that is in no release yet. This branch stays as it is (e5de3ab, based on f385d9a, build 120141 passed 181 of 181 jobs), so it can be reopened and rebased if #37664 cannot land in time.