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Close a body's stream when a consumer takes its payload without reading it - #42516
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…ng it ReadableStream::to_any_blob lifts the whole payload out of an unread native stream when that payload is already in memory or is a file. The body mixin methods arrayBuffer(), bytes(), blob(), json() and formData() use it, and so do clone(), Bun.serve, fetch() uploads, Bun.write and Bun.spawn stdin. It marked the stream disturbed and locked but left it in the readable state: node:stream's isReadable() stayed true, Bun.inspect() printed state: 'readable', and stream.finished() never settled. Node closes the stream. Since #42116 keeps a consumed body's stream locked, nothing else can run it to its end either. to_any_blob now closes the stream. A stream that a native consumer attaches to while the payload still arrives does not take this path and is not changed here. The stand-in stream that .body returns for a consumed body was readable and undisturbed. It is now closed and disturbed. The stand-in for a body that a consumer still reads stays as it was.
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Updated 3:35 PM PT - Sep 12th, 2026
❌ @robobun, your commit 76d981d has 3 failures in
🧪 To try this PR locally: bunx bun-pr 42516That installs a local version of the PR into your bun-42516 --bun |
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Status: ready to merge. The diff is green. The two red CI jobs are not caused by this PR. How I reproduced it, with a debug build of import { isReadable } from "node:stream";
import { finished } from "node:stream/promises";
const res = new Response("hello world");
const body = res.body;
await res.arrayBuffer();
console.log(isReadable(body), Bun.inspect(body)); // true, state: 'readable' (node v26.3.0: false, 'closed')
await finished(body); // never settles (node settles)
CI on 76d981d (build 114862): 179 jobs passed, 2 failed.
All other annotations passed on a retry or passed alone: Related work that this PR does not include: #42477 (a stream that a native sink is wired to), #33461 ( |
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WalkthroughThe change distinguishes consumed body streams from actively used streams. Native bindings close consumed streams, runtime code preserves readable locked streams during active consumption, and fetch body tests verify lifecycle states across extraction and adoption paths. ChangesReadable stream state bindings
Runtime body integration
Stream lifecycle validation
Suggested reviewers: Priority: ➖ Normal Merge Risk: ⚪ Minimal · up to The stream lifecycle changes and their active-consumer distinction have no remaining actionable merge risk. 🚥 Pre-merge checks | ✅ 4✅ Passed checks (4 passed)
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In `@test/js/web/fetch/body.test.ts`:
- Around line 1687-1690: Replace the nested source and method loops around the
body consumption tests with describe.each() parameter tables, preserving the
existing source-specific inclusion of formData for URLSearchParams and the
generated test coverage for text, json, arrayBuffer, bytes, and blob. Keep the
test behavior and assertions unchanged.
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src/jsc/bindings/webcore/streams/WebStreamsExports.cppsrc/jsc/bindings/webcore/streams/WebStreamsInternals.hsrc/runtime/webcore/Body.rssrc/runtime/webcore/ReadableStream.rstest/js/web/fetch/body.test.ts
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I reviewed this PR and didn't find any bugs. Because it changes WHATWG stream state-machine transitions across the C++/Rust FFI boundary and intentionally diverges from Node on one observable (clone() closes the old stream immediately rather than when a branch drains), a human look would still be worthwhile.
What was reviewed:
- FFI parity:
ReadableStream__used(global, bool)andReadableStream__closeConsumedAsBodymatch parameter-for-parameter on the Rustexternblock and the C++ definitions/header. - Exception discipline in
ReadableStream__closeConsumedAsBody: tracedreadableStreamClose— with!m_readerit returns right afterresolveStreamClosedPromise(vm, stream), which only enqueues a promise resolution and runs no script, soassertNoExceptionExceptTerminationunder a top scope is sound; the header's// userJS: notag is consistent. lockedobservable after the new close:m_consumedAsBodyfeedsnativeHandleDetached()→isReadableStreamLocked, so the closed stream still reportslocked: trueas the tests assert.- Dead-code check:
mark_consumed_as_bodystill has a caller atBody.rs:438, so keepingReadableStream__markConsumedAsBodyis correct.
Extended reasoning...
Overview
The PR closes a native ReadableStream when a body-mixin consumer lifts its entire payload without going through a reader. It adds one C++ export (ReadableStream__closeConsumedAsBody) that sets m_disturbed/m_consumedAsBody and calls the existing readableStreamCloseIfPossible helper, adds a bool consumed parameter to ReadableStream__used so the stand-in stream for an already-consumed body is closed+disturbed, and splits the Rust wrapper into used() (consumed) and in_use() (still reading). to_any_blob now calls the new close export instead of mark_consumed_as_body. About 130 lines of new tests in test/js/web/fetch/body.test.ts cover the variant matrix (all body sources × all mixin methods, .body-then-consume vs consume-then-.body, clone(), Blob.stream()/Bun.file(), Bun.serve, fetch upload, Bun.write, and a negative test that a still-in-flight body's stand-in stays readable).
Security risks
None identified. This is internal stream state bookkeeping — no parsing of untrusted input, no auth/crypto/permissions, no new allocations or ownership transfers. The only script-reachable effect is settling an internal closed promise, which is enqueued (not run synchronously) and was already reachable via the existing text() path.
Level of scrutiny
Medium-high. The native diff is small (~40 lines) and reuses the shared readableStreamCloseIfPossible helper every other consumer teardown uses, but it changes spec-governed WHATWG stream state and an FFI signature. I verified the FFI signatures match on both sides, traced readableStreamClose to confirm the no-reader path runs no user JS (justifying assertNoExceptionExceptTermination), confirmed m_consumedAsBody still drives locked via nativeHandleDetached(), and checked that mark_consumed_as_body retains a caller so nothing is newly dead. Tests follow harness conventions (port: 0, tempDir, awaited conditions, no sleeps).
Other factors
The PR description documents one deliberate divergence from Node: after clone() on an unread native stream, the old stream is closed immediately (Node keeps it readable until a branch drains). It also names three sibling paths intentionally excluded (ReadableStream__lockNative for still-streaming payloads, Readable.fromWeb on m_transferred, and the node-fetch/undici shim resume()/destroy() behavior) and the PRs that will address them. A maintainer familiar with the streams state machine should confirm the clone() divergence and the sequencing against #42477/#42281 are acceptable. No CODEOWNERS entry covers these paths.
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…42609) ### Problem - `Bun.serve()` sends a second `Response` around an already sent `ReadableStream` as a `200` with an empty body. The `error` handler does not run. - A native sink consumer (`Bun.serve()`, a `fetch()` upload, `Bun.write()`, `Bun.spawn()` stdin, S3, `HTMLRewriter`) pumps a JS-backed stream in `BunStreamSource.cpp`. At the end `rsisFinally` (`:853`) releases the reader and `directStreamOnClose` (`:662`) drops the lock: `locked === false`. A `type: "direct"` stream, so every async iterable body, is not disturbed either. `RequestContext.rs:3152` checks the lock alone. - Found by a comparison with node v26.3.0, not by a user report. ### Fix - `rsisBegin` and `readDirectStream` call the new `JSReadableStream::markConsumedAsBody()` once the pump holds the stream. The stream stays locked after the pump lets go. - Behaviour change: after such a consumer took a stream, `getReader()`, `tee()`, `pipeTo()` and `cancel()` fail with a `TypeError`. Body mixin methods (#42116) and natively wired sinks (#42477) already do this. Neither is released. - `pipeTo()`, async iteration and `Bun.readableStreamTo*()` do not reach these pumps and still unlock. - Verified: `web-stream-state.test.ts` (30 new tests fail on main), `body.test.ts` (12), `serve-reused-response.test.ts` (2). Self-reviewed: 3 concerns, 2 addressed, 1 out of scope (Notes). ### Background - A JSSink is a native sink (`HTTPResponseSink`, `FileSink`). `JSSink::assign_to_stream` pumps a stream into it. - `readStreamIntoSink` reads through a default reader. `readDirectStream` gives the sink to the `pull()` of a direct stream. - `m_consumedAsBody` (#42116) is a bit that `isReadableStreamLocked()` includes and nothing clears. The fetch spec never releases the reader of a body. <details><summary>Notes</summary> **The rule.** A consumer that takes a stream as a body keeps it locked: the body mixin methods (#42116), `to_any_blob` lifts (#42516), natively wired `ByteStream`/`FileReader` sinks (#42477), and now the two pumps. A reader at the stream level releases its lock as the Streams spec says. Checked on this branch: `pipeTo()`, `pipeThrough()`, `for await`, `getReader()` + `releaseLock()`, `Bun.readableStreamToText()`, `Bun.readableStreamToArrayBuffer()`, `stream.text()`, `stream.bytes()`, `stream.json()`, `stream.blob()` all end with `locked === false`. **Scope of the pumps.** `readStreamIntoSink` and `readDirectStream` have one caller, `assignToStream`, which only `JSSinkController__assignToStream` calls (Rust `JSSink::assign_to_stream`: `HTTPResponseSink` and its TLS and HTTP/3 siblings, `FetchRequestBodySink`, `NetworkSink`, `FileSink`, `RewriterPipe`). **State on main.** The lock state after the hand-off depends on how the pump ended. A clean end and a sink that closes early (client gone, aborted upload, child exited) go through `rsisFinish` and release the reader one microtask after the stream closes. A producer error goes through `rsisAbrupt`, which orphans the reader, so that stream stays locked. A direct stream is never disturbed. **Repro (the user-visible part).** ```js const stream = new ReadableStream({ start(c) { c.enqueue(new TextEncoder().encode("payload")); c.close(); } }); const responses = [new Response(stream), new Response(stream)]; await using server = Bun.serve({ port: 0, fetch: () => responses.shift(), error: e => new Response(e.code, { status: 500 }) }); for (let i = 0; i < 2; i++) { const r = await fetch(server.url); console.log(r.status, JSON.stringify(await r.text())); } // main: 200 "payload", 200 "" // branch: 200 "payload", 500 "ERR_STREAM_CANNOT_PIPE" (Stream already used, please create a new one) ``` For a direct stream `new Response(stream)` per request shows the same on main: `200 "hello"`, `200 ""`, `500`. On this branch the second `new Response(stream)` throws `Body object should not be disturbed or locked`. **Other observable changes.** `request.bodyUsed` after `fetch(request)` with an async iterable body is now `true` (was `false`, the stream was not disturbed). `Bun.readableStreamToText(stream)` on a stream a sink holds rejects with "ReadableStream has already been used" in place of "ReadableStream is locked" (same `ERR_INVALID_STATE`). **Bare streams.** `fetch(url, { body: stream })`, `Bun.write(path, stream)` and `Bun.spawn({ stdin: stream })` keep a bare stream locked too. Natively wired sources already do this for the same calls (`ReadableStream__lockNative` never unlocks, see "errors a Bun.file() stream whose file does not open" from #42477). **node v26.3.0.** `fetch(url, { method: "POST", body: jsStream, duplex: "half" })`: afterwards `locked === true` and `getReader()` throws. The same after an upload that an `AbortSignal` stopped. The other five consumers are Bun APIs with no Node counterpart. **The mark comes after the reader acquisition.** A stream that another reader already holds is not marked. `Bun.serve()`, `fetch()`, `Bun.write()` and `HTMLRewriter` reject such a stream before the pump. `Bun.spawn()` stdin checks only `is_disturbed` (`stdio.rs:388`, `:536`), so a locked stream reaches the pump there. **Out of scope (the concern not addressed).** `rsisFinally` calls `clearStreamControllerSlots` also when the pump never got the lock. `Bun.spawn({ stdin: stream })` with a stream the caller holds through `getReader()` reaches that: the caller's `reader.read()` then never settles. This is the same on main and on this branch. #41532 rejects a locked stdin stream before the pump. **Not covered here.** - A handler that drains or partly reads a stream with its own reader, releases it, and then returns it in a `Response` still gets a `200` with the empty or remaining body. #36110 covers that gate. - Handing the same Node `Readable` or generator object to a second consumer makes a new stream each time. **Changed tests.** Three tests in `bun-write.test.js` (from #42114) read the terminal state through `stream.getReader().closed`. One test in `streams.test.js` (from #33781) polled `ts.readable.locked` to wait for the sink teardown. Both observed the unlock as a means, not as the subject. They use `finished()` from `node:stream/promises` now. The `streams.test.js` test still proves the teardown ran: `desiredSize` reads `null` only after the controller slot is cleared, and reads `0` for a stream that is only closed. **Fail before.** With `src/` from main and `bun bd`: `web-stream-state.test.ts` 30 of 46 fail, `body.test.ts` 12 of 778 fail, `serve-reused-response.test.ts` 2 of 9 fail, and the three `bun-write.test.js` tests fail on the new `locked` assertion. With this branch all pass. On main only the `Bun.serve()` row of "the stdout of a running child" fails: the other four consumers wire a pipe-backed `FileReader` natively. **Built-in JS.** I searched `src/js` for code that touches a stream after a native sink took it. The only `stream.cancel()` on a web stream is `ReadableFromWeb._destroy`, which #42573 handles for the body mixin case. **Earlier reports of the same class.** #7001 (fixed in #7861) and #6860. **Suites run on the debug build.** `test/js/web/streams/{streams,streams-leak,readable-stream-blob-consumed,readable-stream-terminal-barrier-release,transform-stream-leak}`, `test/js/third_party/wpt-streams`, `test/js/web/fetch/{body,body-stream,body-stream-excess,body-clone,body-async-iterator,body-mixin-errors,blob-write,fetch,fetch.stream,fetch-backpressure,fetch-abort-stream-body,fetch-stream-cancel-leak,fetch-redirect,response}`, `test/js/web/request/request`, `test/js/bun/http/{serve,bun-server,serve-reused-response,serve-direct-readable-stream,serve-body-leak,serve-pending-promise-abort-leak,async-iterator-stream,serve-async-stream-client-abort,serve-error-handler-stream,serve-response-stream-sink-leak,serve-stream-body-error,serve-stream-reject-flush-leak}`, `test/js/bun/spawn/{spawn,spawn-stdin-readable-stream}`, `test/js/bun/io/bun-write`, `test/js/workerd/{html-rewriter,html-rewriter-leak}`, `test/js/bun/s3/{s3-stream-cancel-leak,s3-stream-error-gc,s3-upload-stream-gc,s3-write-to-file-sync-close,s3-connection-close}`, `test/js/node/stream/{node-stream,web-stream-state}`, `test/js/node/async_hooks/AsyncLocalStorage`, `test/regression/issue/07001`. The failures that remain also fail with `src/` from main in this container: IPv6, tests that need a non-root user, external hosts, and 5 s timeouts of the debug build. </details> <!-- robobun:evidence:begin --> --- **no test proof** · iteration 0 · platform-specific test(s) that do not run on this machine, deferring to CI, which covers all platforms: test/js/web/streams/streams.test.js, test/js/bun/io/bun-write.test.js <!-- robobun:evidence:end -->
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…esponse (#42573) ### Problem - With the built-in `node-fetch` and `undici` shims, `res.body` emits `'error'` after a body method: `Invalid state: ReadableStream is locked` from `resume()`, `pipe()`, `for await`, and `Cannot cancel a locked ReadableStream` from `destroy()` (for example `finally { body.destroy() }`). Bun 1.4.2 and Node emit `'end'`, `'close'`. Regression from #42116 (not released). No user reported it. - Cause: `ReadableFromWeb` (`src/js/internal/webstreams_adapters.ts`) calls `stream.getReader()` in the first `_read()` and `stream.cancel()` in `_destroy()`. Since #42116 a body method keeps the web stream locked, so both throw. ### Fix - `ReadableFromWeb` takes a `responseBody` option. Both shims set it, `Readable.fromWeb()` does not. If the wrapper has not opened the web stream and the stream is locked, the Response took the body: `_read()` pushes `null`, `_destroy()` skips `cancel()`. - The check reads `stream.locked`, not `bodyUsed`: after an aborted `text()`, `bodyUsed` is `false` and the stream is locked. - `node-fetch`: the body methods no longer read `this.body` first, so the five overrides are deleted. `clone()` drops the cached node stream, because the body moves to a new web stream. - Verified: `test/js/node/http/node-fetch.test.js`, `test/js/first_party/undici/undici.test.ts` (27 new tests, 25 fail with main's `src/`). Self-reviewed: 3 concerns raised, 3 addressed. ### Background - Both shims hand out the body as a node `Readable` (`ReadableFromWeb`) around the web `ReadableStream` of a Bun `Response`. `text()`, `json()`, ... are the native methods and read the web stream directly. - `ReadableFromWeb` opens the web stream lazily, so a body method can take it while the wrapper has no reader. - Real `node-fetch` and `undici` read that node stream in `text()`, so it is ended afterwards. <details><summary>Notes</summary> **Origin.** Found during the review of #42516. That PR lists this symptom as tracked separately. **Reproduction.** ```js import nodeFetch from "node-fetch"; await using server = Bun.serve({ port: 0, fetch: () => new Response("hello") }); const res = await nodeFetch(server.url); const body = res.body; await res.arrayBuffer(); body.on("error", e => console.log("error:", e.message)).on("end", () => console.log("end")); body.resume(); // 1.4.2: end // main: error: Invalid state: ReadableStream is locked ``` **Behaviour per case**, both shims, checked against a 1.4.2 binary. "clean" means `end`, `close` for `resume()`, `close` for `destroy()`, and no chunks for `for await`. | case | 1.4.2 | main | this PR | | --- | --- | --- | --- | | `body` taken, then `text()` / `json()` / `arrayBuffer()` / `blob()` / `formData()` / `buffer()` / `bytes()`, then `resume()`, `destroy()` or `for await` | clean | `error` | clean | | body method first, then `res.body` for the first time | clean (`bytes()` throws) | `error` | clean | | `text()` aborted by the signal (or `AbortSignal.timeout()`), then `resume()` / `destroy()` | clean | `error` | clean | | `formData()` rejects the content type, then `resume()` / `destroy()` | clean | `error` | clean | | `json()` rejects with a `SyntaxError`, then `resume()` / `destroy()` | clean | `error` | clean | | `text()` still pending, then `resume()` / `destroy()` | `error` (locked) | `error` | clean, and `text()` resolves with the full body | | `body` taken, then `res.clone()`, then read `res.body` | throws (locked by `tee()`) | throws | `res.body` is a new node stream and delivers the body. The old node stream ends. | | `res.body` streamed with `for await`, `on("data")`, `pipe()` | works | works | works | | `destroy()` on a body that nothing read | cancels the fetch | same | same | **Why `stream.locked`.** The first version of this change asked the Response for `bodyUsed`. That misses every body method that rejects after it took the stream: on main `bodyUsed` stays `false` there while the stream stays locked (node reports `true` and locked). The lock of the stream itself is what makes `getReader()` and `cancel()` throw, so the wrapper checks that. **Why the overrides are deleted.** #6983 (for #6200) made `text()`, `json()`, `arrayBuffer()`, `blob()`, `formData()` read `this.body` first, because a wrapper made after the consume crashed in the stream code of that time. Such a wrapper now ends without an error, and the test for each body method reads `res.body` for the first time after the method. Without the preload a plain `await res.json()` does not create a web stream and a node stream that nothing reads. **`clone()`.** `super.clone()` moves the body of the original to a new web stream (a `tee()` branch, or a fresh stream over the same bytes). The cached wrapper held the old stream, so `res.body` taken before `clone()` threw `ReadableStream is locked` on read after it, also on 1.4.2. With the lock check it would have ended without data instead. `clone()` now clears the cache. Real `node-fetch` also replaces `body` with a new `PassThrough` in `clone()`. **A body method that fails** (abort, network error, bad JSON) leaves the node stream ended without an error. The rejected promise of the body method carries the error. **Not in this PR.** On main `bodyUsed` is `false` after a body method that rejects when `.body` was read before it. That is native (`src/runtime/webcore/Body.rs`) and #35847 covers the `formData()` part. **Suites run** on the debug build: `node-fetch.test.js`, `undici.test.ts`, `node-fetch-cjs.test.js`, `node-fetch-primordials.test.ts`, `undici-primordials.test.ts`, `node-stream.test.js`, `node-http-agent-free-socket.test.ts`, regression `26225`, `014865`, `04947`, and the Node `test-stream-readable-from-web-termination.js`, `test-readable-from-web-enqueue-then-close.js`, `test-whatwg-webstreams-adapters-to-*.js` files. </details> <!-- robobun:evidence:begin --> --- **[human-review]** gate passed · iteration 2 · 5 files touched <details><summary>fails on main (without fix)</summary> ```console ASAN without fix: 25 FAILED $ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/first_party/undici/undici.test.ts test/js/node/http/node-fetch.test.js bun test v1.4.3 (6a92015) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [68.88ms] (pass) undici > request > should error when body has already been consumed [13.68ms] 97 | const url = new URL(method, server.url).href; 98 | 99 | for (const [action, expected] of bodyActions) { 100 | const { body } = await request(url); 101 | await body[method](); 102 | expect(await eventsUntilClose(body, () => body[action]())).toEqual([...expected]); ^ error: expect(received).toEqual(expected) [ - "end", + [TypeError: Invalid state: ReadableStream is locked], "close", ] - Expected - 1 + Received + 1 at <anonymous> (/workspace/bun/test/js/first_party/undici/undici.test.ts:102:72) (fail) undici > request > body stream when a body method took the r ... (truncated) release without fix: all passed bun test v1.4.3-canary.1 (7b5b9c1) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [2.61ms] (pass) undici > request > should error when body has already been consumed [0.37ms] (pass) undici > request > body stream when a body method took the response > ends without an error after arrayBuffer() consumed it [5.40ms] (pass) undici > request > body stream when a body method took the response > ends without an error after blob() consumed it [1.87ms] (pass) undici > request > body stream when a body method took the response > ends without an error after formData() consumed it [2.11ms] (pass) undici > request > body stream when a body method took the response > ends without an error after json() consumed it [2.05ms] (pass) undici > request > body stream when a body method took the response > ends without an error after text() consumed it [1.75ms] (pass) undici > request > body stream when a body method took the response > resume() leaves a body method that is still reading alone [2.04ms] (pass) undici > request > body stream when a body method took the response > destroy() leaves a body method that ... (truncated) ``` </details> <details><summary>passes on PR (with fix)</summary> ```console 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/first_party/undici/undici.test.ts test/js/node/http/node-fetch.test.js bun test v1.4.3 (6a92015) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [78.45ms] (pass) undici > request > should error when body has already been consumed [15.95ms] (pass) undici > request > body stream when a body method took the response > ends without an error after arrayBuffer() consumed it [258.02ms] (pass) undici > request > body stream when a body method took the response > ends without an error after blob() consumed it [57.58ms] (pass) undici > request > body stream when a body method took the response > ends without an error after formData() consumed it [50.54ms] (pass) undici > request > body stream when a body method took the response > ends without an error after json() consumed it [48.81ms] (pass) undici > request > body stream when a body method took the response > ends without an error after text() consumed it [48.04ms] (pass) undici > request > body stream when a bo ... (truncated) release with fix: all passed $ bun scripts/build.ts --profile=release [configured] bun-profile → bun (stripped) in 639ms (unchanged) ninja: Entering directory `/workspace/bun/build/release' [1/21] gen JS modules (bundle-modules) Preprocess modules (7038ms) Bundle modules (48ms) Postprocesss modules (24ms) Bundle Functions (489ms) Generate Code (42ms) [7.65s] Bundled "src/js" for production 2600 kb 197 internal modules 13 native modules 50 internal functions across 16 files [1/6] cargo bun_runtime → libbun_runtime.a �[1m�[92m Compiling�[0m bun_core v0.0.0 (/workspace/bun/src/bun_core) �[1m�[92m Compiling�[0m bun_errno v0.0.0 (/workspace/bun/src/errno) �[1m�[92m Compiling�[0m bun_ptr v0.0.0 (/workspace/bun/src/ptr) �[1m�[92m Compiling�[0m bun_boringssl_sys v0.0.0 (/workspace/bun/src/boringssl_sys) �[1m�[92m Compiling�[0m bun_safety v0.0.0 (/workspace/bun/src/safety) �[1m�[92m Compiling�[0m bun_base64 v0.0.0 (/workspace/bun/src/base64) �[1m�[92m Compiling�[0m bun_cares_sys v0.0.0 (/workspace/bun/src/cares_sys) �[1m�[92m Compiling�[0m bun_zlib_sys v0.0.0 (/workspace/bun/src/zlib_sys) �[1m�[92m Compiling�[0m bun_zstd v0.0.0 (/workspace/bun/src/zstd) �[1m�[92m Compili ... (truncated) ``` </details> <details><summary>diff hotspot</summary> ``` src/js/internal/webstreams_adapters.ts | 30 ++++-- src/js/thirdparty/node-fetch.ts | 36 +------ src/js/thirdparty/undici.js | 2 +- test/js/first_party/undici/undici.test.ts | 127 +++++++++++++++++++++++++ test/js/node/http/node-fetch.test.js | 150 ++++++++++++++++++++++++++++++ 5 files changed, 304 insertions(+), 41 deletions(-) ``` </details> **gate history** · 2 passed · 0 rejected · iteration 2 <details><summary>evidence per changed file</summary> ``` file reads edits tests src/js/internal/webstreams_adapters.ts 5 11 17 src/js/thirdparty/node-fetch.ts 3 3 17 src/js/thirdparty/undici.js 2 3 17 test/js/first_party/undici/undici.test.ts 1 1 12 test/js/node/http/node-fetch.test.js 2 3 17 ``` </details> <!-- robobun:evidence:end -->
usrbinkat
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to usrbinkat/bun
that referenced
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Sep 15, 2026
…ven-sh#42609) ### Problem - `Bun.serve()` sends a second `Response` around an already sent `ReadableStream` as a `200` with an empty body. The `error` handler does not run. - A native sink consumer (`Bun.serve()`, a `fetch()` upload, `Bun.write()`, `Bun.spawn()` stdin, S3, `HTMLRewriter`) pumps a JS-backed stream in `BunStreamSource.cpp`. At the end `rsisFinally` (`:853`) releases the reader and `directStreamOnClose` (`:662`) drops the lock: `locked === false`. A `type: "direct"` stream, so every async iterable body, is not disturbed either. `RequestContext.rs:3152` checks the lock alone. - Found by a comparison with node v26.3.0, not by a user report. ### Fix - `rsisBegin` and `readDirectStream` call the new `JSReadableStream::markConsumedAsBody()` once the pump holds the stream. The stream stays locked after the pump lets go. - Behaviour change: after such a consumer took a stream, `getReader()`, `tee()`, `pipeTo()` and `cancel()` fail with a `TypeError`. Body mixin methods (oven-sh#42116) and natively wired sinks (oven-sh#42477) already do this. Neither is released. - `pipeTo()`, async iteration and `Bun.readableStreamTo*()` do not reach these pumps and still unlock. - Verified: `web-stream-state.test.ts` (30 new tests fail on main), `body.test.ts` (12), `serve-reused-response.test.ts` (2). Self-reviewed: 3 concerns, 2 addressed, 1 out of scope (Notes). ### Background - A JSSink is a native sink (`HTTPResponseSink`, `FileSink`). `JSSink::assign_to_stream` pumps a stream into it. - `readStreamIntoSink` reads through a default reader. `readDirectStream` gives the sink to the `pull()` of a direct stream. - `m_consumedAsBody` (oven-sh#42116) is a bit that `isReadableStreamLocked()` includes and nothing clears. The fetch spec never releases the reader of a body. <details><summary>Notes</summary> **The rule.** A consumer that takes a stream as a body keeps it locked: the body mixin methods (oven-sh#42116), `to_any_blob` lifts (oven-sh#42516), natively wired `ByteStream`/`FileReader` sinks (oven-sh#42477), and now the two pumps. A reader at the stream level releases its lock as the Streams spec says. Checked on this branch: `pipeTo()`, `pipeThrough()`, `for await`, `getReader()` + `releaseLock()`, `Bun.readableStreamToText()`, `Bun.readableStreamToArrayBuffer()`, `stream.text()`, `stream.bytes()`, `stream.json()`, `stream.blob()` all end with `locked === false`. **Scope of the pumps.** `readStreamIntoSink` and `readDirectStream` have one caller, `assignToStream`, which only `JSSinkController__assignToStream` calls (Rust `JSSink::assign_to_stream`: `HTTPResponseSink` and its TLS and HTTP/3 siblings, `FetchRequestBodySink`, `NetworkSink`, `FileSink`, `RewriterPipe`). **State on main.** The lock state after the hand-off depends on how the pump ended. A clean end and a sink that closes early (client gone, aborted upload, child exited) go through `rsisFinish` and release the reader one microtask after the stream closes. A producer error goes through `rsisAbrupt`, which orphans the reader, so that stream stays locked. A direct stream is never disturbed. **Repro (the user-visible part).** ```js const stream = new ReadableStream({ start(c) { c.enqueue(new TextEncoder().encode("payload")); c.close(); } }); const responses = [new Response(stream), new Response(stream)]; await using server = Bun.serve({ port: 0, fetch: () => responses.shift(), error: e => new Response(e.code, { status: 500 }) }); for (let i = 0; i < 2; i++) { const r = await fetch(server.url); console.log(r.status, JSON.stringify(await r.text())); } // main: 200 "payload", 200 "" // branch: 200 "payload", 500 "ERR_STREAM_CANNOT_PIPE" (Stream already used, please create a new one) ``` For a direct stream `new Response(stream)` per request shows the same on main: `200 "hello"`, `200 ""`, `500`. On this branch the second `new Response(stream)` throws `Body object should not be disturbed or locked`. **Other observable changes.** `request.bodyUsed` after `fetch(request)` with an async iterable body is now `true` (was `false`, the stream was not disturbed). `Bun.readableStreamToText(stream)` on a stream a sink holds rejects with "ReadableStream has already been used" in place of "ReadableStream is locked" (same `ERR_INVALID_STATE`). **Bare streams.** `fetch(url, { body: stream })`, `Bun.write(path, stream)` and `Bun.spawn({ stdin: stream })` keep a bare stream locked too. Natively wired sources already do this for the same calls (`ReadableStream__lockNative` never unlocks, see "errors a Bun.file() stream whose file does not open" from oven-sh#42477). **node v26.3.0.** `fetch(url, { method: "POST", body: jsStream, duplex: "half" })`: afterwards `locked === true` and `getReader()` throws. The same after an upload that an `AbortSignal` stopped. The other five consumers are Bun APIs with no Node counterpart. **The mark comes after the reader acquisition.** A stream that another reader already holds is not marked. `Bun.serve()`, `fetch()`, `Bun.write()` and `HTMLRewriter` reject such a stream before the pump. `Bun.spawn()` stdin checks only `is_disturbed` (`stdio.rs:388`, `:536`), so a locked stream reaches the pump there. **Out of scope (the concern not addressed).** `rsisFinally` calls `clearStreamControllerSlots` also when the pump never got the lock. `Bun.spawn({ stdin: stream })` with a stream the caller holds through `getReader()` reaches that: the caller's `reader.read()` then never settles. This is the same on main and on this branch. oven-sh#41532 rejects a locked stdin stream before the pump. **Not covered here.** - A handler that drains or partly reads a stream with its own reader, releases it, and then returns it in a `Response` still gets a `200` with the empty or remaining body. oven-sh#36110 covers that gate. - Handing the same Node `Readable` or generator object to a second consumer makes a new stream each time. **Changed tests.** Three tests in `bun-write.test.js` (from oven-sh#42114) read the terminal state through `stream.getReader().closed`. One test in `streams.test.js` (from oven-sh#33781) polled `ts.readable.locked` to wait for the sink teardown. Both observed the unlock as a means, not as the subject. They use `finished()` from `node:stream/promises` now. The `streams.test.js` test still proves the teardown ran: `desiredSize` reads `null` only after the controller slot is cleared, and reads `0` for a stream that is only closed. **Fail before.** With `src/` from main and `bun bd`: `web-stream-state.test.ts` 30 of 46 fail, `body.test.ts` 12 of 778 fail, `serve-reused-response.test.ts` 2 of 9 fail, and the three `bun-write.test.js` tests fail on the new `locked` assertion. With this branch all pass. On main only the `Bun.serve()` row of "the stdout of a running child" fails: the other four consumers wire a pipe-backed `FileReader` natively. **Built-in JS.** I searched `src/js` for code that touches a stream after a native sink took it. The only `stream.cancel()` on a web stream is `ReadableFromWeb._destroy`, which oven-sh#42573 handles for the body mixin case. **Earlier reports of the same class.** oven-sh#7001 (fixed in oven-sh#7861) and oven-sh#6860. **Suites run on the debug build.** `test/js/web/streams/{streams,streams-leak,readable-stream-blob-consumed,readable-stream-terminal-barrier-release,transform-stream-leak}`, `test/js/third_party/wpt-streams`, `test/js/web/fetch/{body,body-stream,body-stream-excess,body-clone,body-async-iterator,body-mixin-errors,blob-write,fetch,fetch.stream,fetch-backpressure,fetch-abort-stream-body,fetch-stream-cancel-leak,fetch-redirect,response}`, `test/js/web/request/request`, `test/js/bun/http/{serve,bun-server,serve-reused-response,serve-direct-readable-stream,serve-body-leak,serve-pending-promise-abort-leak,async-iterator-stream,serve-async-stream-client-abort,serve-error-handler-stream,serve-response-stream-sink-leak,serve-stream-body-error,serve-stream-reject-flush-leak}`, `test/js/bun/spawn/{spawn,spawn-stdin-readable-stream}`, `test/js/bun/io/bun-write`, `test/js/workerd/{html-rewriter,html-rewriter-leak}`, `test/js/bun/s3/{s3-stream-cancel-leak,s3-stream-error-gc,s3-upload-stream-gc,s3-write-to-file-sync-close,s3-connection-close}`, `test/js/node/stream/{node-stream,web-stream-state}`, `test/js/node/async_hooks/AsyncLocalStorage`, `test/regression/issue/07001`. The failures that remain also fail with `src/` from main in this container: IPv6, tests that need a non-root user, external hosts, and 5 s timeouts of the debug build. </details> <!-- robobun:evidence:begin --> --- **no test proof** · iteration 0 · platform-specific test(s) that do not run on this machine, deferring to CI, which covers all platforms: test/js/web/streams/streams.test.js, test/js/bun/io/bun-write.test.js <!-- robobun:evidence:end -->
usrbinkat
pushed a commit
to usrbinkat/bun
that referenced
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Sep 15, 2026
…esponse (oven-sh#42573) ### Problem - With the built-in `node-fetch` and `undici` shims, `res.body` emits `'error'` after a body method: `Invalid state: ReadableStream is locked` from `resume()`, `pipe()`, `for await`, and `Cannot cancel a locked ReadableStream` from `destroy()` (for example `finally { body.destroy() }`). Bun 1.4.2 and Node emit `'end'`, `'close'`. Regression from oven-sh#42116 (not released). No user reported it. - Cause: `ReadableFromWeb` (`src/js/internal/webstreams_adapters.ts`) calls `stream.getReader()` in the first `_read()` and `stream.cancel()` in `_destroy()`. Since oven-sh#42116 a body method keeps the web stream locked, so both throw. ### Fix - `ReadableFromWeb` takes a `responseBody` option. Both shims set it, `Readable.fromWeb()` does not. If the wrapper has not opened the web stream and the stream is locked, the Response took the body: `_read()` pushes `null`, `_destroy()` skips `cancel()`. - The check reads `stream.locked`, not `bodyUsed`: after an aborted `text()`, `bodyUsed` is `false` and the stream is locked. - `node-fetch`: the body methods no longer read `this.body` first, so the five overrides are deleted. `clone()` drops the cached node stream, because the body moves to a new web stream. - Verified: `test/js/node/http/node-fetch.test.js`, `test/js/first_party/undici/undici.test.ts` (27 new tests, 25 fail with main's `src/`). Self-reviewed: 3 concerns raised, 3 addressed. ### Background - Both shims hand out the body as a node `Readable` (`ReadableFromWeb`) around the web `ReadableStream` of a Bun `Response`. `text()`, `json()`, ... are the native methods and read the web stream directly. - `ReadableFromWeb` opens the web stream lazily, so a body method can take it while the wrapper has no reader. - Real `node-fetch` and `undici` read that node stream in `text()`, so it is ended afterwards. <details><summary>Notes</summary> **Origin.** Found during the review of oven-sh#42516. That PR lists this symptom as tracked separately. **Reproduction.** ```js import nodeFetch from "node-fetch"; await using server = Bun.serve({ port: 0, fetch: () => new Response("hello") }); const res = await nodeFetch(server.url); const body = res.body; await res.arrayBuffer(); body.on("error", e => console.log("error:", e.message)).on("end", () => console.log("end")); body.resume(); // 1.4.2: end // main: error: Invalid state: ReadableStream is locked ``` **Behaviour per case**, both shims, checked against a 1.4.2 binary. "clean" means `end`, `close` for `resume()`, `close` for `destroy()`, and no chunks for `for await`. | case | 1.4.2 | main | this PR | | --- | --- | --- | --- | | `body` taken, then `text()` / `json()` / `arrayBuffer()` / `blob()` / `formData()` / `buffer()` / `bytes()`, then `resume()`, `destroy()` or `for await` | clean | `error` | clean | | body method first, then `res.body` for the first time | clean (`bytes()` throws) | `error` | clean | | `text()` aborted by the signal (or `AbortSignal.timeout()`), then `resume()` / `destroy()` | clean | `error` | clean | | `formData()` rejects the content type, then `resume()` / `destroy()` | clean | `error` | clean | | `json()` rejects with a `SyntaxError`, then `resume()` / `destroy()` | clean | `error` | clean | | `text()` still pending, then `resume()` / `destroy()` | `error` (locked) | `error` | clean, and `text()` resolves with the full body | | `body` taken, then `res.clone()`, then read `res.body` | throws (locked by `tee()`) | throws | `res.body` is a new node stream and delivers the body. The old node stream ends. | | `res.body` streamed with `for await`, `on("data")`, `pipe()` | works | works | works | | `destroy()` on a body that nothing read | cancels the fetch | same | same | **Why `stream.locked`.** The first version of this change asked the Response for `bodyUsed`. That misses every body method that rejects after it took the stream: on main `bodyUsed` stays `false` there while the stream stays locked (node reports `true` and locked). The lock of the stream itself is what makes `getReader()` and `cancel()` throw, so the wrapper checks that. **Why the overrides are deleted.** oven-sh#6983 (for oven-sh#6200) made `text()`, `json()`, `arrayBuffer()`, `blob()`, `formData()` read `this.body` first, because a wrapper made after the consume crashed in the stream code of that time. Such a wrapper now ends without an error, and the test for each body method reads `res.body` for the first time after the method. Without the preload a plain `await res.json()` does not create a web stream and a node stream that nothing reads. **`clone()`.** `super.clone()` moves the body of the original to a new web stream (a `tee()` branch, or a fresh stream over the same bytes). The cached wrapper held the old stream, so `res.body` taken before `clone()` threw `ReadableStream is locked` on read after it, also on 1.4.2. With the lock check it would have ended without data instead. `clone()` now clears the cache. Real `node-fetch` also replaces `body` with a new `PassThrough` in `clone()`. **A body method that fails** (abort, network error, bad JSON) leaves the node stream ended without an error. The rejected promise of the body method carries the error. **Not in this PR.** On main `bodyUsed` is `false` after a body method that rejects when `.body` was read before it. That is native (`src/runtime/webcore/Body.rs`) and oven-sh#35847 covers the `formData()` part. **Suites run** on the debug build: `node-fetch.test.js`, `undici.test.ts`, `node-fetch-cjs.test.js`, `node-fetch-primordials.test.ts`, `undici-primordials.test.ts`, `node-stream.test.js`, `node-http-agent-free-socket.test.ts`, regression `26225`, `014865`, `04947`, and the Node `test-stream-readable-from-web-termination.js`, `test-readable-from-web-enqueue-then-close.js`, `test-whatwg-webstreams-adapters-to-*.js` files. </details> <!-- robobun:evidence:begin --> --- **[human-review]** gate passed · iteration 2 · 5 files touched <details><summary>fails on main (without fix)</summary> ```console ASAN without fix: 25 FAILED $ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/first_party/undici/undici.test.ts test/js/node/http/node-fetch.test.js bun test v1.4.3 (6a92015) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [68.88ms] (pass) undici > request > should error when body has already been consumed [13.68ms] 97 | const url = new URL(method, server.url).href; 98 | 99 | for (const [action, expected] of bodyActions) { 100 | const { body } = await request(url); 101 | await body[method](); 102 | expect(await eventsUntilClose(body, () => body[action]())).toEqual([...expected]); ^ error: expect(received).toEqual(expected) [ - "end", + [TypeError: Invalid state: ReadableStream is locked], "close", ] - Expected - 1 + Received + 1 at <anonymous> (/workspace/bun/test/js/first_party/undici/undici.test.ts:102:72) (fail) undici > request > body stream when a body method took the r ... (truncated) release without fix: all passed bun test v1.4.3-canary.1 (7b5b9c1) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [2.61ms] (pass) undici > request > should error when body has already been consumed [0.37ms] (pass) undici > request > body stream when a body method took the response > ends without an error after arrayBuffer() consumed it [5.40ms] (pass) undici > request > body stream when a body method took the response > ends without an error after blob() consumed it [1.87ms] (pass) undici > request > body stream when a body method took the response > ends without an error after formData() consumed it [2.11ms] (pass) undici > request > body stream when a body method took the response > ends without an error after json() consumed it [2.05ms] (pass) undici > request > body stream when a body method took the response > ends without an error after text() consumed it [1.75ms] (pass) undici > request > body stream when a body method took the response > resume() leaves a body method that is still reading alone [2.04ms] (pass) undici > request > body stream when a body method took the response > destroy() leaves a body method that ... (truncated) ``` </details> <details><summary>passes on PR (with fix)</summary> ```console 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/first_party/undici/undici.test.ts test/js/node/http/node-fetch.test.js bun test v1.4.3 (6a92015) test/js/first_party/undici/undici.test.ts: (pass) undici > request > should make a GET request when passed a URL string [78.45ms] (pass) undici > request > should error when body has already been consumed [15.95ms] (pass) undici > request > body stream when a body method took the response > ends without an error after arrayBuffer() consumed it [258.02ms] (pass) undici > request > body stream when a body method took the response > ends without an error after blob() consumed it [57.58ms] (pass) undici > request > body stream when a body method took the response > ends without an error after formData() consumed it [50.54ms] (pass) undici > request > body stream when a body method took the response > ends without an error after json() consumed it [48.81ms] (pass) undici > request > body stream when a body method took the response > ends without an error after text() consumed it [48.04ms] (pass) undici > request > body stream when a bo ... (truncated) release with fix: all passed $ bun scripts/build.ts --profile=release [configured] bun-profile → bun (stripped) in 639ms (unchanged) ninja: Entering directory `/workspace/bun/build/release' [1/21] gen JS modules (bundle-modules) Preprocess modules (7038ms) Bundle modules (48ms) Postprocesss modules (24ms) Bundle Functions (489ms) Generate Code (42ms) [7.65s] Bundled "src/js" for production 2600 kb 197 internal modules 13 native modules 50 internal functions across 16 files [1/6] cargo bun_runtime → libbun_runtime.a �[1m�[92m Compiling�[0m bun_core v0.0.0 (/workspace/bun/src/bun_core) �[1m�[92m Compiling�[0m bun_errno v0.0.0 (/workspace/bun/src/errno) �[1m�[92m Compiling�[0m bun_ptr v0.0.0 (/workspace/bun/src/ptr) �[1m�[92m Compiling�[0m bun_boringssl_sys v0.0.0 (/workspace/bun/src/boringssl_sys) �[1m�[92m Compiling�[0m bun_safety v0.0.0 (/workspace/bun/src/safety) �[1m�[92m Compiling�[0m bun_base64 v0.0.0 (/workspace/bun/src/base64) �[1m�[92m Compiling�[0m bun_cares_sys v0.0.0 (/workspace/bun/src/cares_sys) �[1m�[92m Compiling�[0m bun_zlib_sys v0.0.0 (/workspace/bun/src/zlib_sys) �[1m�[92m Compiling�[0m bun_zstd v0.0.0 (/workspace/bun/src/zstd) �[1m�[92m Compili ... (truncated) ``` </details> <details><summary>diff hotspot</summary> ``` src/js/internal/webstreams_adapters.ts | 30 ++++-- src/js/thirdparty/node-fetch.ts | 36 +------ src/js/thirdparty/undici.js | 2 +- test/js/first_party/undici/undici.test.ts | 127 +++++++++++++++++++++++++ test/js/node/http/node-fetch.test.js | 150 ++++++++++++++++++++++++++++++ 5 files changed, 304 insertions(+), 41 deletions(-) ``` </details> **gate history** · 2 passed · 0 rejected · iteration 2 <details><summary>evidence per changed file</summary> ``` file reads edits tests src/js/internal/webstreams_adapters.ts 5 11 17 src/js/thirdparty/node-fetch.ts 3 3 17 src/js/thirdparty/undici.js 2 3 17 test/js/first_party/undici/undici.test.ts 1 1 12 test/js/node/http/node-fetch.test.js 2 3 17 ``` </details> <!-- robobun:evidence:end -->
This was referenced Oct 10, 2026
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Problem
const body = res.body; await res.arrayBuffer()(orbytes(),blob(),json(),formData()) leavesbodyreadablewhen a string,Blob, typed array or file backs it.isReadable(body)returnstrue,Bun.inspect(body)printsstate: 'readable', andawait finished(body)never settles. Node v26.3.0 andtext()close the stream.ReadableStream::to_any_blob(src/runtime/webcore/ReadableStream.rs:195). It takes the payload out of the native source and marks the stream disturbed and locked, but never changesm_state. Since Keep body stream bookkeeping independent of the body's source #42116 (not released) the stream stays locked, so nothing can drain it either..bodyread after the consume returns a stand-in stream that isreadableand not disturbed.Fix
to_any_blobcalls the newReadableStream__closeConsumedAsBody: themarkConsumedAsBodyflags, then a close.to_any_blobfirst rejects a disturbed or locked stream. No reader or controller exists, so the close only sets the state and settles the closed promise.ReadableStream__usedmakes the stand-in for a consumed body closed and disturbed. The stand-in for a body still being read is unchanged.test/js/web/fetch/body.test.ts(99 new cases, 50 fail on main), plus the suites in Notes. Self-reviewed: 3 changes asked, 3 made.Background
ReadableStream. It gets a controller only when something reads it.Blob. The body methods,clone(),Bun.serve,fetch()uploads,Bun.writeandBun.spawnstdin do so when the payload is in memory or is a file.isReadable(),isErrored()andisDisturbed()read the stream's own state.finished()waits on a closed promise that each terminal transition settles.Notes
Origin. A differential run against node v26.3.0 after #42416 found this. No user reported it. On 1.4.2 the stream was also left
readable, but it was unlocked, sobody.getReader().read()returneddoneand closed it. #42116 keeps the stream locked (as undici and Chromium do), which removed that way out. This PR should land before the next release.Repro.
.bodythenarrayBuffer()/bytes()/blob()/json()/formData()finished()pending.bodythentext()new Response(blob.stream()).bytes(),Bun.file().stream(),new Response(Bun.file()).bodyfetch()response,.bodytaken, whole body arrived, thenarrayBuffer()Bun.servesends it,fetch()uploads it,Bun.writewrites it,Bun.spawnstdin (payload in memory or a file)await res.text(); res.body(stand-in).bodyafterclone()clone()The error messages of
getReader(),cancel(),tee(),pipeTo(),text(),Bun.readableStreamToText()andnew Response(body)on the consumed stream are the same as before.finished()registered before the consume settles too.Not in this PR.
ReadableStream__lockNative: afetch()upload,Bun.write,Bun.spawnstdin orBun.serveresponse of a body that still streams). It does not go throughto_any_blob. streams: end a ReadableStream when the native sink it is locked to is done #42477 fixes it. This PR should land first. The conflict inWebStreamsExports.cppis keep-both, and both usereadableStreamCloseIfPossiblefor the close.Readable.fromWeb()on a native stream (m_transferred): the web stream staysreadableafter the node stream ends. It is the same on 1.4.2. The fix touches the code that node:stream: take the native handle in Readable.fromWeb only from a stream no consumer has started #42281 changes, so it follows that PR.node-fetchandundicishims wrapres.bodyin a nodeReadable. Since Keep body stream bookkeeping independent of the body's source #42116,res.body.resume()ordestroy()after a body method emits'error'(the stream is locked). 1.4.2 emits'end'/'close'. This PR does not change that. It is tracked separately..bodyread whiletext()is still pending returns a stand-in that staysreadableand locked. Nothing tells it how the read ends, so it must not report closed. A new test pins this.getReader().releaseLock()marks a native stream disturbed: Stop treating a locked body stream as a consumed one #33461.WritableStreamstate: stream: expose WritableStream state to node:stream #42457.The stand-in for a consumed body is also what
.bodyreturns once a native consumer took a body that still streams (Bun.write(path, res)sets the body to used at once). It reads closed from then on. Before,finished()on it never settled.Self-review. It asked for three changes. The stand-in for a body still being read keeps its old state (
ReadableStream::in_use). The close goes throughreadableStreamCloseIfPossible, not a hand-written state write. The commit message and this body name the excluded paths and say that the native consumers take this path only when the payload is in memory or is a file.Suites run with the debug build and
BUN_JSC_validateExceptionChecks=1:test/js/web/fetch/body.test.ts(734 pass),body-stream.test.ts(9086 pass),body-clone.test.ts,body-mixin-errors.test.ts,blob.test.ts,fetch.stream.test.ts,test/js/web/streams/streams.test.js(549 pass),readable-stream-blob-consumed.test.ts,test/js/node/stream/web-stream-state.test.ts,test/js/third_party/wpt-streams/wpt-streams.test.ts(1175 pass),test/js/bun/spawn/spawn-stdin-readable-stream.test.ts,test/js/bun/io/bun-write.test.js,test/js/bun/util/inspect.test.js.[human-review] gate passed · iteration 1 · 5 files touched
fails on main (without fix)
passes on PR (with fix)
diff hotspot
gate history · 2 passed · 0 rejected · iteration 1
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