Resolve setImmediate, clearImmediate and queueMicrotask in built-in modules to private names by robobun · Pull Request #44917 · oven-sh/bun

robobun · 2026-10-10T12:07:11Z

Problem

Built-in modules call setImmediate, clearImmediate and queueMicrotask through the global object. When a program replaces them, as fake timers do, the runtime's own work is lost. A PerformanceObserver, events.addAbortListener() and fs.watch() never deliver, and a node:http2 session never closes.
With the globals deleted: ReferenceError: setImmediate is not defined at internal:shared. Cause: 40 bare references in 11 src/js modules (src/js/internal/shared.ts:394).

Fix

The three names join globalsToPrefix in src/codegen/replacements.ts: the globals that the builtin bundler rewrites to private names.
ZigGlobalObject.cpp installs each private name lazily. The public global is the same function object.
The builtins format version goes from 1 to 2, or bun 1.4.2 segfaults in bun build --compile --bytecode for a newer target. A source lint holds the rule.
Verified: test/js/bun/globals.test.js, 7 new cases fail without the fix. Self-reviewed: 5 concerns raised, 5 addressed.

Background

A private name (@setImmediate) is a global object property that user code cannot reach or replace.
bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987 covers the setTimeout deadlines of built-in modules. jest.useFakeTimers() holds those natively, so it needs a native part. Notes say how the two fit.
Rejected: a binding per file (fix(net): schedule close events independently of user timers #44366), an import per call site (bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987). Both miss new call sites.

Downsides

Fake timers no longer see the runtime's own immediates and microtasks: mock.timers.tick() does not run them. Node behaves the same.
Cost: 3 CustomGetterSetter cells per global object until first use, 2,184 bytes of binary. Per call: same bytecode (Notes).
--compile --bytecode embeds no builtin bytecode when only the host or only the target has this change.

Notes

How this fits with #37987

Both PRs are about one family: a built-in module schedules its own work through a global that user code can replace.
bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987 has the four timeout names (setTimeout, setInterval, clearTimeout, clearInterval). jest.useFakeTimers() in bun:test is native. It captures every timeout in the timer heap, whoever made it. So a private JS name does not help there. That PR adds native timers that the fake clock skips, and each call site imports them from internal/timers. A lint bans the globals.
This PR has setImmediate, clearImmediate and queueMicrotask. jest.useFakeTimers() does not hold immediates or microtasks. Only a replacement of the globals in JS reaches them: sinon or vitest fake timers, node:test mock.timers, happy-dom. A private name is the whole fix, with no change at a call site.
The four timeout names are not here on purpose. Their private slots must hold other functions than the public globals (the real clock), and that is the native part of bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987. src/js/internal/trace_events.ts:471 also wraps exactly those four public globals.
After this PR, bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987 can use the same rewrite for its JS side: four more rows in globalsToPrefix, with private slots that hold its real-clock functions. That removes its imports at each call site and its lint. The native part stays. I will rebase bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987 that way.
The PRs share two files, NodeTimers.cpp and NodeTimers.h. Each PR adds functions there.

Other open PRs

fix(net): schedule close events independently of user timers #44366 binds node:net to a native setImmediate. This PR does not edit net.ts. The rewrite covers its call sites, and a file-local binding takes precedence over the rewrite, so either merge order works. The two close orders in the new net.Socket test come from that PR.
Resolve runtime globals in builtin modules to the intrinsic, not globalThis #40303 resolves object-valued globals (MessagePort, Blob, process) through getOwnPropertySlot. It states that function-valued globals are out of scope. These three names use one getter each, because the public and the private name must hold one function object.

What the rewrite covers

The bundled modules of this branch have 41 private references and no bare reference: 27 @setImmediate, 2 @clearImmediate, 12 @queueMicrotask. One of the 41 is the hand-written $setImmediate in timers.promises.ts, where the module declares its own setImmediate.

module	references
`node:http2`	16
`node:net`	7
`internal/streams/iter/classic`	5
`node:inspector`	3
`internal/shared`	2
`node:timers`	2
`node:timers/promises`	2
`node:_http_common`	1
`internal/abort_listener`	1
`internal/fs/watch`	1
`ws`	1

Tests

test/js/bun/globals.test.js, new block. Each case runs a child process. Node v26.3.0 prints the expected output for every child.

case	bun 1.4.3
globals replaced after the modules are loaded	observer, abort listener and watcher lost. Calls to the replacements: 1, 1, 2
globals replaced before the modules are loaded	also `node:timers` exports the replacement, and `timers/promises.setImmediate()` never resolves
globals deleted before the modules are loaded	`ReferenceError: setImmediate is not defined`
globals replaced in an ES module	as the first case
`node:test` `mock.timers` for `setImmediate`	the `PerformanceObserver` gets nothing
`net.Socket` close, two orders	no `'close'` event
`node:http2` over TCP and over a Duplex	3 of 7 events, then the process hangs (the test kills it after 20 s)

One more case checks in process that the three public globals keep their name, length and attributes. deletable-globals-fixture.js now also deletes and assigns the three names.

The report's script prints 0 of 3 came on 1.4.3 and 3 of 3 came with this branch (5 of 5 runs).

The builtins format version and the lint

bun build --compile --bytecode parses the builtin modules of the target executable in the host's VM. JSC's lexer dereferences null for a private name that the VM does not have.
Measured with the official 1.4.2 and 1.4.3 binaries as hosts and a build of this branch as the target (--compile-executable-path). With the version field set back to 1: panic(main thread): Segmentation fault at address 0x0, exit code 139. With version 2: exit code 0, and the compiled program runs. The host does not read a section of another version.
The reader accepts only its own version, as before this PR. So a host with this change also skips the section of a 1.4.1 to 1.4.3 target. That costs something only when host and target have the same WebKit version: the target rejects bytecode from another WebKit version in any case (getWebKitBytecodeCacheVersion in ZigGlobalObject.cpp, checked by isUpToDate in JSC's CachedTypes.cpp).
test/internal/source-lints/builtins-format-version.test.ts keeps the two version constants equal. Its inventory is Bun's private names at the last version change: the rows of BunBuiltinNames.h, and the names that the code generator makes for the functions of an @internal file in src/js/builtins. It fails when a builtin module uses a newer name, or when a name of the inventory is gone. Then the fix is a version bump and --update, which refuses to run without the bump.
.github/workflows/source-lints.yml now triggers on src/js/**, because the lint reads the module sources.
The lexer defect is handed off as separate work. When a bun with that fix ships, one more version bump makes this rule and the lint unnecessary.

Behavior that changes

A tool that replaces the three globals no longer receives the immediates and microtasks of built-in modules. mock.timers.tick(), sinon's clock.tick() and similar do not run them. They run on the real event loop. Node's lib/ behaves the same: it takes these functions from timers and internal/process/task_queues when a module loads.
require("node:timers").setImmediate and .clearImmediate are the original functions even when the globals were replaced or deleted before node:timers was loaded.

Measurements

Release builds of the merge base and of this branch, linux-x64, same machine and build directory.

Binary (size): text 89,104,001 to 89,106,121 (+2,120), data 110,728 to 110,792 (+64), bss unchanged. The total is +2,184 bytes. The file grows by 4,096 bytes (one page).
Builtins section (.bun_builtins): 2,631,537 to 2,631,609 bytes (+72).
Private names: 178 to 181 rows in BunBuiltinNames.h. JS2NATIVE_COUNT is 231 in both.
Cells of one global object (heapStats().objectTypeCounts after a full collection). At startup: CustomGetterSetter 37 to 40, GetterSetter 30 and Function 385 in both. The first read of a name makes the same cells in both builds (setImmediate: 2 functions and 1 GetterSetter, the other two: 1 function each). With this PR it also frees that name's CustomGetterSetter. After the three reads the counts are equal: 37, 31 and 389.
Bytecode: BUN_JSC_dumpGeneratedBytecodes=1 for a program that calls events.addAbortListener(). The two dumps have 2,511 lines each. They differ in one identifier (queueMicrotask to PrivateSymbol.queueMicrotask) and in the source hashes of the three changed code blocks. addAbortListener has 63 instructions and 459 bytes in both.
CPU time (user plus system) for 2,000,000 operations, median of 11 rounds. Each round runs base, PR, base. The last column is the second base run against the first, which is the noise floor.

operation	base	PR	delta	base against base
`queueMicrotask(fn)`	101,880 µs	108,342 µs	+6.3%	+6.6%
`setImmediate(fn)`	580,475 µs	577,954 µs	-0.4%	+2.1%
`clearImmediate(setImmediate(fn))`	378,619 µs	337,673 µs	-10.8%	-3.9%
`events.addAbortListener(aborted, fn)`	1,030,548 µs	1,037,995 µs	+0.7%	+3.1%

Startup with an empty file, 400 alternating runs: median CPU time 8,971 µs (base) and 8,837 µs (PR), 852 minor page faults in both. With the two binaries in the other order: 8,805 µs and 8,759 µs.
The clearImmediate row and the startup numbers favor the PR by more than the noise floor. The PR adds work and removes none, so I read that as an effect of the 2 KB shift in .text, not as a gain.
perf, valgrind, strace and bloaty are not installed on this machine, and perf_event_open returns ENOENT. So there is no instruction count. The bytecode comparison is the deterministic part.

Suites run on the debug build

test/js/bun/globals.test.js (28 pass, also with the sanitizer lane's environment: exception-check validation, VM destruction on exit, leak detection), test/js/web/timers/setImmediate2.test.ts, microtask.test.js, clearImmediate-gc.test.ts, test/js/node/timers/node-timers.test.ts (24), test/js/bun/test/test-timers.test.ts (11), test/js/node/test_runner/node-test.test.ts (45), and the 35 files of test/internal/source-lints/. test/js/web/timers/setImmediate.test.js has one case that gives a child process 500 ms. A debug build needs about 600 ms to start, with or without this change.

Built and run on linux-x64 only. Windows and macOS are not run locally.

[human-review] gate passed · iteration 0 · 15 files touched

fails on main (without fix)

ASAN without fix: 8 FAILED
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/internal/source-lints/builtins-format-version.test.ts test/js/bun/globals.test.js
bun test v1.4.4 (367d939d9)

test/internal/source-lints/builtins-format-version.test.ts:
(pass) the scan finds the private names, the rewritten globals and the builtin modules [7.03ms]
 97 |       ),
 98 |       "private names of the version that are gone": inventory.privateNames.filter(name => !privateNames.has(name)),
 99 |     },
100 |     "Bump BUILTINS_FORMAT_VERSION and FORMAT_VERSION, then run " +
101 |       "`bun ./test/internal/source-lints/builtins-format-version.test.ts --update`.",
102 |   ).toEqual({
          ^
error: Bump BUILTINS_FORMAT_VERSION and FORMAT_VERSION, then run `bun ./test/internal/source-lints/builtins-format-version.test.ts --update`.

  {
-   "BUILTINS_FORMAT_VERSION (src/codegen/bundle-modules.ts)": 2,
-   "FORMAT_VERSION (src/exe_format/builtins.rs)": 2,
+   "BUILTINS_FORMAT_VERSION (src/codegen/bundle-modules.ts)": 1,
+   "FORMAT_VERSION (src/exe_format/builtins.rs)": 1,
    "private names newer than the version that
... (truncated)

release without fix: 8 FAILED
bun test v1.4.3-canary.1 (367d939d9)

test/internal/source-lints/builtins-format-version.test.ts:
(pass) the scan finds the private names, the rewritten globals and the builtin modules [0.44ms]
 97 |       ),
 98 |       "private names of the version that are gone": inventory.privateNames.filter(name => !privateNames.has(name)),
 99 |     },
100 |     "Bump BUILTINS_FORMAT_VERSION and FORMAT_VERSION, then run " +
101 |       "`bun ./test/internal/source-lints/builtins-format-version.test.ts --update`.",
102 |   ).toEqual({
          ^
error: Bump BUILTINS_FORMAT_VERSION and FORMAT_VERSION, then run `bun ./test/internal/source-lints/builtins-format-version.test.ts --update`.

  {
-   "BUILTINS_FORMAT_VERSION (src/codegen/bundle-modules.ts)": 2,
-   "FORMAT_VERSION (src/exe_format/builtins.rs)": 2,
+   "BUILTINS_FORMAT_VERSION (src/codegen/bundle-modules.ts)": 1,
+   "FORMAT_VERSION (src/exe_format/builtins.rs)": 1,
    "private names newer than the version that a builtin module uses": [],
-   "private names of the version that are gone": [],
+   "private names of the version that are gone": [
+     "clearImmediate",
+     "queueMicrotask",
+     "setImmediate",
+   ]
... (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/internal/source-lints/builtins-format-version.test.ts test/js/bun/globals.test.js
bun test v1.4.4 (367d939d9)

test/internal/source-lints/builtins-format-version.test.ts:
(pass) the scan finds the private names, the rewritten globals and the builtin modules [36.67ms]
(pass) builtin modules use only the private names that every reader of the builtins format version has [43.47ms]

test/js/bun/globals.test.js:
(pass) ERR_INVALID_THIS [29.23ms]
(pass) extendable [39.46ms]
(pass) writable [18.80ms]
(pass) name [9.18ms]
(pass) File > constructor [6.40ms]
(pass) File > constructor with empty array [5.01ms]
(pass) File > constructor with lastModified [6.22ms]
(pass) File > constructor with undefined name [5.63ms]
(pass) File > constructor throws invalid args [12.80ms]
(pass) File > constructor without new [6.12ms]
(pass) File > instanceof [7.77ms]
(pass) File > extendable [28.00ms]
(pass) globals are deletable [856.03ms]
(pass) built-in modules keep their own setImmediate, clearImmediate and queueMicrotask > with the globals replaced after
... (truncated)

release with fix: all passed
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped) in 2488ms (unchanged)
ninja: Entering directory `/workspace/bun/build/release'
[1/215] gen ErrorCode+*.h
[2/215] gen cpp.rs (cppbind)
[3/215] gen ZigGlobalObject.lut.h
Generating /workspace/bun/build/release/codegen/ZigGlobalObject.lut.h from /workspace/bun/src/jsc/bindings/ZigGlobalObject.lut.txt
[4/215] gen JS modules (bundle-modules)
Preprocess modules (16259ms)
Bundle modules (328ms)
Postprocesss modules (175ms)
Bundle Functions (733ms)
Generate Code (116ms)

[17.64s] Bundled "src/js" for production
  2614 kb
  198 internal modules
  13 native modules
  50 internal functions across 16 files
[5/212] build.rs build_script_build
[6/212] rustc bun_platform 
[7/212] rustc bun_core 
[8/212] rustc bun_safety 
[9/212] rustc bun_zlib_sys 
[10/212] rustc bun_output 
[11/212] rustc bun_brotli 
[12/212] rustc bun_zstd 
[13/212] rustc bun_boringssl_sys 
[14/212] rustc bun_cares_sys 
[15/212] rustc bun_picohttp 
[16/212] rustc bun_base64 
[17/212] rustc bun_ptr 
[18/212] rustc bun_valkey 
[19/212] rustc bun_errno 
[20/212] rustc bun_clap 
[21/212] rustc bun_lsquic_sys 
[22/212] rustc bun_tcc_
... (truncated)

diff hotspot

.github/workflows/source-lints.yml                 |   4 +-
 src/codegen/bundle-modules.ts                      |   3 +-
 src/codegen/replacements.ts                        |   3 +
 src/exe_format/builtins.rs                         |   2 +-
 src/js/builtins.d.ts                               |   1 +
 src/js/builtins/BunBuiltinNames.h                  |   3 +
 src/js/node/timers.promises.ts                     |   2 +-
 src/jsc/bindings/ZigGlobalObject.cpp               |  48 ++++
 src/jsc/bindings/ZigGlobalObject.lut.txt           |   6 +-
 src/jsc/bindings/node/NodeTimers.cpp               |   5 +
 src/jsc/bindings/node/NodeTimers.h                 |   2 +
 .../builtins-format-version.inventory.json         | 186 ++++++++++++++
 .../source-lints/builtins-format-version.test.ts   | 108 ++++++++
 test/js/bun/deletable-globals-fixture.js           |  14 +-
 test/js/bun/globals.test.js                        | 275 ++++++++++++++++++++-
 15 files changed, 652 insertions(+), 10 deletions(-)

gate history · 1 passed · 0 rejected · iteration 0

evidence per changed file

file                                                      reads  edits  tests
.github/workflows/source-lints.yml                            2      2     61
src/codegen/bundle-modules.ts                                 3      2     62
src/codegen/replacements.ts                                   4      2     61
src/exe_format/builtins.rs                                    2      2     62
src/js/builtins.d.ts                                          2      2     61
src/js/builtins/BunBuiltinNames.h                             2      2     64
src/js/node/timers.promises.ts                                2      2     61
src/jsc/bindings/ZigGlobalObject.cpp                          6      3     63
src/jsc/bindings/ZigGlobalObject.lut.txt                      2      2     62
src/jsc/bindings/node/NodeTimers.cpp                          3      1     61
src/jsc/bindings/node/NodeTimers.h                            1      2     61
…nal/source-lints/builtins-format-version.inventory.json      0      0     62
…t/internal/source-lints/builtins-format-version.test.ts      2      6     15
test/js/bun/deletable-globals-fixture.js                      0      0     62
test/js/bun/globals.test.js                                   6      6     50

@name

…src/js to private names Built-in modules called the public globals at call time. A test's fake timers (sinon, vitest, node:test's mock.timers) or happy-dom replace those globals in JS, so an http2 session's close, a PerformanceObserver delivery, events.addAbortListener() and fs.watch()'s 'close' were handed to the replacement and never ran. The three names join globalsToPrefix, so the builtin bundler rewrites every bare reference in src/js to a private @name. Each private name is a lazy slot on the global object: the first read creates the realm's one function and replaces the accessor with it. The public globals are property callbacks that return the same object, so node:timers and the globals stay identical. The builtins section format version goes from 1 to 2: an older bun that compiles these sources for `bun build --compile --bytecode` does not know the new private names.

… builtins format version The define also covers the six setImmediate sites of node:net, so the close-order cases of #44366 pass with net.ts untouched. They are added to the block in globals.test.js, adapted to its helper. builtins-format-version.test.ts holds BUILTINS_FORMAT_VERSION and FORMAT_VERSION equal and pins the Bun private names that builtin modules use. A module that starts to use another one fails the lint until both versions are bumped. The source-lints workflow now also runs for a change under src/js. Co-authored-by: Peter Steinberger <steipete@gmail.com>

… tests that fail without hanging Co-authored-by: Peter Steinberger <steipete@gmail.com>

robobun · 2026-10-10T12:07:24Z

^{Updated 9:35 AM PT - Oct 10th, 2026}

✅ @robobun, your commit 7192dd8a2f476befdb6091f4120eb5ae00c4d6cd passed in Build #124325! 🎉

🧪 To try this PR locally:

bunx bun-pr 44917

That installs a local version of the PR into your bun-44917 executable, so you can run:

bun-44917 --bun

robobun · 2026-10-10T12:07:28Z

Status: ready for review. The review comments are answered, and 912e242 and 6068cbc have the ones that led to a change (all in test files).

Reproduction: the script from the report prints 0 of 3 came on bun 1.4.3 (5 of 5 runs) and 3 of 3 came with this branch (5 of 5 runs). Node v26.3.0 prints 3 of 3 came. test/js/bun/globals.test.js has 7 new cases that fail on bun 1.4.3 and pass with this branch.

robobun · 2026-10-10T12:07:51Z

@dylan-conway a question about #40303, because both PRs extend globalsToPrefix.

#40303 leaves function-valued globals out of scope and resolves a private name through getOwnPropertySlot. This PR adds three function-valued globals with one lazy getter each, because the public and the private name must hold one function object (node:timers exports it).

If Resolve runtime globals in builtin modules to the intrinsic, not globalThis #40303 merges first, I will move these three names onto its lookup. Is that the shape you want, or do you prefer them in Resolve runtime globals in builtin modules to the intrinsic, not globalThis #40303 from the start?
One thing that also applies to Resolve runtime globals in builtin modules to the intrinsic, not globalThis #40303: a builtin module that uses a new private name needs a bump of the builtins format version. bun 1.4.2 and 1.4.3 segfault in bun build --compile --bytecode for such a target otherwise (details under "The builtins format version and the lint" in the Notes of this PR).

coderabbitai · 2026-10-10T12:56:21Z

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test/js/bun/globals.test.js

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Walkthrough

The change adds private scheduling globals for built-in modules and updates the built-ins format version to 2. It adds format-version inventory checks and tests built-in behavior when public scheduling globals are replaced or deleted.

Changes

Private Scheduling Globals

Layer / File(s)	Summary
Format and private-name contracts `src/codegen/bundle-modules.ts`, `src/exe_format/builtins.rs`, `src/codegen/replacements.ts`, `src/js/builtins/BunBuiltinNames.h`, `src/js/builtins.d.ts`, `test/internal/source-lints/builtins-format-version.*`, `.github/workflows/source-lints.yml`	The writer and reader format versions change to 2. The private-name declarations and inventory include `clearImmediate`, `queueMicrotask`, and `setImmediate`. The test checks format-version and private-name consistency, and the workflow path filters cover `src/js/**`.
Scheduling global registration `src/jsc/bindings/ZigGlobalObject.cpp`, `src/jsc/bindings/ZigGlobalObject.lut.txt`, `src/jsc/bindings/node/NodeTimers.cpp`, `src/jsc/bindings/node/NodeTimers.h`	The global object registers private scheduling functions as lazy, read-only, non-deletable accessors. The lookup table and `clearImmediate` function factory are updated.
Built-in use and runtime validation `src/js/node/timers.promises.ts`, `test/js/bun/deletable-globals-fixture.js`, `test/js/bun/globals.test.js`	The timer-promises implementation captures `$setImmediate`. Tests cover built-in behavior when public scheduling globals are replaced or deleted, and check the public globals’ names, arity, and property attributes.

Priority: ➖ Normal

Merge Risk: ⚪ Minimal · up to 7192d

No actionable merge-blocking issue is established by the supplied evidence. Merge after normal checks.

Pre-merge checks | 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.
Description check		The description clearly explains the problem, implementation, behavior changes, compatibility impact, and verification results. It does not use the template headings exactly, but it provides the requi…
Title check		The title is concise, specific, and accurately identifies the main change: resolving setImmediate, clearImmediate, and queueMicrotask through private names in built-in modules.

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Actionable comments posted: 2

🪄 Fix CodeRabbit comments on this PR

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Inline comments:
Review comments at @test/js/bun/globals.test.js:
- Line 213: Update the built-in modules test suite to use concurrent execution
via describe.concurrent, keeping the existing isolated subprocess cases and
assertions unchanged.
- Line 455: Remove the per-test timeout argument from the callback invocation
identified by `}, 30_000);`; keep the child-process `timeout: 20_000` option
unchanged.

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📒 Files selected for processing (15)

.github/workflows/source-lints.yml
src/codegen/bundle-modules.ts
src/codegen/replacements.ts
src/exe_format/builtins.rs
src/js/builtins.d.ts
src/js/builtins/BunBuiltinNames.h
src/js/node/timers.promises.ts
src/jsc/bindings/ZigGlobalObject.cpp
src/jsc/bindings/ZigGlobalObject.lut.txt
src/jsc/bindings/node/NodeTimers.cpp
src/jsc/bindings/node/NodeTimers.h
test/internal/source-lints/builtins-format-version.inventory.json
test/internal/source-lints/builtins-format-version.test.ts
test/js/bun/deletable-globals-fixture.js
test/js/bun/globals.test.js

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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.

…private names in the format-version lint

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Actionable comments posted: 1

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Review comments at @test/js/bun/globals.test.js:
- Around line 325-326: Change the three tests that load node:test, node:net, and
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test/internal/source-lints/builtins-format-version.test.ts
test/js/bun/globals.test.js

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claude

Code review found no issues

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robobun · 2026-10-11T03:06:19Z

This PR and #44907 both change FORMAT_VERSION and BUILTINS_FORMAT_VERSION to 2, so the second one to merge has a conflict there.

#44907 adds an engine stamp to the header of the builtins section: a hash of the WebKit version and of the private names that BunBuiltinNames.h registers. A bun compiles the internal modules of another executable only if that executable has the same stamp. A new row in BunBuiltinNames.h changes the stamp, so a new private name needs no new format version.

If Builtins section format 2: an engine stamp says which buns compile its modules #44907 merges first, this PR needs no change to the two constants, and it does not need builtins-format-version.test.ts, the inventory, or the source-lints.yml change. The three rows in BunBuiltinNames.h are enough.
If this PR merges first, Builtins section format 2: an engine stamp says which buns compile its modules #44907 takes format version 3 and removes the lint and the inventory.

robobun and others added 3 commits October 10, 2026 10:52

Review fixes: exception idiom, hygienic getter macro, inventory lint,…

f20efaf

… tests that fail without hanging Co-authored-by: Peter Steinberger <steipete@gmail.com>

robobun assigned Jarred-Sumner Oct 10, 2026

github-actions Bot added the claude label Oct 10, 2026

robobun mentioned this pull request Oct 10, 2026

bun:test: keep built-in modules' own timers out of fake timers (internal/timers) #37987

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robobun marked this pull request as ready for review October 10, 2026 12:50

robobun requested a review from alii as a code owner October 10, 2026 12:50

coderabbitai Bot reviewed Oct 10, 2026

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Comment thread test/js/bun/globals.test.js

Comment thread test/js/bun/globals.test.js Outdated

claude Bot reviewed Oct 10, 2026

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Comment thread src/jsc/bindings/ZigGlobalObject.cpp

Comment thread src/exe_format/builtins.rs

Comment thread test/internal/source-lints/builtins-format-version.test.ts Outdated

Comment thread test/js/bun/globals.test.js Outdated

tests: run the replaced-globals matrix concurrently, count generated …

912e242

…private names in the format-version lint

coderabbitai Bot reviewed Oct 10, 2026

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Comment thread test/js/bun/globals.test.js Outdated

claude Bot reviewed Oct 10, 2026

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tests: run the three heavier children as a second concurrent group

6068cbc

claude Bot reviewed Oct 10, 2026

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ci: retrigger

7192dd8

robobun mentioned this pull request Oct 11, 2026

Builtins section format 2: an engine stamp says which buns compile its modules #44907

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robobun mentioned this pull request Oct 20, 2026

node: $toClass installs the prototype of built-in constructors; EventEmitter reads it with $getPrototypeOf #46197

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robobun commented Oct 10, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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