### What does this PR do?
Previously, reactFastRefresh was silently ignored when target was not
'browser', even when explicitly enabled. This was confusing as there was
no warning or error.
This change removes the `target == .browser` check, trusting explicit
user intent. If users enable reactFastRefresh with a non-browser target,
the transform will now be applied. If `$RefreshReg$` is not defined at
runtime, it will fail fast with a clear error rather than silently doing
nothing.
Use case: Terminal UIs (like [termcast](https://termcast.app)) need
React Fast Refresh with target: 'bun' for hot reloading in non-browser
environments.
### How did you verify your code works?
Updated existing test removing target browser
## Summary
- Add `_idleStart` property (getter/setter) to the Timeout object
returned by `setTimeout()` and `setInterval()`
- The property returns a monotonic timestamp (in milliseconds)
representing when the timer was created
- This mimics Node.js's behavior where `_idleStart` is the libuv
timestamp at timer creation time
## Test plan
- [x] Verified test fails with `USE_SYSTEM_BUN=1 bun test
test/regression/issue/25639.test.ts`
- [x] Verified test passes with `bun bd test
test/regression/issue/25639.test.ts`
- [x] Manual verification:
```bash
# Bun with fix - _idleStart exists
./build/debug/bun-debug -e "const t = setTimeout(() => {}, 0);
console.log('_idleStart' in t, typeof t._idleStart); clearTimeout(t)"
# Output: true number
# Node.js reference - same behavior
node -e "const t = setTimeout(() => {}, 0); console.log('_idleStart' in
t, typeof t._idleStart); clearTimeout(t)"
# Output: true number
```
Closes#25639🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
## Summary
- Fixes handler context not being restored after minifying nested CSS
rules
- Adds regression test for the issue
## Test plan
- [x] Test fails with `USE_SYSTEM_BUN=1 bun test
test/regression/issue/25794.test.ts`
- [x] Test passes with `bun bd test test/regression/issue/25794.test.ts`
Fixes#25794🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Fixes#25862
### What does this PR do?
When a client sends pipelined data immediately after CONNECT request
headers in the same TCP segment, Bun now properly delivers this data to
the `head` parameter of the 'connect' event handler, matching Node.js
behavior.
This enables compatibility with Cap'n Proto's KJ HTTP library used by
Cloudflare's workerd runtime, which pipelines RPC data after CONNECT.
### How did you verify your code works?
<img width="694" height="612" alt="CleanShot 2026-01-09 at 15 30 22@2x"
src="https://github.com/user-attachments/assets/3ffe840e-1792-429c-8303-d98ac3e6912a"
/>
Tests
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
Fixes#25869
Two fixes to enable `jest.useFakeTimers()` to work with
`@testing-library/react` and `@testing-library/user-event`:
- Set `setTimeout.clock = true` when fake timers are enabled.
testing-library/react's `jestFakeTimersAreEnabled()` checks for this
property to determine if `jest.advanceTimersByTime()` should be called
when draining the microtask queue. Without this, testing-library never
advances timers.
- Make `advanceTimersByTime(0)` fire `setTimeout(fn, 0)` timers.
`setTimeout(fn, 0)` is internally scheduled with a 1ms delay per HTML
spec. Jest/testing-library expect `advanceTimersByTime(0)` to fire such
"immediate" timers, but we were advancing by 0ms so they never fired.
## Test plan
- [x] All 30 existing fake timer tests pass
- [x] New regression test validates both fixes
- [x] Original user-event reproduction now works (test completes instead
of hanging)
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Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
## Summary
- Fixes#25903 - `Bun.write()` mode option ignored when copying from
`Bun.file()`
- The destination file now correctly uses the specified `mode` option
instead of default permissions
- Works on Linux (via open flags), macOS (chmod after clonefile), and
Windows (chmod after copyfile)
## Test plan
- [x] Added regression test in `test/regression/issue/25903.test.ts`
- [x] Test passes with `bun bd test test/regression/issue/25903.test.ts`
- [x] Test fails with `USE_SYSTEM_BUN=1 bun test
test/regression/issue/25903.test.ts` (verifies the bug exists)
## Changes
- `src/bun.js/webcore/Blob.zig`: Add `mode` field to `WriteFileOptions`
and parse from options
- `src/bun.js/webcore/blob/copy_file.zig`: Use `destination_mode` in
`CopyFile` struct and `doOpenFile`
- `packages/bun-types/bun.d.ts`: Add `mode` option to BunFile copy
overloads
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---------
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Fixes#25716
Adds support for a `reactFastRefresh: boolean` option in the `Bun.build`
JavaScript API, matching the existing `--react-fast-refresh` CLI flag.
```ts
const result = await Bun.build({
reactFastRefresh: true,
entrypoints: ["src/App.tsx"],
});
```
When enabled, the bundler adds React Fast Refresh transform code
(`$RefreshReg$`, `$RefreshSig$`) to the output.
Closes#8254
Fixes a data corruption bug in `Bun.write()` where files larger than 2GB
would have chunks skipped resulting in corrupted output with missing
data.
The `doWriteLoop` had an issue where it would essentially end up
offsetting twice every 2GB chunks:
- it first sliced the buffer by `total_written`:
```remain = remain[@min(this.total_written, remain.len)..]```
- it would then increment `bytes_blob.offset`:
`this.bytes_blob.offset += @truncate(wrote)`
but because `sharedView()` already uses the blob offset `slice_ = slice_[this.offset..]` it would end up doubling the offset.
In a local reproduction writing a 16GB file with each 2GB chunk filled with incrementing values `[1, 2, 3, 4, 5, 6, 7, 8]`, the buggy version produced: `[1, 3, 5, 7, …]`, skipping every other chunk.
The fix is to simply remove the redundant manual offset and rely only on `total_written` to track write progress.
## Summary
- Fixes dead code elimination producing invalid syntax like `{ ...a, x:
}` when simplifying empty objects in spread contexts
- The issue was that `simplifyUnusedExpr` and `joinAllWithCommaCallback`
could return `E.Missing` instead of `null` to indicate "no side effects"
- Added checks to return `null` when the result is `E.Missing`
Fixes#25609
## Test plan
- [x] Added regression test that fails on v1.3.5 and passes with fix
- [x] `bun bd test test/regression/issue/25609.test.ts` passes
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Co-authored-by: Claude <noreply@anthropic.com>
## Summary
Fix several memory leaks in the compression libraries:
- **NativeBrotli/NativeZstd reset()** - Each call to `reset()` allocated
a new encoder/decoder without freeing the previous one
- **NativeBrotli/NativeZstd init() error paths** - If `setParams()`
failed after `stream.init()` succeeded, the instance was leaked
- **NativeZstd init()** - If `setPledgedSrcSize()` failed after context
creation, the context was leaked
- **ZlibCompressorArrayList** - After `deflateInit2_()` succeeded, if
`ensureTotalCapacityPrecise()` failed with OOM, zlib internal state was
never freed
- **NativeBrotli close()** - Now sets state to null to prevent potential
double-free (defensive)
- **LibdeflateState** - Added `deinit()` for API consistency
## Test plan
- [x] Added regression test that calls `reset()` 100k times and measures
memory growth
- [x] Test shows memory growth dropped from ~600MB to ~10MB for Brotli
- [x] Verified no double-frees by tracing code paths
- [x] Existing zlib tests pass (except pre-existing timeout in debug
build)
Before fix (system bun 1.3.3):
```
Memory growth after 100000 reset() calls: 624.38 MB (BrotliCompress)
Memory growth after 100000 reset() calls: 540.63 MB (BrotliDecompress)
```
After fix:
```
Memory growth after 100000 reset() calls: 11.84 MB (BrotliCompress)
Memory growth after 100000 reset() calls: 0.16 MB (BrotliDecompress)
```
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Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
Fixes#24593 - WebSocket segfault on Windows when publishing large
messages with `perMessageDeflate: true`.
Also fixes#21028 (duplicate issue).
Also closes#25457 (alternative PR).
**Root cause:**
On Windows, the C++ code was compiled against system zlib headers
(1.3.1) but linked against Bun's vendored Cloudflare zlib (1.2.8).
This version mismatch caused `deflateInit2()` to return
`Z_VERSION_ERROR` (-6), leaving the deflate stream in an invalid state.
All subsequent `deflate()` calls returned `Z_STREAM_ERROR` (-2),
producing zero output, which then caused an integer underflow when
subtracting the 4-byte trailer → segfault in memcpy.
**Fix:**
Add `${VENDOR_PATH}/zlib` to the C++ include paths in
`cmake/targets/BuildBun.cmake`. This ensures the vendored zlib headers
are found before system headers, maintaining header/library version
consistency.
This is a simpler alternative to #25457 which worked around the issue by
using libdeflate exclusively.
## Test plan
- [x] Added regression test `test/regression/issue/24593.test.ts` with 4
test cases:
- Large ~109KB JSON message publish (core reproduction)
- Multiple rapid publishes (buffer corruption)
- Broadcast to multiple subscribers
- Messages at CORK_BUFFER_SIZE boundary (16KB)
- [x] Tests pass on Windows (was crashing before fix)
- [x] Tests pass on macOS
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---------
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## Summary
Fixes#13316Fixes#18275
Running `bunx cowsay ""` (or any package with an empty string argument)
on Windows caused a panic. Additionally, `bunx concurrently "command
with spaces"` was splitting quoted arguments incorrectly.
**Repro #13316:**
```bash
bunx cowsay ""
# panic(main thread): reached unreachable code
```
**Repro #18275:**
```bash
bunx concurrently "bun --version" "bun --version"
# Only runs once, arguments split incorrectly
# Expected: ["bun --version", "bun --version"]
# Actual: ["bun", "--version", "bun", "--version"]
```
## Root Cause
The bunx fast path on Windows bypasses libuv and calls `CreateProcessW`
directly to save 5-12ms. The command line building logic had two issues:
1. **Empty strings**: Not quoted at all, resulting in invalid command
line
2. **Arguments with spaces**: Not quoted, causing them to be split into
multiple arguments
## Solution
Implement Windows command-line argument quoting using libuv's proven
algorithm:
- Port of libuv's `quote_cmd_arg` function (process backwards + reverse)
- Empty strings become `""`
- Strings with spaces/tabs/quotes are wrapped in quotes
- Backslashes before quotes are properly escaped per Windows rules
**Why not use libuv directly?**
- Normal `Bun.spawn()` uses `uv_spawn()` which handles quoting
internally
- bunx fast path bypasses libuv to save 5-12ms (calls `CreateProcessW`
directly)
- libuv's `quote_cmd_arg` is a static function (not exported)
- Solution: port the algorithm to Zig
## Test Plan
- [x] Added regression test for empty strings (#13316)
- [x] Added regression test for arguments with spaces (#18275)
- [x] Verified system bun (v1.3.3) fails both tests
- [x] Verified fix passes both tests
- [x] Implementation based on battle-tested libuv algorithm
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---------
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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
- Fixes `url.domainToASCII` and `url.domainToUnicode` to return empty
string instead of throwing `TypeError` when given invalid domains
- Per Node.js docs: "if `domain` is an invalid domain, the empty string
is returned"
## Test plan
- [x] Run `bun bd test test/regression/issue/24191.test.ts` - all 2
tests pass
- [x] Verify tests fail with system Bun (`USE_SYSTEM_BUN=1`) to confirm
fix validity
- [x] Manual verification: `url.domainToASCII('xn--iñvalid.com')`
returns `""`
## Example
Before (bug):
```
$ bun -e "import url from 'node:url'; console.log(url.domainToASCII('xn--iñvalid.com'))"
TypeError: domainToASCII failed
```
After (fixed):
```
$ bun -e "import url from 'node:url'; console.log(url.domainToASCII('xn--iñvalid.com'))"
(empty string output)
```
Closes#24191🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Fixes#25398
### What does this PR do?
Fixes a bug where object expressions with spread properties and nullish
coalescing to empty objects (e.g., `k?.x ?? {}`) would produce invalid
JavaScript output like `k?.x ?? ` (missing `{}`).
### Root Cause
In `src/ast/SideEffects.zig`, the `simplifyUnusedExpr` function handles
unused object expressions with spread properties. When simplifying
property values:
1. The code creates a mutable copy `prop` from the original `prop_`
2. When a property value is simplified (e.g., `k?.x ?? {}` → `k?.x`), it
updates `prop.value`
3. **Bug:** The code then wrote back `prop_` (the original) instead of
`prop` (the modified copy)
Because `simplifyUnusedExpr` mutates the AST in place when handling
nullish coalescing (setting `bin.right` to empty), the original `prop_`
now contained an expression with `bin.right` as an empty/missing
expression, resulting in invalid output.
### How did you verify your code works?
- Added regression test in `test/regression/issue/25398.test.ts`
- Verified the original reproduction case passes
- Verified existing CommonJS tests continue to pass
- Verified test fails with system bun and passes with the fix
## Summary
- Change the size header in embedded Mach-O and PE sections from `u32`
(4 bytes) to `u64` (8 bytes)
- Ensures the data payload starts at an 8-byte aligned offset, which is
required for the bytecode cache
## Test plan
- [x] Test standalone compilation on macOS
- [ ] Test standalone compilation on Windows
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## Summary
- Fix regression where `new Bun.FFI.CString(ptr)` throws "function is
not a constructor"
- Pass the same function as both call and constructor callbacks for
CString
## Root Cause
PR #24910 replaced `jsc.createCallback` with `jsc.JSFunction.create` for
all FFI functions. However, `JSFunction.create` doesn't allow
constructor calls by default (it uses `callHostFunctionAsConstructor`
which throws). The old `createCallback` used `JSFFIFunction` which
allowed the same function to be called with `new`.
## Fix
Pass the same function as both the `implementation` and `constructor`
option to `JSFunction.create` for CString specifically. This allows `new
CString(ptr)` to work while keeping the refactoring from #24910.
Additionally, the `bun:ffi` module now replaces `Bun.FFI.CString` with
the proper JS CString class after loading, so users get the full class
with `.ptr`, `.byteOffset`, etc. properties.
## Test plan
- [x] Added regression test `test/regression/issue/25231.test.ts`
- [x] Test fails with `USE_SYSTEM_BUN=1` (v1.3.3), passes with fix
- [x] Verified reproduction case from issue works
Fixes#25231🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
- Added null check for `sourceOrigin` before accessing its URL in
`jest.mock()`
- When `callerSourceOrigin()` returns null (e.g., when called with
invalid arguments), the code now safely returns early instead of
crashing
## Test plan
- [x] Added regression test `test/regression/issue/ENG-24434.test.ts`
- [x] `bun bd test test/regression/issue/ENG-24434.test.ts` passes
Fixes ENG-24434
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## Summary
Fixes `TLSSocket.isSessionReused()` to use BoringSSL's
`SSL_session_reused()` API instead of incorrectly checking if a session
was set.
The previous implementation returned `!!this[ksession]` which would
return `true` if `setSession()` was called, even if the session wasn't
actually reused by the SSL layer. This fix correctly uses the native SSL
API like Node.js does.
## Changes
- Added native `isSessionReused` function in Zig that calls
`SSL_session_reused()`
- Updated `TLSSocket.prototype.isSessionReused` to use the native
implementation
- Added regression tests
## Test plan
- [x] `bun bd test test/regression/issue/25190.test.ts` passes
- [x] `bun bd test test/js/node/tls/node-tls-connect.test.ts` passes
Fixes#25190🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
- Fixes `assert.deepStrictEqual()` to properly compare Number and
Boolean wrapper objects
- Previously, `new Number(1)` and `new Number(2)` were incorrectly
considered equal because they have no enumerable properties
- Now correctly extracts and compares internal values using
`JSC::sameValue()`, then falls through to check own properties
## Test plan
- [x] Run `bun bd test test/regression/issue/24045.test.ts` - all 6
tests pass
- [x] Verify tests fail with system Bun (`USE_SYSTEM_BUN=1`) to confirm
fix validity
- [x] Verified behavior matches Node.js exactly (see table below)
## Node.js Compatibility
| Test Case | Node.js | Bun |
|-----------|---------|-----|
| Different Number values (`new Number(1)` vs `new Number(2)`) | throws
| throws |
| Same Number values (`new Number(1)` vs `new Number(1)`) | equal |
equal |
| 0 vs -0 (`new Number(0)` vs `new Number(-0)`) | throws | throws |
| NaN equals NaN (`new Number(NaN)` vs `new Number(NaN)`) | equal |
equal |
| Different Boolean values (`new Boolean(true)` vs `new Boolean(false)`)
| throws | throws |
| Same Boolean values | equal | equal |
| Number wrapper vs primitive (`new Number(1)` vs `1`) | throws | throws
|
| Number vs Boolean wrapper | throws | throws |
| Same value, different own properties | throws | throws |
| Same value, same own properties | equal | equal |
| Different own property values | throws | throws |
## Example
Before (bug):
```javascript
assert.deepStrictEqual(new Number(1), new Number(2)); // passes incorrectly
```
After (fixed):
```javascript
assert.deepStrictEqual(new Number(1), new Number(2)); // throws AssertionError
```
Closes#24045🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
## Summary
- Implements the `%j` format specifier for `console.log` and related
console methods
- `%j` outputs the JSON stringified representation of the value
- Previously, `%j` was not recognized and was left as literal text in
the output
## Test plan
- [x] Run `bun bd test test/regression/issue/24234.test.ts` - all 5
tests pass
- [x] Verify tests fail with system Bun (`USE_SYSTEM_BUN=1`) to confirm
fix validity
- [x] Manual verification: `console.log('%j', {foo: 'bar'})` outputs
`{"foo":"bar"}`
## Example
Before (bug):
```
$ bun -e "console.log('%j %s', {foo: 'bar'}, 'hello')"
%j [object Object] hello
```
After (fixed):
```
$ bun -e "console.log('%j %s', {foo: 'bar'}, 'hello')"
{"foo":"bar"} hello
```
Closes#24234🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
- Fix `bun publish --help` showing incorrect `--dry-run` description
("Don't install anything" → "Perform a dry run without making changes")
- The `--dry-run` flag is in a shared params array used by multiple
commands, so the new generic message works for all of them
Fixes#24806
## Test plan
- [x] Verify `bun publish --help` shows "Perform a dry run without
making changes" for --dry-run
- [x] Regression test added that validates the correct help text is
shown
- [x] Test passes with debug build, fails with system bun (validating it
tests the right thing)
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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
- Make `Http2Server.setTimeout()` and `Http2SecureServer.setTimeout()`
return `this` to enable method chaining
- Matches Node.js behavior where `server.setTimeout(1000).listen()`
works
Fixes#24924
## Test plan
- [x] Test that `Http2Server.setTimeout()` returns server instance
- [x] Test that `Http2SecureServer.setTimeout()` returns server instance
- [x] Test method chaining works (e.g.,
`server.setTimeout(1000).close()`)
- [x] Tests pass with debug build, fail with system bun
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Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
- Fix debug assertion failure in `JSWrappingFunction` when
`expect.extend()` is called with objects containing non-`JSFunction`
callables
- The crash occurred because `jsCast<JSFunction*>` was used, which
asserts the value inherits from `JSFunction`, but callable class
constructors (like `Expect`) inherit from `InternalFunction` instead
## Changes
- Change `JSWrappingFunction` to store `JSObject*` instead of
`JSFunction*`
- Use `jsDynamicCast` instead of `jsCast` in `getWrappedFunction`
- Use `getObject()` instead of `jsCast` in `create()`
## Reproduction
```js
const jest = Bun.jest();
jest.expect.extend(jest);
```
Before fix (debug build):
```
ASSERTION FAILED: !from || from->JSCell::inherits(std::remove_pointer<To>::type::info())
JSCast.h(40) : To JSC::jsCast(From *) [To = JSC::JSFunction *, From = JSC::JSCell]
```
After fix: Properly throws `TypeError: expect.extend: 'jest' is not a
valid matcher`
## Test plan
- [x] Added regression test
`test/regression/issue/fuzzer-ENG-22942.test.ts`
- [x] Existing `expect-extend.test.js` tests pass (27 tests)
- [x] Build succeeds
Fixes ENG-22942
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## Summary
Fixes#23292
`fs.access()` and `fs.accessSync()` threw EUNKNOWN (-134) when checking
named pipes on Windows (paths like `\.\pipe\name`), but Node.js worked
fine.
**Repro:**
```ts
// Server creates pipe at \.\pipe\bun-test
import net from 'net';
const server = net.createServer();
server.listen('\\.\pipe\bun-test');
// Client tries to check if pipe exists
import fs from 'fs';
fs.accessSync('\\.\pipe\bun-test', fs.constants.F_OK);
// Error: EUNKNOWN: unknown error, access '\.\pipe\bun-test'
```
## Root Cause
The `osPathKernel32` function normalizes paths before passing to Windows
APIs. The normalization logic treats a single `.` as a "current
directory" component and removes it, so `\.\pipe\name` incorrectly
became `\pipe\name` - an invalid path.
## Solution
Detect Windows device paths (starting with `\.\` or `\?\`) and skip
normalization for these special paths, preserving the device prefix.
## Test Plan
- [x] Added regression test `test/regression/issue/23292.test.ts`
- [x] Test fails with system bun (v1.3.3): 3 failures (EUNKNOWN)
- [x] Test passes with fix: 4 pass
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Co-authored-by: Claude <noreply@anthropic.com>
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## Summary
Fixes a crash (ENG-22243) where calling class constructors marked with
`call: false` would create invalid instances instead of throwing an
error.
## Root Cause
When a class definition has `call: false` (like `Bun.RedisClient`), the
code generator was still allowing the constructor to be invoked without
`new`. This created invalid instances that caused a buffer overflow
during garbage collection.
## The Fix
Modified `src/codegen/generate-classes.ts` to properly check the `call`
property:
- When `call: false`: throws `TypeError: Class constructor X cannot be
invoked without 'new'`
- When `call: true`: behaves as before, allowing construction without
`new`
## Test Plan
- [x] Added regression test in `test/regression/issue/22243.test.ts`
- [x] Test fails with system bun (has the bug)
- [x] Test passes with fixed build
- [x] Verified `Bun.RedisClient()` now throws proper error
- [x] Verified `new Bun.RedisClient()` still works
## Before
```bash
$ bun -e "Bun.RedisClient()"
# Creates invalid instance, no error
```
## After
```bash
$ bun -e "Bun.RedisClient()"
TypeError: Class constructor RedisClient cannot be invoked without 'new'
```
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
### What does this PR do?
Fixes `bun pm ls --all` crash with unresolved optional peer
dependencies.
Fixes `bun pm ls` crash with empty lockfiles.
Fixes#24502
### How did you verify your code works?
Added a test for both crashes
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
Fixes https://github.com/oven-sh/bun/issues/24385
### How did you verify your code works?
Confirmed that the test added in the first commit fails on mainline
`bun` and is fixed in this PR.
---------
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Fixes#23865, Fixes ENG-21446
Previously, a termination exception would be thrown. We didn't handle it
properly and eventually it got caught by a `catch @panic()` handler.
Now, no termination exception is thrown.
```
drainMicrotasksWithGlobal calls JSC__JSGlobalObject__drainMicrotasks
JSC__JSGlobalObject__drainMicrotasks returns m_terminationException
-> drainMicrotasksWithGlobal
-> event_loop.zig:exit, which catches the error and discards it
-> ...
```
For workers, we will need to handle termination exceptions in this
codepath.
~~Previously, it would see the exception, call
reportUncaughtExceptoinAtEventLoop, but the exception would still
survive and return out from the catch scope. You're not supposed to
still have an exception signaled at the exit of a catch scope. Exception
checker may not have caught it because maybe the branch wasn't taken.~~
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
Fixes#24387
### How did you verify your code works?
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Marko Vejnovic <marko@bun.com>
## Summary
Fixes incorrect JWK "d" field length for exported elliptic curve private
keys. The "d" field is now correctly padded to ensure RFC 7518
compliance.
## Problem
When exporting EC private keys to JWK format, the "d" field would
sometimes be shorter than required by RFC 7518 because
`convertToBytes()` doesn't pad the result when the BIGNUM has leading
zeros. This caused incompatibility with Chrome's strict validation,
though Node.js and Firefox would accept the malformed keys.
Expected lengths per RFC 7518:
- P-256: 32 bytes → 43 base64url characters
- P-384: 48 bytes → 64 base64url characters
- P-521: 66 bytes → 88 base64url characters
## Solution
Changed `src/bun.js/bindings/webcrypto/CryptoKeyECOpenSSL.cpp:420` to
use `convertToBytesExpand(privateKey, keySizeInBytes)` instead of
`convertToBytes(privateKey)`, ensuring the private key is padded with
leading zeros when necessary. This matches the behavior already used for
the x and y public key coordinates.
## Test plan
- ✅ Added regression test in `test/regression/issue/24399.test.ts` that
generates multiple keys for each curve and verifies correct "d" field
length
- ✅ Test fails with `USE_SYSTEM_BUN=1 bun test` (reproduces the bug)
- ✅ Test passes with `bun bd test` (verifies the fix)
- ✅ Existing crypto tests pass
Fixes#24399🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
Adds `"configVersion"` to bun.lock(b). The version will be used to keep
default settings the same if they would be breaking across bun versions.
fixes ENG-21389
fixes ENG-21388
### How did you verify your code works?
TODO:
- [ ] new project
- [ ] existing project without configVersion
- [ ] existing project with configVersion
- [ ] same as above but with bun.lockb
- [ ] configVersion@0 defaults to hoisted linker
- [ ] new projects use isolated linker
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
## Summary
Fixes#24147
- Fixed EventEmitter crash when `removeAllListeners()` is called from
within an event handler while a `removeListener` meta-listener is
registered
- Added undefined check before iterating over listeners array to match
Node.js behavior
- Added comprehensive regression tests
## Bug Description
When `removeAllListeners(type)` was called:
1. From within an event handler
2. While a `removeListener` meta-listener was registered
3. For an event type with no listeners
It would crash with: `TypeError: undefined is not an object (evaluating
'this._events')`
## Root Cause
The `removeAllListeners` function tried to access `listeners.length`
without checking if `listeners` was defined first. When called with an
event type that had no listeners, `events[type]` returned `undefined`,
causing the crash.
## Fix
Added a check `if (listeners !== undefined)` before iterating, matching
the behavior in Node.js core:
https://github.com/nodejs/node/blob/main/lib/events.js#L768
## Test plan
- ✅ Created regression test in `test/regression/issue/24147.test.ts`
- ✅ Verified test fails with `USE_SYSTEM_BUN=1 bun test` (reproduces
bug)
- ✅ Verified test passes with `bun bd test` (confirms fix)
- ✅ Test covers the exact reproduction case from the issue
- ✅ Additional tests for edge cases (actual listeners, nested calls)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
Fixes#19111
This PR fixes a bug where `fs.createReadStream().pipe(ServerResponse)`
would fail to transfer data when ServerResponse had no handle
(standalone usage). This affected Vite's static file serving and other
middleware adapters using the connect-to-web pattern.
## Root Cause
The bug was in the `ServerResponse.writableNeedDrain` getter at line
1529 of `_http_server.ts`:
```typescript
return !this.destroyed && !this.finished && (this[kHandle]?.bufferedAmount ?? 1) !== 0;
```
When `ServerResponse` had no handle (which is common in middleware
scenarios), the nullish coalescing operator defaulted `bufferedAmount`
to **1** instead of **0**. This caused `writableNeedDrain` to always
return `true`.
## Impact
When `pipe()` checks `dest.writableNeedDrain === true`, it immediately
pauses the source stream to handle backpressure. With the bug,
standalone ServerResponse instances always appeared to need draining,
causing piped streams to pause and never resume.
## Fix
Changed the default value from `1` to `0`:
```typescript
return !this.destroyed && !this.finished && (this[kHandle]?.bufferedAmount ?? 0) !== 0;
```
## Test Plan
- ✅ Added regression test in `test/regression/issue/19111.test.ts`
- ✅ Verified fix with actual Vite middleware reproduction
- ✅ Confirmed behavior matches Node.js
Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
Fixes#23133
This PR fixes a bug where lifecycle hooks (`beforeAll`, `beforeEach`,
`afterAll`, `afterEach`) would throw an error when called with a
function and options object:
```typescript
beforeAll(() => {
console.log("beforeAll")
}, { timeout: 10_000 })
```
Previously, this would throw: `error: beforeAll() expects a function as
the second argument`
## Root Cause
The issue was in `ScopeFunctions.parseArguments()` at
`src/bun.js/test/ScopeFunctions.zig:342`. When parsing two arguments, it
always treated them as `(description, callback)` instead of checking if
they could be `(callback, options)`.
## Solution
Updated the two-argument parsing logic to check if the first argument is
a function and the second is not a function. In that case, treat them as
`(callback, options)` instead of `(description, callback)`.
## Changes
- Modified `src/bun.js/test/ScopeFunctions.zig` to handle `(callback,
options)` case
- Added regression test at `test/regression/issue/23133.test.ts`
## Testing
✅ Verified the fix works with the reproduction case from the issue
✅ Added comprehensive regression test covering all lifecycle hooks with
both object and numeric timeout options
✅ All existing jest-hooks tests still pass
✅ Test fails with `USE_SYSTEM_BUN=1` and passes with the fixed build
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: pfg <pfg@pfg.pw>
## Summary
Fixes `Buffer.isEncoding('')` to return `false` instead of `true`,
matching Node.js behavior.
## Description
Previously, `Buffer.isEncoding('')` incorrectly returned `true` in Bun,
while Node.js correctly returns `false`. This was caused by
`parseEnumerationFromView` in `JSBufferEncodingType.cpp` treating empty
strings (length 0) as valid utf8 encoding.
The fix modifies the switch statement to return `std::nullopt` for empty
strings, along with other invalid short strings.
## Changes
- Modified `src/bun.js/bindings/JSBufferEncodingType.cpp` to return
`std::nullopt` for empty strings
- Added regression test `test/regression/issue23966.test.ts`
## Test Plan
- [x] Test fails with `USE_SYSTEM_BUN=1 bun test
test/regression/issue23966.test.ts` (confirms bug exists)
- [x] Test passes with `bun bd test test/regression/issue23966.test.ts`
(confirms fix works)
- [x] Verified behavior matches Node.js v24.3.0
- [x] All test cases for valid/invalid encodings pass
Fixes#23966🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Fixes#19652
## Summary
Fixes a crash that occurred when using the `--production` flag with `bun
build`, particularly on Windows where assertions are enabled in release
builds.
## Root Cause
The crash occurred because an assertion for `jsx.development` was
running **before** `jsx.development` was properly configured. The
problematic sequence was:
1. Set `NODE_ENV=production` in env map
2. Call `configureDefines()` which reads `NODE_ENV` and calls
`setProduction(true)`, setting `jsx.development=false`
3. ❌ **Assert `jsx.development` is false** (assertion fired here, before
line 203 below)
4. Set `jsx.development = !production` on line 203 (too late)
## Changes
This PR reorders the code to move the assertion **after**
`jsx.development` is properly set:
1. Set both `BUN_ENV` and `NODE_ENV` to `"production"` in env map
2. Call `configureDefines()`
3. Set `jsx.development = !production` (now happens first)
4. ✅ **Assert `jsx.development` is false** (now runs after it's set)
Also adds `BUN_ENV=production` to match the behavior of setting
`NODE_ENV`.
## Test Plan
Added regression test in `test/regression/issue/19652.test.ts` that
verifies `bun build --production` doesn't crash.
The test:
- ✅ Passes on this branch
- ❌ Would fail on main (assertion failure)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
### What does this PR do?
Fixes#23489
The YAML parser was incorrectly treating `...` inside double-quoted
strings as document end markers, causing parse errors for strings
containing ellipsis, particularly affecting internationalized text.
### Example of the bug:
```yaml
balance: "👛 لا تمتلك محفظة... !"
```
This would fail with: `error: Unexpected document end`
### Root cause:
The bug was introduced in commit fcbd57ac48 which attempted to optimize
document marker detection by using `self.line_indent == .none` instead
of tracking newlines with a local flag. However, this check was
incomplete - it didn't track whether we had just processed a newline
character.
### The fix:
Restored the `nl` (newline) flag pattern from the single-quoted scanner
and combined it with the `line_indent` check. Document markers `...` and
`---` are now only recognized when **all** of these conditions are met:
1. We're after a newline (`nl == true`)
2. We're at column 0 (`self.line_indent == .none`)
3. Followed by whitespace or EOF
This allows `...` to appear freely in double-quoted strings while still
correctly recognizing actual document end markers at the start of lines.
### How did you verify your code works?
1. Reproduced the original issue from #23489
2. Applied the fix and verified all test cases pass:
- Original Arabic text with emoji: `"👛 لا تمتلك محفظة... !"`
- Various `...` positions: start, middle, end
- Both single and double quotes
- Multiline strings with indented `...` (issue #22392)
3. Created regression test in `test/regression/issue/23489.test.ts`
4. Verified existing YAML tests still pass (514 pass, up from 513)
cc @dylan-conway for review
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
Fixes#23569
## Summary
HTML imports require bundling to work correctly, as they need to process
and transform linked assets (JS/CSS). When `--no-bundle` is used, no
bundling or transformation happens, which causes a crash.
This change adds validation to detect HTML entrypoints when
`--no-bundle` is used and provides a clear error message explaining that
"HTML imports are only supported when bundling".
## Changes
- Added validation in `src/cli/build_command.zig` to check for HTML
entrypoints when `--no-bundle` flag is used
- Shows clear error message: "HTML imports are only supported when
bundling"
- Added regression tests in `test/regression/issue/23569.test.ts`
## Test Plan
### Before
```bash
$ bun build ./index.html --no-bundle
# Crashes without helpful error
```
### After
```bash
$ bun build ./index.html --no-bundle
error: HTML imports are only supported when bundling
```
### Tests
- ✅ Test with `--no-bundle` flag errors correctly
- ✅ Test with `--no-bundle --outdir` errors correctly
- ✅ Test without `--no-bundle` works normally
- ✅ All 3 regression tests pass
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
### What does this PR do?
Fixes#23621.
Note that the quality of this code is quite low, but since Redis is
getting a rewrite, this is a stop-gap. The tests are what really matters
here.
This whole PR is claude.
### How did you verify your code works?
CI.
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
