…int.generate()
`ServerEntryPoint.source` defaults to `undefined`, and accessing its
`.contents` or `.path.text` fields before `generate()` has been called
causes a segfault. This happens when `bun:main` is resolved in contexts
where `entry_point.generate()` is skipped (HTML entry points) or never
called (test runner).
Add a `generated` flag to `ServerEntryPoint` and guard both access
sites:
- `getHardcodedModule()` in ModuleLoader.zig (returns null instead of
crashing)
- `_resolve()` in VirtualMachine.zig (falls through to normal
resolution)
### What does this PR do?
### How did you verify your code works?
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
- Implement complete lowering of TC39 stage-3 standard ES decorators
(the non-legacy variant used when tsconfig has no
`experimentalDecorators`).
- Passes all 147 esbuild decorator tests and 22 additional Bun-specific
tests (191 total, 0 failures).
- Supports method, getter, setter, field, auto-accessor, private member,
and class decorators in both statement and expression positions, with
proper evaluation order, class binding semantics, and decorator
metadata.
Fixes#4122Fixes#20206Fixes#14529Fixes#6051
## What's implemented
| Feature | Details |
|---|---|
| Method/getter/setter decorators | Static and instance, public and
private |
| Field decorators | Initializer replacement + extra initializers via
`__runInitializers` |
| Auto-accessor (`accessor` keyword) | Lowered to WeakMap storage +
getter/setter pair |
| Private member decorators | WeakMap/WeakSet lowering with
`__privateGet`/`__privateSet` |
| Class decorators | Statement and expression positions |
| Class expression decorators | Comma-expression lowering (no IIFE) |
| Decorator metadata | `Symbol.metadata` support via
`__decoratorMetadata` |
| Evaluation order | All decorator expressions + computed keys evaluated
in source order per TC39 spec |
| Class binding semantics | Separate inner/outer class name bindings
(element vs class decorator closures) |
| Static block extraction | `this` replaced with class name ref when
moved to suffix |
| Computed property keys | Pre-evaluated into temp variables for correct
ordering |
## Runtime helpers
Added to `src/runtime.js` and registered in `src/runtime.zig`:
- `__decoratorStart(base)` — creates decorator context array
- `__decorateElement(array, flags, name, decorators, target, extra)` —
applies decorators to a class element
- `__decoratorMetadata(array, target)` — sets `Symbol.metadata` on the
class
- `__runInitializers(array, flags, self, value)` — runs
initializer/extra-initializer arrays
## Test plan
- [x] `bun bd test
test/bundler/transpiler/es-decorators-esbuild.test.ts` — **147/147
pass** (esbuild's full decorator test suite)
- [x] `bun bd test test/bundler/transpiler/es-decorators.test.ts` —
**22/22 pass**
- [x] `bun bd test test/bundler/transpiler/decorators.test.ts` — **22/22
pass** (legacy decorators still work)
- [x] E2E runtime verification of method, field, accessor, class,
private, and expression decorators
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
### What does this PR do?
### How did you verify your code works?
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: claude[bot] <209825114+claude[bot]@users.noreply.github.com>
## Summary
- Adds `Bun.JSON5.parse()` and `Bun.JSON5.stringify()` as built-in APIs
- Adds `.json5` file support in the module resolver and bundler
- Parser uses a scanner/parser split architecture with a labeled switch
pattern (like the YAML parser) — the scanner produces typed tokens, the
parser never touches source bytes directly
- 430+ tests covering the official JSON5 test suite, escape sequences,
numbers, comments, whitespace (including all Unicode whitespace types),
unquoted/reserved-word keys, unicode identifiers, deeply nested
structures, garbage input, error messages, and stringify behavior
<img width="659" height="610" alt="Screenshot 2026-01-25 at 12 19 57 AM"
src="https://github.com/user-attachments/assets/e300125a-f197-4cad-90ed-e867b6232a01"
/>
## Test plan
- [x] `bun bd test test/js/bun/json5/json5.test.ts` — 317 tests
- [x] `bun bd test test/js/bun/json5/json5-test-suite.test.ts` — 113
tests from the official JSON5 test suite
- [x] `bun bd test test/js/bun/resolve/json5/json5.test.js` — .json5
module resolution
closes#3175🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
Fixes native module export corruption when compiling multiple NAPI
modules with `bun build --compile` on Linux.
- When loading multiple `.node` files in a compiled binary, the second
module would incorrectly get the first module's exports
- Root cause: memfd file descriptors were closed after dlopen, allowing
fd reuse. Since dlopen caches by path (`/proc/self/fd/N`), it returned
the wrong cached handle
- This bug occurs when loading native modules in quick succession, as
the fd number is likely to be reused immediately after being closed
- Fix: Disable the memfd optimization and always use temp files with
unique paths
## Test plan
- [x] Added regression test in `test/regression/issue/26045/`
- [x] Test fails with production bun (v1.3.6)
- [x] Test passes with the fix
Fixes https://github.com/oven-sh/bun/issues/26045🤖 Generated with [Claude Code](https://claude.com/claude-code)
## Summary
- Aligns Bun's temp directory resolution with Node.js's `os.tmpdir()`
behavior
- Checks `TMPDIR`, `TMP`, and `TEMP` environment variables in order
(matching Node.js)
- Uses `bun.once` for lazy initialization instead of mutable static
state
- Removes `setTempdir` function and simplifies the API to use
`RealFS.tmpdirPath()` directly
## Test plan
- [ ] Verify temp directory resolution matches Node.js behavior
- [ ] Test with various environment variable configurations
- [ ] Ensure existing tests pass with `bun bd test`
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude <noreply@anthropic.com>
## Summary
- Add `MemfdFlags` enum to replace raw integer flags for `memfd_create`,
providing semantic clarity for different use cases (`executable`,
`non_executable`, `cross_process`)
- Add support for `MFD_EXEC` and `MFD_NOEXEC_SEAL` flags (Linux 6.3+)
with automatic fallback to older kernel flags when `EINVAL` is returned
- Use memfd + `/proc/self/fd/{fd}` path for loading embedded `.node`
files in standalone builds, avoiding disk writes entirely on Linux
## Test plan
- [ ] Verify standalone builds with embedded `.node` files work on Linux
- [ ] Verify fallback works on older kernels (pre-6.3)
- [ ] Verify subprocess stdio memfd still works correctly
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude <noreply@anthropic.com>
### What does this PR do?
Makes isolated installs the default install strategy for projects with
workspaces in Bun v1.3.
Also fixes creating patches with `bun patch` and `--linker isolated`
Fixes#22693
### How did you verify your code works?
Added tests for node_modules renaming `bun patch` with isolated install.
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
### What does this PR do?
Three things:
- JSCommonJSExtensions.cpp `onAssign` was returning out of sync numbers
instead of `BunLoaderTypeJS`/`BunLoaderTypeNAPI`/...
- `bun.schema.api.Loader._none` was 255 instead of 254 like
`BunLoaderTypeNone`
- `Bun__transpileFile` used `bun.options.Loader.Optional` instead of
`bun.schema.api.Loader`. `bun.options.Loader` does not have a type kept
in sync in C++.
### How did you verify your code works?
Added tests that make sure the correct loader is used for modules
required with custom _extensions functions
Add `jsc.DecodedJSValue`, an extern struct which is ABI-compatible with
`JSC::JSValue`. (By contrast, `jsc.JSValue` is ABI-compatible with
`JSC::EncodedJSValue`.) This enables `jsc.Strong.get` to be more
efficient: it no longer has to call into C++.
(For internal tracking: fixes ENG-20748)
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
Fixes a crash related to the dev server overwriting the uws user context
pointer when setting abort callback.
Adds support for `return new Response(<jsx />, { ... })` and `return
Response.render(...)` and `return Response.redirect(...)`:
- Created a `SSRResponse` class to handle this (see
`JSBakeResponse.{h,cpp}`)
- `SSRResponse` is designed to "fake" being a React component
- This is done in JSBakeResponse::create inside of
src/bun.js/bindings/JSBakeResponse.cpp
- And `src/js/builtins/BakeSSRResponse.ts` defines a `wrapComponent`
function which wraps
the passed in component (when doing `new Response(<jsx />, ...)`). It
does
this to throw an error (in redirect()/render() case) or return the
component.
- Created a `BakeAdditionsToGlobal` struct which contains some
properties
needed for this
- Added some of the properties we need to fake to BunBuiltinNames.h
(e.g.
`$$typeof`), the rationale behind this is that we couldn't use
`structure->addPropertyTransition` because JSBakeResponse is not a final
JSObject.
- When bake and server-side, bundler rewrites `Response ->
Bun.SSRResponse` (see `src/ast/P.zig` and `src/ast/visitExpr.zig`)
- Created a new WebCore body variant (`Render: struct { path: []const u8
}`)
- Created when `return Response.render(...)`
- When handled, it re-invokes dev server to render the new path
Enables server-side sourcemaps for the dev server:
- New source providers for server-side:
(`DevServerSourceProvider.{h,cpp}`)
- IncrementalGraph and SourceMapStore are updated to support this
There are numerous other stuff:
- allow `app` configuration from Bun.serve(...)
- fix errors stopping dev server
- fix use after free related to in
RequestContext.finishRunningErrorHandler
- Request.cookies
- Make `"use client";` components work
- Fix some bugs using `require(...)` in dev server
- Fix catch-all routes not working in the dev server
- Updates `findSourceMappingURL(...)` to use `std.mem.lastIndexOf(...)`
because
the sourcemap that should be used is the last one anyway
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Alistair Smith <hi@alistair.sh>
## Summary
Fixes#12548 - TypeScript syntax doesn't work in BunPlugin when using
`loader: 'ts'`
## The Problem
When creating a virtual module with `build.module()` and specifying
`loader: 'ts'`, TypeScript syntax like `import { type TSchema }` would
fail to parse with errors like:
```
error: Expected "}" but found "TSchema"
error: Expected "from" but found "}"
```
The same code worked fine when using `loader: 'tsx'`, indicating the
TypeScript parser wasn't being configured correctly for `.ts` files.
## Root Cause
The bug was caused by an enum value mismatch between C++ and Zig:
### Before (Incorrect)
- **C++ (`headers-handwritten.h`)**: `jsx=0, js=1, ts=2, tsx=3, ...`
- **Zig API (`api/schema.zig`)**: `jsx=1, js=2, ts=3, tsx=4, ...`
- **Zig Internal (`options.zig`)**: `jsx=0, js=1, ts=2, tsx=3, ...`
When a plugin returned `loader: 'ts'`, the C++ code correctly parsed the
string "ts" and set `BunLoaderTypeTS=2`. However, when this value was
passed to Zig's `Bun__transpileVirtualModule` function (which expects
`api.Loader`), the value `2` was interpreted as `api.Loader.js` instead
of `api.Loader.ts`, causing the TypeScript parser to not be enabled.
### Design Context
The codebase has two loader enum systems by design:
- **`api.Loader`**: External API interface used for C++/Zig
communication
- **`options.Loader`**: Internal representation used within Zig
The conversion between them happens via `options.Loader.fromAPI()` and
`.toAPI()` functions. The C++ layer should use `api.Loader` values since
that's what the interface functions expect.
## The Fix
1. **Aligned enum values**: Updated the `BunLoaderType` constants in
`headers-handwritten.h` to match the values in `api/schema.zig`,
ensuring C++ and Zig agree on the enum values
2. **Removed unnecessary assertion**: Removed the assertion that
`plugin_runner` must be non-null for virtual modules, as it's not
actually required for modules created via `build.module()`
3. **Added regression test**: Created comprehensive test in
`test/regression/issue/12548.test.ts` that verifies TypeScript syntax
works correctly with the `'ts'` loader
## Testing
### New Tests Pass
- ✅ `test/regression/issue/12548.test.ts` - 2 tests verifying TypeScript
type imports work with `'ts'` loader
### Existing Tests Still Pass
- ✅ `test/js/bun/plugin/plugins.test.ts` - 28 pass
- ✅ `test/bundler/bundler_plugin.test.ts` - 52 pass
- ✅ `test/bundler/bundler_loader.test.ts` - 27 pass
- ✅ `test/bundler/esbuild/loader.test.ts` - 10 pass
- ✅ `test/bundler/bundler_plugin_chain.test.ts` - 13 pass
### Manual Verification
```javascript
// This now works correctly with loader: 'ts'
Bun.plugin({
setup(build) {
build.module('hi', () => ({
contents: "import { type TSchema } from '@sinclair/typebox'",
loader: 'ts', // ✅ Works now (previously failed)
}))
},
})
```
🤖 Generated with [Claude Code](https://claude.ai/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>
Replace `catch bun.outOfMemory()`, which can accidentally catch
non-OOM-related errors, with either `bun.handleOom` or a manual `catch
|err| switch (err)`.
(For internal tracking: fixes STAB-1070)
---------
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
### What does this PR do?
This PR adds builtin YAML parsing with `Bun.YAML.parse`
```js
import { YAML } from "bun";
const items = YAML.parse("- item1");
console.log(items); // [ "item1" ]
```
Also YAML imports work just like JSON and TOML imports
```js
import pkg from "./package.yaml"
console.log({ pkg }); // { pkg: { name: "pkg", version: "1.1.1" } }
```
### How did you verify your code works?
Added some tests for YAML imports and parsed values.
---------
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>
