## 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
- Adds `import { feature } from "bun:bundle"` for compile-time feature
flag checking
- `feature("FLAG_NAME")` calls are replaced with `true`/`false` at
bundle time
- Enables dead-code elimination through `--feature=FLAG_NAME` CLI
argument
- Works in `bun build`, `bun run`, and `bun test`
- Available in both CLI and `Bun.build()` JavaScript API
## Usage
```ts
import { feature } from "bun:bundle";
if (feature("SUPER_SECRET")) {
console.log("Secret feature enabled!");
} else {
console.log("Normal mode");
}
```
### CLI
```bash
# Enable feature during build
bun build --feature=SUPER_SECRET index.ts
# Enable at runtime
bun run --feature=SUPER_SECRET index.ts
# Enable in tests
bun test --feature=SUPER_SECRET
```
### JavaScript API
```ts
await Bun.build({
entrypoints: ['./index.ts'],
outdir: './out',
features: ['SUPER_SECRET', 'ANOTHER_FLAG'],
});
```
## Implementation
- Added `bundler_feature_flags` (as `*const bun.StringSet`) to
`RuntimeFeatures` and `BundleOptions`
- Added `bundler_feature_flag_ref` to Parser struct to track the
`feature` import
- Handle `bun:bundle` import at parse time (similar to macros) - capture
ref, return empty statement
- Handle `feature()` calls in `e_call` visitor - replace with boolean
based on flags
- Wire feature flags through CLI arguments and `Bun.build()` API to
bundler options
- Added `features` option to `JSBundler.zig` for JavaScript API support
- Added TypeScript types in `bun.d.ts`
- Added documentation to `docs/bundler/index.mdx`
## Test plan
- [x] Basic feature flag enabled/disabled tests (both CLI and API
backends)
- [x] Multiple feature flags test
- [x] Dead code elimination verification tests
- [x] Error handling for invalid arguments
- [x] Runtime tests with `bun run --feature=FLAG`
- [x] Test runner tests with `bun test --feature=FLAG`
- [x] Aliased import tests (`import { feature as checkFeature }`)
- [x] Ternary operator DCE tests
- [x] Tests use `itBundled` with both `backend: "cli"` and `backend:
"api"`
🤖 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: Alistair Smith <hi@alistair.sh>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
## Summary
Implements `--no-env-file` CLI flag and bunfig configuration options to
disable automatic `.env` file loading at runtime and in the bundler.
## Motivation
Users may want to disable automatic `.env` file loading for:
- Production environments where env vars are managed externally
- CI/CD pipelines where .env files should be ignored
- Testing scenarios where explicit env control is needed
- Security contexts where .env files should not be trusted
## Changes
### CLI Flag
- Added `--no-env-file` flag that disables loading of default .env files
- Still respects explicit `--env-file` arguments for intentional env
loading
### Bunfig Configuration
Added support for disabling .env loading via `bunfig.toml`:
- `env = false` - disables default .env file loading
- `env = null` - disables default .env file loading
- `env.file = false` - disables default .env file loading
- `env.file = null` - disables default .env file loading
### Implementation
- Added `disable_default_env_files` field to `api.TransformOptions` with
serialization support
- Added `disable_default_env_files` field to `options.Env` struct
- Implemented `loadEnvConfig` in bunfig parser to handle env
configuration
- Wired up flag throughout runtime and bundler code paths
- Preserved package.json script runner behavior (always skips default
.env files)
## Tests
Added comprehensive test suite (`test/cli/run/no-envfile.test.ts`) with
9 tests covering:
- `--no-env-file` flag with `.env`, `.env.local`,
`.env.development.local`
- Bunfig configurations: `env = false`, `env.file = false`, `env = true`
- `--no-env-file` with `-e` eval flag
- `--no-env-file` combined with `--env-file` (explicit files still load)
- Production mode behavior
All tests pass with debug bun and fail with system bun (as expected).
## Example Usage
```bash
# Disable all default .env files
bun --no-env-file index.js
# Disable defaults but load explicit file
bun --no-env-file --env-file .env.production index.js
# Disable via bunfig.toml
cat > bunfig.toml << 'CONFIG'
env = false
CONFIG
bun index.js
```
## Files Changed
- `src/cli/Arguments.zig` - CLI flag parsing
- `src/api/schema.zig` - API schema field with encode/decode
- `src/options.zig` - Env struct field and wiring
- `src/bunfig.zig` - Config parsing with loadEnvConfig
- `src/transpiler.zig` - Runtime wiring
- `src/bun.js.zig` - Runtime wiring
- `src/cli/exec_command.zig` - Runtime wiring
- `src/cli/run_command.zig` - Preserved package.json script runner
behavior
- `test/cli/run/no-envfile.test.ts` - Comprehensive test suite
🤖 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?
Adds support for `publicHoistPattern` in `bunfig.toml` and
`public-hoist-pattern` from `.npmrc`. This setting allows you to select
transitive packages to hoist to the root node_modules making them
available for all workspace packages.
```toml
[install]
# can be a string
publicHoistPattern = "@types*"
# or an array
publicHoistPattern = [ "@types*", "*eslint*" ]
```
`publicHoistPattern` only affects the isolated linker.
---
Adds `hoistPattern`. `hoistPattern` is the same as `publicHoistPattern`,
but applies to the `node_modules/.bun/node_modules` directory instead of
the root node_modules. Also the default value of `hoistPattern` is `*`
(everything is hoisted to `node_modules/.bun/node_modules` by default).
---
Fixes a determinism issue constructing the
`node_modules/.bun/node_modules` directory.
---
closes#23481closes#6160closes#23548
### How did you verify your code works?
Added tests for
- [x] only include patterns
- [x] only exclude patterns
- [x] mix of include and exclude
- [x] errors for unexpected expression types
- [x] excluding direct dependency (should still include)
- [x] match all with `*`
- [x] string and array expression types
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
### What does this PR do?
This PR implements support for the `email` field in `.npmrc` files for
registry scope authentication. Some private registries (particularly
Nexus) require the email field to be specified in the registry
configuration alongside username/password or token authentication.
The email field can now be specified in `.npmrc` files like:
```ini
//registry.example.com/:email=user@example.com
//registry.example.com/:username=myuser
//registry.example.com/:_password=base64encodedpassword
```
### How did you verify your code works?
1. **Built Bun successfully** - Confirmed the code compiles without
errors using `bun bd --debug`
2. **Wrote comprehensive unit tests** - Added two test cases to
`test/cli/install/npmrc.test.ts`:
- Test for standalone email field parsing
- Test for email combined with username/password authentication
3. **Verified tests pass** - Ran `bun bd test
test/cli/install/npmrc.test.ts -t "email"` and confirmed both tests
pass:
```
✓ 2 pass
✓ 0 fail
✓ 6 expect() calls
```
4. **Code changes include**:
- Added `email` field to `NpmRegistry` struct in `src/api/schema.zig`
- Updated `encode()` and `decode()` methods to handle the email field
- Modified `ini.zig` to parse and store the email field from `.npmrc`
- Removed email from the unsupported options warning (certfile and
keyfile remain unsupported)
- Updated all `NpmRegistry` struct initializations to include the email
field
- Updated `loadNpmrcFromJS` test API to return the email field
🤖 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?
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
### What does this PR do?
fixes#22679
* includes a better error if a package cant be met because of the age
(but would normally)
* logs the resolved one in --verbose (which can be helpful in debugging
to show it does know latest but couldn't use)
* makes bun outdated show in the table when the package isn't true
latest
* includes a rudimentary "stability" check if a later version is in
blacked out time (but only up to 7 days as it goes back to latest with
min age)
For extended security we could also Last-Modified header of the tgz
download and then abort if too new (just like the hash)
| install error with no recent version | bun outdated respecting the
rule |
| --- | --- |
<img width="838" height="119" alt="image"
src="https://github.com/user-attachments/assets/b60916a8-27f6-4405-bfb6-57f9fa8bb0d6"
/> | <img width="609" height="314" alt="image"
src="https://github.com/user-attachments/assets/d8869ff4-8e16-492c-8e4c-9ac1dfa302ba"
/> |
For stable release we will make it use `3d` type syntax instead of magic
second numbers.
### How did you verify your code works?
tests & manual
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
## Summary
Implements the `jsxSideEffects` option to control whether JSX elements
are marked as pure for dead code elimination, matching esbuild's
behavior from their TestJSXSideEffects test case.
## Features Added
- **tsconfig.json support**: `{"compilerOptions": {"jsxSideEffects":
true}}`
- **CLI flag support**: `--jsx-side-effects`
- **Dual runtime support**: Works with both classic
(`React.createElement`) and automatic (`jsx`/`jsxs`) JSX runtimes
- **Production/Development modes**: Works in both production and
development environments
- **Backward compatible**: Default value is `false` (maintains existing
behavior)
## Behavior
- **Default (`jsxSideEffects: false`)**: JSX elements marked with `/*
@__PURE__ */` comments (can be eliminated by bundlers)
- **When `jsxSideEffects: true`**: JSX elements NOT marked as pure
(always preserved)
## Example Usage
### tsconfig.json
```json
{
"compilerOptions": {
"jsxSideEffects": true
}
}
```
### CLI
```bash
bun build --jsx-side-effects
```
### Output Comparison
```javascript
// Input: console.log(<div>test</div>);
// Default (jsxSideEffects: false):
console.log(/* @__PURE__ */ React.createElement("div", null, "test"));
// With jsxSideEffects: true:
console.log(React.createElement("div", null, "test"));
```
## Implementation Details
- Added `side_effects: bool = false` field to `JSX.Pragma` struct
- Updated tsconfig.json parser to handle `jsxSideEffects` option
- Added CLI argument parsing for `--jsx-side-effects` flag
- Modified JSX element visiting logic to respect the `side_effects`
setting
- Updated API schema with proper encode/decode support
- Enhanced test framework to support the new JSX option
## Comprehensive Test Coverage (12 Tests)
### Core Functionality (4 tests)
- ✅ Classic JSX runtime with default behavior (includes `/* @__PURE__
*/`)
- ✅ Classic JSX runtime with `side_effects: true` (no `/* @__PURE__ */`)
- ✅ Automatic JSX runtime with default behavior (includes `/* @__PURE__
*/`)
- ✅ Automatic JSX runtime with `side_effects: true` (no `/* @__PURE__
*/`)
### Production Mode (4 tests)
- ✅ Classic JSX runtime in production with default behavior
- ✅ Classic JSX runtime in production with `side_effects: true`
- ✅ Automatic JSX runtime in production with default behavior
- ✅ Automatic JSX runtime in production with `side_effects: true`
### tsconfig.json Integration (4 tests)
- ✅ Default tsconfig.json behavior (automatic runtime, includes `/*
@__PURE__ */`)
- ✅ tsconfig.json with `jsxSideEffects: true` (automatic runtime, no `/*
@__PURE__ */`)
- ✅ tsconfig.json with `jsx: "react"` and `jsxSideEffects: true`
(classic runtime)
- ✅ tsconfig.json with `jsx: "react-jsx"` and `jsxSideEffects: true`
(automatic runtime)
### Snapshot Testing
All tests include inline snapshots demonstrating the exact output
differences, providing clear documentation of the expected behavior.
### Existing Compatibility
- ✅ All existing JSX tests continue to pass
- ✅ Cross-platform Zig compilation succeeds
## Closes
Fixes#22295🤖 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>
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>
### What does this PR do?
Fixes#22014
todo:
- [x] not spawn sync
- [x] better comm to subprocess (not stderr)
- [x] tty
- [x] more tests (also include some tests for the actual implementation
of a provider)
- [x] disable autoinstall?
Scanner template: https://github.com/oven-sh/security-scanner-template
<!-- **Please explain what your changes do**, example: -->
<!--
This adds a new flag --bail to bun test. When set, it will stop running
tests after the first failure. This is useful for CI environments where
you want to fail fast.
-->
---
- [x] Documentation or TypeScript types (it's okay to leave the rest
blank in this case)
- [x] Code changes
### How did you verify your code works?
<!-- **For code changes, please include automated tests**. Feel free to
uncomment the line below -->
<!-- I wrote automated tests -->
<!-- If JavaScript/TypeScript modules or builtins changed:
- [ ] I included a test for the new code, or existing tests cover it
- [ ] I ran my tests locally and they pass (`bun-debug test
test-file-name.test`)
-->
<!-- If Zig files changed:
- [ ] I checked the lifetime of memory allocated to verify it's (1)
freed and (2) only freed when it should be
- [ ] I included a test for the new code, or an existing test covers it
- [ ] JSValue used outside of the stack is either wrapped in a
JSC.Strong or is JSValueProtect'ed
- [ ] I wrote TypeScript/JavaScript tests and they pass locally
(`bun-debug test test-file-name.test`)
-->
<!-- If new methods, getters, or setters were added to a publicly
exposed class:
- [ ] I added TypeScript types for the new methods, getters, or setters
-->
<!-- If dependencies in tests changed:
- [ ] I made sure that specific versions of dependencies are used
instead of ranged or tagged versions
-->
<!-- If a new builtin ESM/CJS module was added:
- [ ] I updated Aliases in `module_loader.zig` to include the new module
- [ ] I added a test that imports the module
- [ ] I added a test that require() the module
-->
tests (bad currently)
---------
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Dylan Conway <dylan-conway@users.noreply.github.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
