### What does this PR do?
When Error.captureStackTrace(e, fn) is called with a function that isn't
in the call stack, all frames are filtered out and e.stack should return
just the error name and message (e.g. "Error: test"), matching Node.js
behavior. Previously Bun returned undefined because:
1. The empty frame vector replaced the original stack frames via
setStackFrames(), but the lazy stack accessor was only installed when
hasMaterializedErrorInfo() was true (i.e. stack was previously
accessed). When it wasn't, JSC's internal materialization saw the
empty/null frames and produced no stack property at all.
2. The custom lazy getter returned undefined when stackTrace was
nullptr, instead of computing the error name+message string with zero
frames.
Fix: always force materialization before replacing frames, always
install the custom lazy accessor, and handle nullptr stackTrace in the
getter by computing the error string with an empty frame list.
### How did you verify your code works?
---------
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?
Updates WebKit to
5b6a0ac49b
### How did you verify your code works?
---------
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: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
- WTFMove → WTF::move / std::move: Replaced WTFMove() macro with
WTF::move() function for WTF types, std::move() for std types
- SortedArrayMap removed: Replaced with if-else chains in
EventFactory.cpp, JSCryptoKeyUsage.cpp
- Wasm::Memory::create signature changed: Removed VM parameter
- URLPattern allocation: Changed from WTF_MAKE_ISO_ALLOCATED to
WTF_MAKE_TZONE_ALLOCATED
---------
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
## Summary
Implements the `--cpu-prof` CLI flag for Bun to profile CPU usage and
save results in Chrome CPU Profiler JSON format, compatible with Chrome
DevTools and VSCode.
## Implementation Details
- Uses JSC's `SamplingProfiler` to collect CPU samples during execution
- Converts samples to Chrome CPU Profiler JSON format on exit
- Supports `--cpu-prof-name` to customize output filename
- Supports `--cpu-prof-dir` to specify output directory
- Default filename: `CPU.YYYYMMDD.HHMMSS.PID.0.001.cpuprofile`
## Key Features
✅ **Chrome DevTools Compatible** - 100% compatible with Node.js CPU
profile format
✅ **Absolute Timestamps** - Uses wall clock time (microseconds since
epoch)
✅ **1ms Sampling** - Matches Node.js sampling frequency for comparable
granularity
✅ **Thread-Safe** - Properly shuts down background sampling thread
before processing
✅ **Memory-Safe** - Uses HeapIterationScope and DeferGC for safe heap
access
✅ **Cross-Platform** - Compiles on Windows, macOS, and Linux with proper
path handling
## Technical Challenges Solved
1. **Heap Corruption** - Fixed by calling `profiler->shutdown()` before
processing traces
2. **Memory Safety** - Added `HeapIterationScope` and `DeferGC` when
accessing JSCells
3. **Timestamp Accuracy** - Explicitly start stopwatch and convert to
absolute wall clock time
4. **Path Handling** - Used `bun.path.joinAbsStringBufZ` with proper cwd
resolution
5. **Windows Support** - UTF-16 path conversion for Windows
compatibility
6. **Atomic Writes** - Used `bun.sys.File.writeFile` with ENOENT retry
## Testing
All tests pass (4/4):
- ✅ Generates profile with default name
- ✅ `--cpu-prof-name` sets custom filename
- ✅ `--cpu-prof-dir` sets custom directory
- ✅ Profile captures function names
Verified format compatibility:
- JSON structure matches Node.js exactly
- All samples reference valid nodes
- Timestamps use absolute microseconds since epoch
- Cross-platform compilation verified with `bun run zig:check-all`
## Example Usage
```bash
# Basic usage
bun --cpu-prof script.js
# Custom filename
bun --cpu-prof --cpu-prof-name my-profile.cpuprofile script.js
# Custom directory
bun --cpu-prof --cpu-prof-dir ./profiles script.js
```
Output can be opened in Chrome DevTools (Performance → Load Profile) or
VSCode's CPU profiling viewer.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude <noreply@anthropic.com>
