## Summary
Fixes a crash in `napi_is_exception_pending` that occurs during
environment cleanup when finalizers call this function.
The crash manifested as:
```
panic: Aborted
- napi.h:192: napi_is_exception_pending
- napi.h:516: wrap_cleanup
- napi.h:273: napi_env__::cleanup
```
## Root Cause
Bun's implementation was using `DECLARE_THROW_SCOPE` during cleanup when
JavaScript execution is not safe, and didn't follow Node.js's approach
of avoiding `NAPI_PREAMBLE` for this function.
## Changes Made
1. **Remove `NAPI_PREAMBLE_NO_THROW_SCOPE`** - Node.js explicitly states
this function "must execute when there is a pending exception"
2. **Use `DECLARE_CATCH_SCOPE`** instead of `DECLARE_THROW_SCOPE` for
safety during cleanup
3. **Add safety check** `!env->isFinishingFinalizers()` before accessing
VM
4. **Add `napi_clear_last_error` function** to match Node.js
implementation
5. **Use `napi_clear_last_error`** instead of `napi_set_last_error` for
consistent behavior
## Test Plan
Created comprehensive test that:
- ✅ **Reproduces the original crash scenario** (finalizers calling
`napi_is_exception_pending`)
- ✅ **Verifies it no longer crashes in Bun**
- ✅ **Confirms behavior matches Node.js exactly**
### Test Results
**Before fix:** Would crash with `panic: Aborted` during cleanup
**After fix:**
```
Testing napi_is_exception_pending behavior...
1. Testing basic napi_is_exception_pending:
Status: 0 (should be 0 for napi_ok)
Result: false (should be false - no exception pending)
2. Testing with pending exception:
Exception was thrown as expected: Test exception
3. Testing finalizer scenario (the crash case):
Creating object with finalizer that calls napi_is_exception_pending...
Objects created. Forcing garbage collection...
Garbage collection completed.
napi_is_exception_pending in finalizer: status=0, result=false
[...5 finalizers ran successfully...]
SUCCESS: napi_is_exception_pending works correctly in all scenarios!
```
**Node.js comparison:** Identical output and behavior confirmed.
## Impact
- **Fixes crashes** in native addons that call
`napi_is_exception_pending` in finalizers
- **Improves Node.js compatibility** by aligning implementation approach
- **No breaking changes** - only fixes crash scenario, normal usage
unchanged
The fix aligns Bun's NAPI implementation with Node.js's proven approach
for safe exception checking during environment cleanup.
🤖 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>
