## Summary
This PR fixes incorrect WriteBarrier initialization patterns throughout
the Bun codebase where `.set()` or `.setEarlyValue()` was being called
in the constructor body or in `finishCreation()`. According to
JavaScriptCore's `WriteBarrier.h`, WriteBarriers that are initialized
during construction should use the `WriteBarrierEarlyInit` constructor
in the initializer list to avoid triggering unnecessary write barriers.
## Changes
The following classes were updated to properly initialize WriteBarrier
fields:
1. **InternalModuleRegistry** - Initialize internal fields in
constructor using `setWithoutWriteBarrier()` instead of calling `.set()`
in `finishCreation()`
2. **AsyncContextFrame** - Pass callback and context to constructor and
use `WriteBarrierEarlyInit`
3. **JSCommonJSModule** - Pass id, filename, dirname to constructor and
use `WriteBarrierEarlyInit`
4. **JSMockImplementation** - Pass initial values to constructor and use
`WriteBarrierEarlyInit`
5. **JSConnectionsList** - Pass connection sets to constructor and use
`WriteBarrierEarlyInit`
6. **JSBunRequest** - Pass params to constructor and initialize both
`m_params` and `m_cookies` using `WriteBarrierEarlyInit`
7. **JSNodeHTTPServerSocket** - Initialize `currentResponseObject` using
`WriteBarrierEarlyInit` instead of calling `setEarlyValue()`
## Why This Matters
From JavaScriptCore's `WriteBarrier.h`:
```cpp
enum WriteBarrierEarlyInitTag { WriteBarrierEarlyInit };
// Constructor for early initialization during object construction
WriteBarrier(T* value, WriteBarrierEarlyInitTag)
{
this->setWithoutWriteBarrier(value);
}
```
Using `WriteBarrierEarlyInit` during construction:
- Avoids triggering write barriers when they're not needed
- Is the correct pattern for initializing WriteBarriers before the
object is fully constructed
- Aligns with JavaScriptCore best practices
## Testing
- ✅ Full debug build completes successfully
- ✅ Basic functionality tested (CommonJS modules, HTTP requests, Node
HTTP servers)
- ✅ No regressions observed
## Note on generate-classes.ts
The code generator (`generate-classes.ts`) does not need updates because
generated classes intentionally leave WriteBarrier fields (callbacks,
cached fields, values) uninitialized. They start with
default-constructed WriteBarriers and are populated later by Zig code
via setter functions, which is the correct pattern for those fields.
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
8197a5f7af
