react

Allow setState after await in effects

The React compiler now correctly allows calling setState after an await in effect functions, since code after await runs asynchronously in a microtask rather than synchronously cascading renders. The fix uses dataflow analysis to detect when setState is provably post-await, while still flagging setState before the first await or after conditional awaits as errors.

Fix object property shorthand detection

Fixed a bug where computed object properties were incorrectly marked as shorthand, causing incorrect code generation in the React compiler. The fix ensures that only non-computed properties can be marked as shorthand by adding an explicit check for the property kind before determining shorthand status.

Preserve special character in text

Fixed an issue where React Flight was incorrectly dropping a special Unicode character (U+FEFF) from the beginning of text strings. The text decoder now preserves this character instead of treating it as an encoding signature. New tests verify the fix works with various text sizes and chunk patterns.

Stop compiling functions with arguments

The React Compiler now rejects code that uses the implicit `arguments` object, which was previously causing incorrect memoization and broken rerenders. Instead of trying to support it fully, the compiler now gives users a clear error directing them to use rest parameters (like `...args`) instead.

Add server object references support

Introduced an experimental feature (`enableFlightObjectReferences`) that extends Server References to support objects in addition to functions. Frameworks can now register server-scoped objects (like request parameters) using `registerServerObjectReference`, allowing them to be passed by reference without encoding them in the request body, improving response cacheability.