Pyrefly v0.27.0

Status: ALPHA

Release date: 2025-08-04

Pyrefly 0.27.0 bundles 212 commits from 20 contributors

📝 Changelog

Typechecking

• Caught exception names are now correctly out of scope after except clauses.
• Variables declared with only annotations (e.g., x: int) are no longer always assumed uninitialized.
• Assignments to inherited attributes within method bodies are no longer treated as re-declarations.
• Prevented crashes from overlapping UsageLink ranges by using YieldLink for yield calculations.
• Corrected the type for __path__ to MutableSequence.

IDE

• Overloads are now supported on completion and metaclass/__new__/__init__ calls are treated as overloads.
• cls arguments are removed from completion and signature help.
• VSCode extension name issue resolved by using displayName in package.json.
• Docstring indentation trimming now ignores the first line.
• More concise display for top-level types
• Function arguments in hover types are formatted on new lines if there's more than one.

Misc.

• Fix crash when receiving non-file change events.

📦 Upgrade

pip install --upgrade pyrefly==0.27.0

🖊️ Contributors this release

@stroxler @fangyi-zhou @rubmary @kinto0 @grievejia @rchen152 @ndmitchell @aahanaggarwal @javabster @connernilsen @migeed-z @SamChou19815 @yangdanny97

Full Changelog: https://github.com/facebook/pyrefly/compare/0.26.0..0.27.0