ty 0.0.40

on Python PyPI

Release Notes

Released on 2026-05-27.

Bug fixes

• Accept complete enum-literal alias unions as enums (#25341)
• Fix diagnostics in ignored folders after adding new files (#25236)
• Show LiteralString when hovering over an inline of a literal string (#25373)

LSP server

• Follow aliases when resolving stub mappings (#25328)
• Treat Python notebook text documents as Python sources (#25393)
• Recover incomplete list comprehension elements (#25326)

Diagnostics

• Add help message to invalid-generic-class variance diagnostic (#25385)

Core type checking

• Ignore and reject annotations on non-name targets (#25324)
• Infer class attributes assigned by metaclass initialization (#25342)
• Reject inconsistent generic bases in dynamic classes (#25413)
• Resolve enum names for all unions arms in literal enum subsets (#25379)
• Support typing.TypeForm (#25334)
• Use constraint sets as pending state in SpecializationBuilder (#24540)

Contributors

• @anuraaga
• @dcreager
• @charliermarsh
• @MichaReiser
• @Dev-X25874

Install ty 0.0.40

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/ty/releases/download/0.0.40/ty-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/ty/releases/download/0.0.40/ty-installer.ps1 | iex"

Download ty 0.0.40

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo astral-sh/ty

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>