Bump ruff from 0.15.21 to 0.16.4 in the dev-dependencies group across 1 directory

[dependabot]

Bumps the dev-dependencies group with 1 update in the / directory: ruff.

Updates ruff from 0.15.21 to 0.16.4

Release notes

Sourced from ruff's releases.

0.16.4

Release Notes

Released on 2026-08-20.

Preview features

• [flake8-use-pathlib] Add autofix for PTH116 (#26460)
• [refurb] Restrict delete-full-slice to lists (FURB131) (#27711)
• [refurb] Skip FURB101 and FURB103 when the open argument is a file descriptor (#27643)

Bug fixes

• Fix InvalidInstruction on Windows CPUs that do not support POPCNT (#27803)
• [pyflakes] Emit semantic syntax errors in string type definitions as F722 (#27835)
• [pylint] Allow os._exit imports in import-private-name (PLC2701) (#27738)

Rule changes

• [syntax-errors] Align mixed t-string/bytes error message with CPython 3.14 (#27766)
• [ruff] Add ctypes.LittleEndianStructure and related types to existing exception (RUF012) (#27753)
• [syntax-errors] Detect duplicate keyword arguments (#17804)
• [syntax-errors] Detect parameters declared nonlocal (#27628)

Server

• Offer display-only fixes and mark safe fixes preferred (#27807)
• Support pull diagnostics for notebook cells (#27779)

Documentation

• Add default indicator to rules table (#27724)
• Fix broken link to Python docs (#27757)

Other changes

• Fix s390x stacker assembly in release builds (#27776)
• Guarantee minimum stack size when parsing a module, standalone expression, and suites (#25464)
• Reduce configuration deserialization code size (#27924)
• Check packed AST index bounds (#27849)

Contributors

• @​AbhinavMir
• @​eduardorittner
• @​royb3
• @​MichaReiser
• @​carljm
• @​rosstitmarsh
• @​ntBre

... (truncated)

Changelog

Sourced from ruff's changelog.

0.16.4

Released on 2026-08-20.

Preview features

• [flake8-use-pathlib] Add autofix for PTH116 (#26460)
• [refurb] Restrict delete-full-slice to lists (FURB131) (#27711)
• [refurb] Skip FURB101 and FURB103 when the open argument is a file descriptor (#27643)

Bug fixes

• Fix InvalidInstruction on Windows CPUs that do not support POPCNT (#27803)
• [pyflakes] Emit semantic syntax errors in string type definitions as F722 (#27835)
• [pylint] Allow os._exit imports in import-private-name (PLC2701) (#27738)

Rule changes

• [syntax-errors] Align mixed t-string/bytes error message with CPython 3.14 (#27766)
• [ruff] Add ctypes.LittleEndianStructure and related types to existing exception (RUF012) (#27753)
• [syntax-errors] Detect duplicate keyword arguments (#17804)
• [syntax-errors] Detect parameters declared nonlocal (#27628)

Server

• Offer display-only fixes and mark safe fixes preferred (#27807)
• Support pull diagnostics for notebook cells (#27779)

Documentation

• Add default indicator to rules table (#27724)
• Fix broken link to Python docs (#27757)

Other changes

• Fix s390x stacker assembly in release builds (#27776)
• Guarantee minimum stack size when parsing a module, standalone expression, and suites (#25464)
• Reduce configuration deserialization code size (#27924)
• Check packed AST index bounds (#27849)

Contributors

• @​AbhinavMir
• @​eduardorittner
• @​royb3
• @​MichaReiser
• @​carljm
• @​rosstitmarsh
• @​ntBre
• @​zaniebot

... (truncated)

Commits

• 11c76bf Bump 0.16.4 (#27937)
• d53c8c5 Isolate playground builds from deployment credentials (#27839)
• cab001e Disable uv preview for releases and pre-commit hooks (#27939)
• f8d575f [ty] Clarify writing guidance for human readers (#27912)
• ca45fae Set --preview and --default-index for the uv-lock hook (#27935)
• 4827bf7 Export UV_DEFAULT_INDEX in release.sh (#27934)
• d1087a4 [ty] Handle assignment expressions in string annotations (#27921)
• 680cce4 [ty] Optimize inherited recursive protocol comparisons (#27922)
• 974d3cb Upgrade ecosystem-analyzer and mypy_primer to the latest upstream pins (#27932)
• b169b40 Install cargo tools locked (#27929)
• Additional commits viewable in compare view

Note
Automatic rebases have been disabled on this pull request as it has been open for over 30 days.

[cursor]

Incomplete ruff 0.16 migration

High Severity

Bumping ruff to 0.16.0 without updating lint config adopts 413 default rules (up from 59). ruff.toml and pyproject.toml set no lint.select, and Trunk runs bare ruff check, so CI will surface many new violations and can fail without any code changes.

 

^{Reviewed by Cursor Bugbot for commit 572330f. Configure here.}

[cursor]

Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

There are 2 total unresolved issues (including 1 from previous review).

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

Want higher recall? High effort reviews run extra passes and find more bugs. A team admin can switch effort levels in the Cursor dashboard.

^{Reviewed by Cursor Bugbot for commit 859de5d. Configure here.}

[cursor]

Lockfile left on old ruff

Medium Severity

pyproject.toml pins ruff==0.16.2, but uv.lock still resolves and records ruff==0.15.21. Lint CI runs uv sync --frozen, so it keeps installing 0.15.21 and never exercises the declared bump, while non-frozen installs diverge from CI.

 

^{Reviewed by Cursor Bugbot for commit 859de5d. Configure here.}