Rule S101 [1] is not in the default settings. If you choose to enable it, you have the possibility of disabling it for your tests like so: [tool.ruff.lint.

Rule S101 [1] is not in the default settings. If you choose to enable it, you have the possibility of disabling it for your tests like so: [tool.ruff.lint.per-file-ignores] "tests/*" = ["S101"] (Besides, this was about formatting, not linting, but I realize it's related.) [1] https://docs.astral.sh/ruff/rules/ https://docs.astral.sh/ruff/rules/