The new rules introduced in ruff v0.2.2 via #9266 are causing the ruff linter to make conflicting changes in notebook cells that the formatter is then trying to fix.

Here is an example notebook which reproduces the bug:

ruff config:

[tool.ruff]
extend-include = ["*.ipynb"]

[tool.ruff.lint]
select = [
    "E",
]

If you run the commands in this succession and look at the diffs you will notice that the linter adds two lines at the end of:

1. Cell 3 (the one just printing out the variable some_computation). This is rule E302 in action
2. Cell 4 (after the function definition). This is rule E305 in action.

The commands I ran:

1. ruff check --force-exclude --preview --fix test.ipynb
2. ruff format --force-exclude --preview test.ipynb

(The --force-exclude is because I discovered this bug through pre-commit and I was trying to mimic the pre-commit behaviour)

This behaviour happens from v0.2.2 upwards (I've also tested v0.3.0) as long as the preview flag is on.

Let me know if the MRE needs more explanation.