Improve warnings when ignoring preview rules without preview flag

[bersbersbers]

ruff check --isolated --ignore PLC1901,PLR0904  # version 0.0.290

outputs

warning: Selection of nursery rule `PLC1901` without the `--preview` flag is deprecated.
warning: Selection `PLR0904` has no effect because the `--preview` flag was not included.

I think these warnings are rather irrelevant - they basically confirm what the users wants to do anyway, which is not select these rules.

[silverwind]

Also noticed this strange warning. I had PLC1901 in my ignore config for a long time (because it's a unsafe rule), ruff v0.0.290 now suddenly started warning about it.

[hmvp]

Also noticed this strange warning. I had PLC1901 in my ignore config for a long time (because it's a unsafe rule), ruff v0.0.290 now suddenly started warning about it.

That rule moved to the nursery, probably because its unsafe... We had the same..

[silverwind]

Does nursery mean it's disabled by default now when I select=["PL"]?

[charliermarsh]

@silverwind - Yeah, if you do select=["PL"], PLC1901 will not be included.

[silverwind]

Thanks, I'll remove it then from ignore and I see the warning also makes sense. It should probably explain better what the "nursery" is, the online docs also have no info on this topic.

[charliermarsh]

"Nursery" was changed to "Preview" -- we should probably update the docs to reflect that it used to be called "Nursery".

[silverwind]

I see. Maybe just reword the warning to something like this?

warning: Ignoring preview rule `<id>` has no effect unless `--preview` is specified.

[charliermarsh]

\cc @zanieb - when you're back :)

[zanieb]

"select" is kind of a broad term in this warning, we're referring to the use of a rule selector which can be used with any of the command line options e.g. --select / --ignore. I figured this would be a little ambiguous and we could improve it with more careful messaging in a follow-up — thanks for your feedback!

[frenck]

Just ran into this on the Home Assistant project. Honestly, I don't think this is a messaging problem.

A rule was ignored explicitly and still gives us this warning. Meaning if you run it with --preview, it still was ignored. But that is now something we should not do anymore?

It is a bit odd as we don't want it in preview but also want to ignore it if it gets out of preview/nursery.

I'm not sure why an ignore flag has to trigger this warning. What is the goal for triggering the warning in that case? What is the risk if it would still be set to be ignored while only available in preview?

I'm just confused about what problem is solved here and why this warning is added for this specific case reported in this issue.

../Frenck

[zanieb]

Hey @frenck

The implementation is just naively collecting all of the selector options e.g.

ruff/crates/ruff_workspace/src/configuration.rs

Lines 703 to 712 in 316f759

	for selector in selection
	.select
	.iter()
	.chain(selection.fixable.iter())
	.flatten()
	.chain(selection.ignore.iter())
	.chain(selection.extend_select.iter())
	.chain(selection.unfixable.iter())
	.chain(selection.extend_fixable.iter())
	{

This warning is not explicitly targetting use of --ignore <RULE>, it applies to any option in which <RULE> is used. This was just the simplest way to implement the warning alongside our existing warnings, but we can update that iterator to be aware of the specific option used to remove or reword the message as needed.

I'll be working on this soon.