Tracking Issue for #![feature(non_exhaustive_omitted_patterns_lint)]

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This is a tracking issue for the non_exhaustive_omitted_patterns lint.
The feature gate for the issue is #![feature(non_exhaustive_omitted_patterns_lint)].

About tracking issues

Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.
A tracking issue is however not meant for large scale discussion, questions, or bug reports about a feature.
Instead, open a dedicated issue for the specific matter and add the relevant feature gate label.

In terms of the "documentation" bullet-point, the lint should turn up automatically on that list and I think that's enough. So we'll only need to check that it says the right thing once we've ironed out the name and message etc.

The question about not filtering doc(hidden) (and maybe this was only me feeling like it was odd) is kind of resolved for me since we unified the behavior so I no longer have the argument that filtering doc(hidden) variants/fields out of error and warning messages is not the norm (now it is done for all exhaustiveness checking).

I'm also curious about the stability of warning/error messages, I assume rust makes no guarantee so they can be improved quickly.

Yeah, don't think there's any formal guarantee and they do change in small ways regularly

Auto merge of rust-lang#90358 - DevinR528:omitted-field-fix, r=jackh726

Update dependencies

I discovered something cool today: non_exhaustive_omitted_patterns will warn in the following case if we add variants to Enum, which an exhaustiveness-based check wouldn't catch:

#[warn(non_exhaustive_omitted_patterns)]
match (x, y) {
    (Enum::A, Enum::A) => true,
    (Enum::B, Enum::B) => true,
    _ => false,
}

I kind of want this for arbitrary enums now.

Maybe this could be a general #[warn(mention_all_variants_of(Enum))]

There is a false positive involving the standard library matches! macro: #135137

I wonder if there's a missing piece here where we should have warn-by-default: if one of the omitted fields are a #[must_use] type?

That seems to be a much more general feature request: currently we don't do anything particular with must_use in patterns at all. Feel free to open a feature request for that.

#135137 = #117304 was resolved back in July, the only thing left seems to be stabilization?

Has there been any discussion on the unresolved questions? If nobody's saying anything they don't seem critical.

I'd very like to see this stabilized too, regardless of the name. I've been bitten by missed critical cases a few too many times now.

Yeah this would need stabilization work; I'm not sold on the name nor design of this though, I'm hoping someone would have better ideas. I also kinda think this would fit better as a clippy lint. This was implemented in the compiler because it requires access to some match exhaustiveness logic, but the match exhaustivenesss logic has been librarified into a reusable crate now (r-a uses it!) so this could be moved to clippy now.

Add missing error variant conversion (#7628)

Add missing error variant conversion (unicode-org#7628)

feat(core): Story 1.3 — StepTimeoutFired event + workspace non_exhaus…

docs(architecture): correct unstable-lint MSRV claim + mark aspiratio…

review(governance): address bugbot/meroreviewer comments on phase 1+2

fix(strict-lint): enable non_exhaustive_omitted_patterns feature on p…

The second-to-last step in the issue description can be closed, I fixed it last year in #144331.

Now it's just a matter of somebody taking care of the stabilization :)

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Tracking Issue for `#![feature(non_exhaustive_omitted_patterns_lint)]` #89554

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Tracking Issue for #![feature(non_exhaustive_omitted_patterns_lint)] #89554

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DevinR528 commented on Oct 7, 2021

Nadrieril commented on Oct 11, 2021

DevinR528 commented on Oct 13, 2021

Nadrieril commented on Oct 13, 2021

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Nadrieril commented on Dec 8, 2023

Nadrieril commented on Dec 8, 2023

dtolnay commented on Jan 5, 2025

jonhoo commented on Oct 21, 2025

Nadrieril commented on Nov 5, 2025

andrewbaxter commented on Nov 28, 2025

Nadrieril commented on Nov 30, 2025

jplatte commented on Aug 3, 2026

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Tracking Issue for `#![feature(non_exhaustive_omitted_patterns_lint)]` #89554