New lint: `while let Some(&x) = slice.iter().next()` is infinite loop

Description

fn main() {
    let a = [1, 2, 3];
    while let Some(&x) = a.iter().next() {
        println!("{:?}", x);
    }
}

Contributor guide

Tech stack

rust

Domain

tooling

Issue type

feature

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

half day

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

blocked

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

clear

Prerequisites

basic Rustunderstanding of Rust iteratorsfamiliarity with Clippy's lint creation guide

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

35

Research direction

This issue requests a new lint to detect infinite loops caused by `while let Some(&x) = slice.iter().next()`. The pattern should match any iterator that is not consumed in the loop. To implement, look at existing lints in `clippy lints/src/` for similar pattern matching, especially those using `MatchSource::WhileLet`. The issue is assigned to katlasik, so coordinate with them before starting work. Check for any existing PRs or comments for updated design decisions.