Rule proposal: Prefer array `last` methods over `reverse`

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Description

array.reverse().find(logic);
array.reverse().findIndex(logic);
array.reverse().indexOf(logic);
array.reverse().reduce(logic);
array.toReversed().find(logic);
array.toReversed().findIndex(logic);
array.toReversed().indexOf(logic);
array.toReversed().reduce(logic);

array.findLast(logic);
array.findLastIndex(logic);
array.lastIndexOf(logic);
array.reduceRight(logic);

Contributor guide

Research direction

This issue proposes a new ESLint rule to prefer array last methods (findLast, findLastIndex, etc.) over reverse(). The implementation should follow the pattern of existing rules in the eslint plugin unicorn repository, such as prefer array find. Key files to modify include the rule source file in the 'rules' directory and corresponding test files. The rule should parse method calls on arrays and check for reverse or toReversed followed by find/findIndex/indexOf/reduce. Look at existing rules for guidance on AST traversal and fix suggestions.

Tech stack

javascript

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.

1-2 days

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

Active

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

Clear

Prerequisites

JavaScriptESLint plugin development basics

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

60