Rule proposal: Use `Array#includes()` instead of repeated conditional checks

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Description

const [, , ...args] = process.argv;
if (args[0] === '-h' || args[0] === '--help') {
  outputHelp();
} 

const [, , ...args] = process.argv;
if (['-h', '--help'].includes(args[0])) {
  outputHelp();
}

Contributor guide

Research direction

Implement the rule 'use array includes' that checks for multiple conditional OR checks with the same variable and suggests using Array.includes(). Refer to existing rules like 'prefer includes' or similar in the eslint plugin unicorn repository. Look at rule implementation files in `rules/` directory. The rule should use an AST selector for `IfStatement` and check the test for patterns like `a === b || a === c`. Provide a fixer to replace with `[b, c].includes(a)`.

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.

Half day

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

Stale

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

Mostly clear

Prerequisites

Basic knowledge of ESLint rulesFamiliarity with AST selectorsUnderstanding of array methods

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

50