Rule proposal: `proper-object-iterable-methods`

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Description

// Should use `Object.values`
for (const key of Object.keys(foo)) {
	bar(foo[key]);
}

// Should use `Object.entries`
for (const key of Object.keys(foo)) {
	bar(foo[key], key);
}

// Should use `Object.values`
const foo = Object.keys(bar).map(key => baz(bar[key]));

// Should use `Object.entries`
const foo = Object.keys(bar).map(key => baz(bar[key], key));

// Should use `Object.keys`
for (const [key] of Object.entries(foo)) {
	bar(key);
}

for (const key of Object.keys(foo)) {
	foo[key] = 'new value';
	delete foo[key];
	foo[key]++;
}

Contributor guide

Research direction

First, examine existing rules in eslint plugin unicorn (e.g., `prefer object spread`) to understand the rule structure and AST helpers. The new rule should detect patterns like `for (const key of Object.keys(foo)) { bar(foo[key]); }` and suggest `for (const value of Object.values(foo)) { bar(value); }`. Also detect `Object.keys().map()` and suggest `Object.values()` or `Object.entries()`. For reverse case, detect `Object.entries()` used only for keys and suggest `Object.keys()`. Edge cases include mutations like assignment or delete on `foo[key]`, which should not trigger the rule. Implement auto fix where safe. Write tests covering all fail and pass examples from the issue.

Tech stack

javascript

Domain

developer experiencetooling

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.

Stale

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

Clear

Prerequisites

ESLint plugin developmentAST knowledgeJavaScript

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

60