Rule proposal: `prefer-string-pad-start-end`

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Description

bar = '12345';
'0'.repeat(4 - bar.length) + bar;
VM433:2 Uncaught RangeError: Invalid count value
    at String.repeat (<anonymous>)

bar = '12345';
bar.padStart(4, '0');
'12345'

const foo = ' '.repeat(10 - bar.length) + bar;

const foo = '*'.repeat(10 - bar.length) + bar;

const foo = bar + ' '.repeat(10 - bar.length);

const foo = bar + '*'.repeat(10 - bar.length);

const foo = ('*'.repeat(10) + bar).slice(-10);

const foo = (bar + '*'.repeat(10)).slice(0, 10);

const foo = bar.padStart(10)

const foo = bar.padStart(10, '*')

const foo = bar.padEnd(10)

const foo = bar.padEnd(10, '*')

Contributor guide

Research direction

Examine existing ESLint rules in eslint plugin unicorn for structure, then use AST selectors or traversals to detect patterns like `' '.repeat(N bar.length) + bar`, `bar + ' '.repeat(N bar.length)`, and `('*'.repeat(N) + bar).slice( N)` and suggest `padStart`/`padEnd`.

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.

Active

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

Clear

Prerequisites

JavaScriptESLint plugin development

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

65