sindresorhus/eslint-plugin-unicorn

Rule proposal: Prefer `String#matchAll()`

Closed

#574 opened on Mar 3, 2020

View on GitHubContributor guide
 (6 comments) (5 reactions) (0 assignees)JavaScript (468 forks)user submission
help wantednew rule

Repository metrics

Stars
 (5,022 stars)
PR merge metrics
 (Avg merge 1d 16h) (399 merged PRs in 30d)

Description

Not offering a PR here, but just thought such a rule could possibly fit your project...

Namely, preferring String.prototype.matchAll to while loop exec assignments.

As per https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/matchAll#Examples , one can replace this:

let match;
while ((match = regexp.exec(str)) !== null) {
}

..with the likes of:

for (const match of str.matchAll(regexp)) {
}

I find it quite a bit more elegant and semantic, and it allows avoiding defining a variable in the parent block.

If not, no worries, just thought I'd see if it might pique the interest of others.

Contributor guide

Research direction
Implement a new ESLint rule that detects while loops using regexp.exec() and suggests using String.prototype.matchAll() instead. Refer to existing rules in the plugin for pattern structure, and write tests.
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.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
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 rule development
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70