The prefer-array-methods rule

This document is the reference of the prefer-array-methods rule: its options, the loops it judges, and the diagnostics it produces. The rule is written against the vibator.recommended namespace.

Reference

• Configuration: The options the rule accepts.
• Detection: The loops it judges.
• Diagnostics: One finding per replaceable loop.
• Fix: Why there is none.

---

Configuration

The rule id is prefer-array-methods. It defaults to warn. Configure it in .vibator.json:

{
  "plugins": [
    "@vibator/recommended"
  ],
  "rules": {
    "prefer-array-methods": {
      "options": {
        "include": ["src/**/*.{ts,tsx}"]
      }
    }
  }
}

Option	Description
include / exclude	The shared vibator scope globs. exclude adds **/*.d.ts: declaration files carry no loops.

Detection

The rule judges for, for-of, and for-in loops through vibator.recommended.manualLoops: a loop is reported when its body is a single statement with no break, continue, return or await. Nested functions are not descended into, so control flow inside a callback does not excuse the outer loop. vibator-ignore prefer-array-methods markers are honored at file level and on the loop or any enclosing scope.

Diagnostics

One diagnostic per replaceable loop, on the line the loop starts on.

Fix

Which array method fits (forEach, map, filter, flatMap, reduce) depends on what the loop means, and the check is syntactic: a loop over a Set or a generator has no direct rewrite at all. The rule ships as warn for the same reason, and implements no fix hook.