#array-callback-return

#Configuration

import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'array-callback-return': 'error',
    },
  },
]);

#Rule Details

Enforces return statements in callbacks of array methods such as map, filter, find, findIndex, findLast, findLastIndex, every, some, reduce, reduceRight, flatMap, sort, toSorted, and Array.from. Callbacks for these methods must return a value; otherwise, the code likely contains a mistake.

#Options

• allowImplicit (default: false): When set to true, allows callbacks to implicitly return undefined by using return; without a value.
• checkForEach (default: false): When set to true, also checks that forEach callbacks do not return a value.
• allowVoid (default: false): When set to true along with checkForEach, allows forEach callbacks to return void expressions (e.g., void bar(x)).

Examples of incorrect code for this rule:

var squares = [1, 2, 3].map(function (x) {
  x * x;
});

var bools = [1, 2, 3].filter(function (x) {
  if (x > 2) {
    return true;
  }
  // missing return in else path
});

// with checkForEach: true
[1, 2, 3].forEach((x) => x * x);

Examples of correct code for this rule:

var squares = [1, 2, 3].map(function (x) {
  return x * x;
});

var bools = [1, 2, 3].filter(function (x) {
  return x > 2;
});

[1, 2, 3].forEach((x) => {
  console.log(x);
});

// with checkForEach: true and allowVoid: true
[1, 2, 3].forEach((x) => void bar(x));

#Original Documentation

• ESLint array-callback-return