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Rslint

    prefer-array-last-methods

    Added in v0.9.4

    Configuration

    PresetConfigured Value
    ✅ unicornPlugin.configs.recommended"error"
    rslint.config.ts
    import { defineConfig, unicornPlugin } from '@rslint/core';

export default defineConfig([
  unicornPlugin.configs.recommended,
  {
    rules: {
      'unicorn/prefer-array-last-methods': 'error',
    },
  },
]);

    Prefer last-oriented array methods over reversing an array and then calling the corresponding forward method.

    The rule recognizes:

    • .reverse().find() and .toReversed().find() → .findLast()
    • .reverse().findIndex() and .toReversed().findIndex() → .findLastIndex()
    • .reverse().indexOf() and .toReversed().indexOf() → .lastIndexOf()
    • .reverse().reduce() and .toReversed().reduce() → .reduceRight()
    // Incorrect
const result = array.reverse().find(isUnicorn);

// Correct
const result = array.findLast(isUnicorn);

    The rule reports a diagnostic and offers an editor suggestion rather than an automatic fix because replacing reversal can change observable mutation, sparse-array, callback-index, or index-return semantics. Suggestions are withheld when comments occur inside the matched call.

    This port follows eslint-plugin-unicorn v75.0.0.