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Prefer .find(…) and .findLast(…) over the first or last element from .filter(…)

💼 This rule is enabled in the ✅ recommended config.

🔧💡 This rule is automatically fixable by the --fix CLI option and manually fixable by editor suggestions.

Array#find() and Array#findLast() breaks the loop as soon as it finds a match and doesn't create a new array.

This rule is fixable unless default values are used in declaration or assignment.

Fail

js
const item = array.filter(x => isUnicorn(x))[0];
js
const item = array.filter(x => isUnicorn(x)).at(-1);
js
const item = array.filter(x => isUnicorn(x)).shift();
js
const item = array.filter(x => isUnicorn(x)).pop();
js
const [item] = array.filter(x => isUnicorn(x));
js
[item] = array.filter(x => isUnicorn(x));

Pass

js
const item = array.find(x => isUnicorn(x));
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item = array.find(x => isUnicorn(x));
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const item = array.findLast(x => isUnicorn(x));

Options

Type: object

checkFromLast

Type: boolean
Default: true

Pass checkFromLast: false to disable check cases searching from last.

Pass

js
// eslint unicorn/prefer-array-find: ["error", {"checkFromLast": false}]
const item = array.filter(x => isUnicorn(x)).at(-1);
js
// eslint unicorn/prefer-array-find: ["error", {"checkFromLast": false}]
const item = array.filter(x => isUnicorn(x)).pop();

Released under the Apache License 2.0.