unicorn/prefer-array-find Perf ​
What it does ​
Encourages using Array.prototype.find instead of filter(...)[0] or similar patterns when only the first matching element is needed.
Why is this bad? ​
Using filter(...)[0] to get the first match is less efficient and more verbose than using find(...). find short-circuits when a match is found, whereas filter evaluates the entire array.
Examples ​
Examples of incorrect code for this rule:
js
const match = users.filter(u => u.id === id)[0];
const match = users.filter(fn).shift();Examples of correct code for this rule:
js
const match = users.find(u => u.id === id);
const match = users.find(fn);How to use ​
To enable this rule in the CLI or using the config file, you can use:
bash
oxlint --deny unicorn/prefer-array-findjson
{
"rules": {
"unicorn/prefer-array-find": "error"
}
}