unicorn/prefer-array-index-of Style

🚧 An auto-fix is still under development.

What it does

Enforces using indexOf or lastIndexOf instead of findIndex or findLastIndex when the callback is a simple strict equality comparison.

Why is this bad?

Using findIndex(x => x === value) is unnecessarily verbose when indexOf(value) accomplishes the same thing more concisely and clearly. It also avoids the overhead of creating a callback function.

Examples

Examples of incorrect code for this rule:

values.findIndex(x => x === "foo");
values.findLastIndex(x => x === "bar");

Examples of correct code for this rule:

values.indexOf("foo");
values.lastIndexOf("bar");

How to use

To enable this rule in the CLI or using the config file, you can use:

CLI

oxlint --deny unicorn/prefer-array-index-of

Config (.oxlintrc.json)

{
  "rules": {
    "unicorn/prefer-array-index-of": "error"
  }
}

References

• Rule Source