unicorn/consistent-existence-index-check Style

🛠️ An auto-fix is available for this rule.

Enforce consistent style for element existence checks with indexOf(), lastIndexOf(), findIndex(), and findLastIndex()

This rule is only meant to enforce a specific style and make comparisons more clear.

Examples of incorrect code for this rule:

javascript

const index = foo.indexOf("bar");
if (index < 0) {
}

javascript

const index = foo.indexOf("bar");
if (index >= 0) {
}

Examples of correct code for this rule:

javascript

const index = foo.indexOf("bar");
if (index === -1) {
}

javascript

const index = foo.indexOf("bar");
if (index !== -1) {
}

References