#no-lonely-if

#Configuration

import { defineConfig, unicornPlugin } from '@rslint/core';

export default defineConfig([
  unicornPlugin.configs.recommended,
  {
    rules: {
      'unicorn/no-lonely-if': 'error',
    },
  },
]);

#Rule Details

Disallow an if statement as the only statement in another if without an else branch. The rule combines the conditions with &&, reducing indentation while preserving their evaluation order. It also handles statements without braces and preserves comments when fixing code.

Neither if statement may have an else branch. Other statements in the outer block prevent a report. The core no-lonely-if rule handles an if inside an else block; the two rules can be enabled together.

Examples of incorrect code for this rule:

if (ready) {
    if (enabled) {
        run();
    }
}

Examples of correct code for this rule:

if (ready && enabled) {
    run();
}

#Options

This rule has no options. It supports automatic fixes.

#Differences from upstream

Compared with eslint-plugin-unicorn v76.0.0, automatic fixes preserve the original behavior in these additional cases:

• Arrow functions used as conditions remain grouped, so the second condition is still evaluated. For example, if (x => x) { if (b) run(); } becomes if ((x => x) && b) run();.
• A statement following the merged if stays separate, including when it starts on the same line or immediately after the closing brace. For example, if (a) { if (b) run() }next() becomes if (a && b) run();next().

#Original Documentation

• eslint-plugin-unicorn: no-lonely-if
• Source code