no-lonely-if

Disallow if statements as the only statement in else blocks

🔧

Some problems reported by this rule are automatically fixable by the --fix command line option

If an if statement is the only statement in the else block, it is often clearer to use an else if form.

if (foo) {
    // ...
} else {
    if (bar) {
        // ...
    }
}
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should be rewritten as

if (foo) {
    // ...
} else if (bar) {
    // ...
}
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Rule Details

This rule disallows if statements as the only statement in else blocks.

Examples of incorrect code for this rule:

Open in Playground

/*eslint no-lonely-if: "error"*/

if (condition) {
    // ...
} else {
    if (anotherCondition) {
        // ...
    }
}

if (condition) {
    // ...
} else {
    if (anotherCondition) {
        // ...
    } else {
        // ...
    }
}
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Examples of correct code for this rule:

Open in Playground

/*eslint no-lonely-if: "error"*/

if (condition) {
    // ...
} else if (anotherCondition) {
    // ...
}

if (condition) {
    // ...
} else if (anotherCondition) {
    // ...
} else {
    // ...
}

if (condition) {
    // ...
} else {
    if (anotherCondition) {
        // ...
    }
    doSomething();
}
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When Not To Use It

Disable this rule if the code is clearer without requiring the else if form.

Version

This rule was introduced in ESLint v0.6.0.

Resources

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