no-lonely-if

Disallow if statements as the only statement in else blocks

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:

/*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:

/*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

• Rule source
• Tests source