eslint/no-else-return Pedantic

🛠️ An auto-fix is available for this rule for some violations.

What it does

Disallow else blocks after return statements in if statements

Why is this bad?

If an if block contains a return statement, the else block becomes unnecessary. Its contents can be placed outside of the block.

function foo() {
  if (x) {
    return y;
  } else {
    return z;
  }
}

This rule is aimed at highlighting an unnecessary block of code following an if containing a return statement. As such, it will warn when it encounters an else following a chain of ifs, all of them containing a return statement.

Examples

allowElseIf: true

Examples of incorrect code for this rule:

function foo1() {
    if (x) {
        return y;
    } else {
        return z;
    }
}

function foo2() {
    if (x) {
        return y;
    } else if (z) {
        return w;
    } else {
        return t;
    }
}

function foo3() {
    if (x) {
        return y;
    } else {
        var t = "foo";
    }

    return t;
}

function foo4() {
    if (error) {
        return 'It failed';
    } else {
        if (loading) {
            return "It's still loading";
        }
    }
}

// Two warnings for nested occurrences
function foo5() {
    if (x) {
        if (y) {
            return y;
        } else {
            return x;
        }
    } else {
        return z;
    }
}

Examples of correct code for this rule:

function foo1() {
    if (x) {
        return y;
    }

    return z;
}

function foo2() {
    if (x) {
        return y;
    } else if (z) {
        var t = "foo";
    } else {
        return w;
    }
}

function foo3() {
    if (x) {
        if (z) {
            return y;
        }
    } else {
        return z;
    }
}

function foo4() {
    if (error) {
        return 'It failed';
    } else if (loading) {
        return "It's still loading";
    }
}

Configuration

This rule accepts a configuration object with the following properties:

allowElseIf

type: boolean

default: true

Whether to allow else if blocks after a return statement.

Examples of incorrect code for this rule with allowElseIf: false:

function foo() {
if (error) {
return 'It failed';
} else if (loading) {
return "It's still loading";
}
}

Examples of correct code for this rule with allowElseIf: false:

function foo() {
if (error) {
return 'It failed';
}

if (loading) {
return "It's still loading";
}
}

How to use

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

Config (.oxlintrc.json)

{
    "rules": {
        "no-else-return": "error"
    }
}

CLI

oxlint --deny no-else-return

References

• Rule Source