collapsible-else-if

Flags an else block that only contains an if, which can be written as else if.

Why

else { if (…) { … } } behaves exactly like else if (…) { … }, with an extra level of braces and indentation.

What it flags

An else block whose only statement is an if. The inner if keeps its own else, if it has one.

What it leaves alone

• An else block with a comment next to the if, since collapsing would lose the comment.
• An else block with anything besides the if.

Example

// Before
if (a) {
    first();
} else {
    if (b) {
        second();
    } else {
        third();
    }
}

// After
if (a) {
    first();
} else if (b) {
    second();
} else {
    third();
}