Unlike strongly typed languages, JavaScript does not enforce a return type on a function. This means that different paths through a function can return different types of values, which can be very confusing to the user and significantly harder to maintain.
function foo(a) { // Noncompliant
if (a === 1) {
return true;
}
return 3;
}
function foo(a) {
if (a === 1) {
return true;
}
return false;
}