== Why is this an issue?

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.


=== Noncompliant code example

[source,javascript]
----
function foo(a) {  // Noncompliant
  if (a === 1) {
    return true;
  }
  return 3;
}
----


=== Compliant solution

[source,javascript]
----
function foo(a) {
  if (a === 1) {
    return true;
  }
  return false;
}
----


=== Exceptions

Functions returning ``++this++`` are ignored.

[source,javascript]
----
function foo() {
  // ...
  return this;
}
----

Functions returning expressions having type ``++any++`` are ignored.

ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Refactor this function to always return the same type.


=== Highlighting

Primary: function name/declaration

Secondary: Return statements


endif::env-github,rspecator-view[]