if statements return all arguments on no matching conditions

[jqr]

When an if statement doesn't match on any of it's conditions, it returns all arguments instead of nil as expected:

JSONLogic.apply({ "if" => [false, 1] }, {})            # => [false, 1]            (expected nil)
JSONLogic.apply({ "if" => [false, 1, false, 2] }, {})  # => [false, 1, false, 2]  (expected nil)

Background

if generally has the form [condition1, value1, condition2, value2, ...] and the first condition to be truthy returns the associated value, and if no conditions match null is returned.

{ "if": [false, 1] }            // => null
{ "if": [false, 1, true, 2] }   // => 2
{ "if": [false, 1, false, 2] }  // => null

There is a special case with an odd number of arguments [condition1, value1, condition2, value2, value_else] where the value_else is returned if none of the previous conditions match.

{ "if": [false, 1, 2] }            // => 2
{ "if": [false, 1, false, 2, 3] }  // => 3