Affected Tests:

K2-CeilngFunc-1 to -12
K2-FloorFunc-1 to -12
K2-RoundFunc-1 to -12
K2-RoundEvenFunc-17 to -22

These tests take the form

ceiling(xs:unsignedShort(3)) instanceof xs:unsignedShort

and expect the answer false. I believe this is an incorrect reading of the spec.  The spec says "If the type of $arg is a type derived from one of the numeric types, the result is an instance of the base numeric type." But if ceiling(xs:unsignedShort(3)) returns the unsignedShort 3, then this condition is satisfied, because the unsignedShort 3 is indeed an instance of "the base numeric type" (which I assume is intended to mean xs:integer).

As a general rule, if a function is required to return a value of type T, then a value of any subtype of T is acceptable.

Michael Kay