Here is my result:

when you click the button, I record a srart time. after all tests(1500 random tests and a few fixed tests) finished, I record another time, and then end time - start time, finally I got a time value.

The reason? ;-)
Because some "evil" user wrote memorizing programming code, which is not the way I want. It calculates the value of each year in the range(1000..275760) and stores them in an array. The whole process needs 3000-4000ms. Of course, if this kata is not a challenge edition, this is a valid solution.
However, the solution I want should be able to quickly calculate each result. This is the significance of the challenge.
Of course, if I increase the range of years, such a solution will be timeout. However, if I do this, I will hear some users complain that "the number of years is exceed the range of JS Date()!"
So, my way is set a time limit 500ms to ban such solutions.

What do you do to the void case?

What do you do to the void case?

I'm getting this failure as well, if the pass/fail properties are not magicArrays then the chainable tests will fail, otherwise the getSplit test will fail. Any suggestions?

EDIT: durr, just needed to define the method props as non-enumerable :)

Did you trip over enumerability of methods? Or do you have magicArrays that aren't arrays?