In the description, , appears to be in the list of eyes - it is not, it just appears to be.
Maybe remove the commas (and maybe the ors?) from the list of emoticon parts...?

Java translation

Test for handler (\, True,False): 'KeyError' should equal '\'
Why should NOT string equal string and also why backslash should equal two backslahes? I dont see logic in this
P.s. sory for my bad english, i hope you understood

Description should be language-agnostic

Trivial arithmetic is not a novel kata idea.

If all relevant values are 0 and we should return 0.5, nothing has been tested, right? Is it useful to calculate an F-score under those circumstances?

Why is this one approved again? Don't we have enough rotational katas already in store ? Seems like many consider changing the input from array to string will make this one unique -_-

You might as well lose the numbers from the description; they only confuse. I thought I had to return numbers instead of letters until I saw the example tests.

Please lose the input validation. There is no good reason for it.

In my opinion, the kata is artificial and uninspired. There's not a lot to be done about that. It might be a duplicate, but I haven't actually looked. Technically, it's well done, so keep an eye on your satisfaction rating to see if there's a future for the kata.

Duplicate.

Subtracting
[9, 3, 2, 1, 1] -> [9, 9-3, 9-3-2, 9-3-2-1, 9-6-2-1-1] -> [9, 6, 4, 3, 3] 

This example is wrong.

Input validation is a worthless requirement and should be removed. The way invalid inputs are supposed to be handled is also broken, as it's impossible to distinguish the result of a valid call with an empty list from the result of an invalid call.

"func" must be a function

The reference solution ignores this rule for lists with 1 element.

' ' is not tested. It should be.

Returning inconsistent datatypes is not a best practice.

Consider asking for throwing an Error, instead of returning a string instead of a single character. ( There are languages that - correctly - make this distinction! )

Please, remove the parsing requirement, and make the input a pair of integers: base and value. The output should ideally be a 4-tuple of numbers too.

'1 + log9(6)' should equal '3/2 + 1/2log3(2)'

Beg you pardon!???
Nothing in the description about that... (the gap between the description and the actual task is even worse than before... :/ )