assertion for tablePattern

[grewered]

added assertion for vector x.

I wasn't sure about the rest of the function.
does pattern need assertions? And what kind of values should be allowed/sensible?

what does useNA do? with useNA = c("no", "ifany", "always")) as default.
It's not used in the example, so do you even change that argument?
do you use of of the three options, and shall i write a test, whether one of them has been chosen - or just leave it be?

[weirichs]

checkmate::assert_vector(x) is fine.

pattern may need assertions if it is not null. So you can add after if(length(pattern)>0) { a line with checkmate::assert_vector(pattern)

useNA is an argument which is directly passed to the table function. This argument is not changed within the function, so it does not need assertation.

In general, a possible test that the user chooses one of the three options (where abbreviations are allowed), is:

useNA <- match.arg(useNA, choices = c("no", "ifany", "always"))

But again, that's not necessary here.

If weights is not missing (i.e. line 24), you might add an assertation that weights is a numeric vector with length equal to the length of x.

[weirichs]

LGTM, in general.
I don't know whether it's possible, but pattern should be a vector with unique elements, i.e. something like pattern = c(1, 2, 3, 1) is inappropriate. I don't know whether checkmate provides corresponding assertations. If not, everything can stay as it is.
Alternatively, you could add pattern <- unique(pattern) between line 7 and 8.

I'm not sure whether you should point out to users that pattern must be unique, or whether you should change this silently in the function code.

What would you prefer?

[grewered]

like this? checking for uniqueness with checkmate is usually very easy.

[weirichs]

Very well, thanks!