[Feature request] expect_permutation

[sebffischer]

I looked at the uses of expect_set_equal in my own code, as well as in the mlr repositories and it seems that in quite some cases where we currently use the function, what we actually want to test is whether the two objects are permutation-equivalent and not set-equivalent, in the sense that

expect_set_equal(c("a", "b", "a"), c("a, "b")) # does not fail but should fail

# this should be replaced with
expect_permutation(c("a", "b", "a"), c("a, "b")) # fails!

[sebffischer]

I can make a PR if you think this would be useful

[mllg]

Sounds good to me.

[sebffischer]

Created a PR https://github.com/mllg/checkmate/pulls