In the rust test, I don't care about the sequence of vec![]. What should i do?

Question

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Is there any disorderd arrays Or Do not judge the order when asserting?

Answer 1

What I do is sort both sides in the assert call itself. This only works if T implements Ord.

let result = my_function();
my_function.sort();
let target = vec![];
target.sort();

assert_eq!(result, target);

If your datatype does not support Ord, you can use sort_by with a FnMut that returns an instance of Ordering.

Note that this can have issues when there isn't one specific way a vector can be sorted.

Answer 2

Convert the Vec(s) to HashBag(s) that contains references to the items in the Vecs. That will disregard the order of items when asserting for equality:

[dependencies]
hashbag = "0.1.9"

#[test]
fn two_vecs_equal_independent_of_item_order() {
    use hashbag::HashBag;

    let actual = vec![1, 2, 3, 3];

    let expected_fail = vec![3, 2, 1];

    assert_ne!(
        actual.iter().collect::<HashBag<&i32>>(),
        expected_fail.iter().collect::<HashBag<&i32>>()
    );

    let expected_pass = vec![3, 2, 1, 3];

    assert_eq!(
        actual.iter().collect::<HashBag<&i32>>(),
        expected_pass.iter().collect::<HashBag<&i32>>()
    );

}