Function assert_contains_not 

pub fn assert_contains_not<H, N>(needle: N, haystack: H)
where
    H: Container + Debug,
    N: Borrow<H::Item>,
    H::Item: Debug,

Assert that a haystack does not contain the given needle.

Uses the Container abstraction so it works with slices, vectors, sets, maps (by key), strings, and ranges. The error message includes both the container and the item for quick debugging.

Panics

Panics if haystack.contains(needle) returns true.