Unit testing provides the developer with a number of methods called assertion methods:
#[test]
fn multiply()
{
assert_eq!(5, 2 * 3);
}
In the preceding code snippet, we use the assert_eq! (assert equal) macro. The first argument is the answer expected, and the second argument is what is being tested. If 2 * 3 = 5, then the assertion is true and passes the unit test.