pub fn assert_equal<I, J>(a: I, b: J) where
I::Item: Debug + PartialEq<J::Item>,
Assert that two iterables produce equal sequences, with the same semantics as equal(a, b).
Panics on assertion failure with a message that shows the two iteration elements.
assert_equal("exceed".split('c'), "excess".split('c')); // ^PANIC: panicked at 'Failed assertion Some("eed") == Some("ess") for iteration 1',