Function run_tests 

pub fn run_tests<F>(
    opts: &TestOpts,
    filtered_tests: Vec<TestDescAndFn>,
    all_tests_len: usize,
    notify_about_test_event: F,
) -> Result<()>
where
    F: FnMut(TestEvent) -> Result<()>,

🔬This is a nightly-only experimental API. (test)