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/// Indicates unreachable code that we are confident is *truly* unreachable.
///
/// This is essentially a compromise between `core::unreachable!()` and
/// `core::hint::unreachable_unchecked()`. In debug mode builds and in tests,
/// this expands to `unreachable!()`, causing a panic. However, in release mode
/// non-test builds, this expands to `unreachable_unchecked`. Thus, this is a
/// somewhat safer form of `unreachable_unchecked` that will allow cases where
/// `unreachable_unchecked` would be invalid to be detected early.
///
/// Nonetheless, this must still be used with caution! If code is not adequately
/// tested, it is entirely possible for the `unreachable_unchecked` to be
/// reached in a scenario that was not reachable in tests.
#[macro_export]
macro_rules! unreachable_unchecked {
    () => ({
        #[cfg(any(test, debug_assertions))]
        panic!(
            "internal error: entered unreachable code \n\",
            /!\\ EXTREMELY SERIOUS WARNING: in release mode, this would have been \n\
            \x32   `unreachable_unchecked`! This could result in undefine behavior. \n\
            \x32   Please double- or triple-check any assumptions about code which \n\
            \x32   could lead to this being triggered."
        );
        #[allow(unreachable_code)] // lol
        {
            core::hint::unreachable_unchecked();
        }
    });
    ($msg:expr) => ({
        $crate::unreachable_unchecked!("{}", $msg)
    });
    ($msg:expr,) => ({
        $crate::unreachable_unchecked!($msg)
    });
    ($fmt:expr, $($arg:tt)*) => ({
        #[cfg(any(test, debug_assertions))]
        panic!(
            concat!(
                "internal error: entered unreachable code: ",
                $fmt,
                "\n/!\\ EXTREMELY SERIOUS WARNING: in release mode, this would have been \n\
                \x32   `unreachable_unchecked`! This could result in undefine behavior. \n\
                \x32   Please double- or triple-check any assumptions about code which \n\
                \x32   could lead to this being triggered."
            ),
            $($arg)*
        );
        #[allow(unreachable_code)] // lol
        {
            core::hint::unreachable_unchecked();
        }
    });
}

#[cfg(all(test, not(loom)))]
macro_rules! test_info {
    ($($arg:tt)+) => {
        tracing::trace!($($arg)+);
    };
}

#[cfg(all(test, loom))]
macro_rules! test_info {
    ($($arg:tt)+) => {
        tracing_01::trace!($($arg)+);
    };
}