buldak 0.28.1

It is a library that provides various sorting functions.
Documentation 
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//! bogo sort algorithm.
//!
//! unstable sort  
//! **best:O(1), worst:O(∞)**

/// Sort in ascending order using a bogo sort algorithm.
///
/// ```rust
/// use buldak::bogo;
///
/// let mut nums = [5, 2, 3, 4, 1];
/// bogo::sort(&mut nums);
/// assert_eq!(nums, [1, 2, 3, 4, 5]);
/// ```
pub fn sort<T>(array: &mut [T])
where
    T: std::cmp::Ord,
{
    sort_by(array, |l, r| l.cmp(r))
}

/// Sort in descending order using a bogo sort algorithm.
///
/// ```rust
/// use buldak::bogo;
///
/// let mut nums = [5, 2, 3, 4, 1];
/// bogo::sort_reverse(&mut nums);
/// assert_eq!(nums, [5, 4, 3, 2, 1]);
/// ```
pub fn sort_reverse<T>(array: &mut [T])
where
    T: std::cmp::Ord,
{
    sort_by(array, |l, r| l.cmp(r).reverse())
}

/// It takes a comparator function to determine the order,
/// and sorts it using a bogo sort algorithm.
///
/// ```rust
/// use buldak::bogo;
///
/// let mut nums = [5, 2, 3, 4, 1];
/// bogo::sort_by(&mut nums, |l, r| l.cmp(r));
/// assert_eq!(nums, [1, 2, 3, 4, 5]);
/// ```
pub fn sort_by<T, F>(array: &mut [T], compare: F)
where
    T: std::cmp::Ord,
    F: Fn(&T, &T) -> std::cmp::Ordering,
{
    _bogo_sort_impl(array, compare)
}

fn _bogo_sort_impl<T, F>(array: &mut [T], compare: F)
where
    T: std::cmp::Ord,
    F: Fn(&T, &T) -> std::cmp::Ordering,
{
    while _sorted(array, &compare) == false {
        _shuffle(array);
    }
}

fn _sorted<T, F>(array: &[T], compare: &F) -> bool
where
    F: Fn(&T, &T) -> std::cmp::Ordering,
{
    let mut current = &array[0];

    for e in array {
        match compare(current, e) {
            std::cmp::Ordering::Greater => return false,
            _ => (),
        }

        current = e;
    }

    return true;
}

use rand::seq::SliceRandom;

fn _shuffle<T>(array: &mut [T]) {
    let mut rng = rand::thread_rng();
    array.shuffle(&mut rng);
}

#[cfg(test)]
mod tests {
    #[test]
    fn sort_ascending() {
        struct TestCase {
            input: Vec<i32>,
            expected: Vec<i32>,
        }

        let test_cases = vec![TestCase {
            input: vec![1, 4, 2, 3, 5],
            expected: vec![1, 2, 3, 4, 5],
        }];

        for case in test_cases {
            let mut actual = case.input.clone();
            super::sort(&mut actual);
            assert_eq!(actual, case.expected);
        }
    }

    #[test]
    fn sort_descending() {
        struct TestCase {
            input: Vec<i32>,
            expected: Vec<i32>,
        }

        let test_cases = vec![TestCase {
            input: vec![1, 4, 2, 3, 5],
            expected: vec![5, 4, 3, 2, 1],
        }];

        for case in test_cases {
            let mut actual = case.input.clone();
            super::sort_reverse(&mut actual);
            assert_eq!(actual, case.expected);
        }
    }
}