quickcheck_ext/
lib.rs

1#![cfg_attr(docsrs, feature(doc_cfg, doc_auto_cfg))]
2
3use core::ops::Range;
4
5use num_traits::sign::Unsigned;
6pub use quickcheck::*;
7
8pub trait GenRange {
9    fn gen_range<T: Unsigned + Arbitrary + Copy>(&mut self, _range: Range<T>) -> T;
10
11    fn gen_index(&mut self, ubound: usize) -> usize {
12        if ubound <= (u32::MAX as usize) {
13            self.gen_range(0..ubound as u32) as usize
14        } else {
15            self.gen_range(0..ubound)
16        }
17    }
18}
19
20impl GenRange for Gen {
21    fn gen_range<T: Unsigned + Arbitrary + Copy>(&mut self, range: Range<T>) -> T {
22        <T as Arbitrary>::arbitrary(self) % (range.end - range.start) + range.start
23    }
24}
25
26pub trait SliceRandom {
27    fn shuffle<T>(&mut self, arr: &mut [T]);
28    fn choose_multiple<'a, T>(
29        &mut self,
30        arr: &'a [T],
31        amount: usize,
32    ) -> std::iter::Take<std::vec::IntoIter<&'a T>> {
33        let mut v: Vec<&T> = arr.iter().collect();
34        self.shuffle(&mut v);
35        v.into_iter().take(amount)
36    }
37}
38
39impl SliceRandom for Gen {
40    fn shuffle<T>(&mut self, arr: &mut [T]) {
41        for i in (1..arr.len()).rev() {
42            // invariant: elements with index > i have been locked in place.
43            arr.swap(i, self.gen_index(i + 1));
44        }
45    }
46}
quickcheck_ext/lib.rs

quickcheck_ext/
lib.rs
