generic-array 1.4.1

Generic types implementing functionality of arrays
Documentation 
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use arbitrary::Arbitrary;

use crate::{sequence::FallibleGenericSequence as _, ArrayLength, GenericArray};

impl<'a, T, N: ArrayLength> Arbitrary<'a> for GenericArray<T, N>
where
    T: Arbitrary<'a>,
{
    #[inline]
    fn arbitrary(u: &mut arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
        GenericArray::try_generate(|_| T::arbitrary(u)).unwrap_or_else(|e| match e {})
    }

    #[inline]
    fn arbitrary_take_rest(mut u: arbitrary::Unstructured<'a>) -> arbitrary::Result<Self> {
        let mut array = Self::arbitrary(&mut u)?;
        if let Some(last) = array.last_mut() {
            *last = T::arbitrary_take_rest(u)?;
        }
        Ok(array)
    }

    fn size_hint(depth: usize) -> (usize, Option<usize>) {
        Self::try_size_hint(depth).unwrap_or_default()
    }

    fn try_size_hint(
        depth: usize,
    ) -> arbitrary::Result<(usize, Option<usize>), arbitrary::MaxRecursionReached> {
        let hint = <T as Arbitrary>::try_size_hint(depth)?;

        // same as `arbitrary::size_hint::and_all(...)` but without allocations
        Ok(core::iter::repeat(hint)
            .take(N::USIZE)
            .fold((0, Some(0)), arbitrary::size_hint::and))
    }
}