// This Source Code Form is subject to the terms of the Mozilla Public

// License, v. 2.0. If a copy of the MPL was not distributed with this

// file, You can obtain one at http://mozilla.org/MPL/2.0/.

// Every codebase needs a `util` module.

use std::cmp::Ordering;

use std::ops::{Bound, Range, RangeBounds};

use archery::{SharedPointer, SharedPointerKind};

pub(crate) fn clone_ref<A, P>(r: SharedPointer<A, P>) -> A

where

A: Clone,

P: SharedPointerKind,

{

SharedPointer::try_unwrap(r).unwrap_or_else(|r| (*r).clone())

}

#[derive(Clone, Copy, PartialEq, Eq, Debug)]

pub(crate) enum Side {

Left,

Right,

}

#[allow(dead_code)]

pub(crate) fn linear_search_by<'a, A, I, F>(iterable: I, mut cmp: F) -> Result<usize, usize>

where

A: 'a,

I: IntoIterator<Item = &'a A>,

F: FnMut(&A) -> Ordering,

{

let mut pos = 0;

for value in iterable {

match cmp(value) {

Ordering::Equal => return Ok(pos),

Ordering::Greater => return Err(pos),

Ordering::Less => {}

}

pos += 1;

}

Err(pos)

}

pub(crate) fn to_range<R>(range: &R, right_unbounded: usize) -> Range<usize>

where

R: RangeBounds<usize>,

{

let start_index = match range.start_bound() {

Bound::Included(i) => *i,

Bound::Excluded(i) => *i + 1,

Bound::Unbounded => 0,

};

let end_index = match range.end_bound() {

Bound::Included(i) => *i + 1,

Bound::Excluded(i) => *i,

Bound::Unbounded => right_unbounded,

};

start_index..end_index

}

#[cfg(test)]

macro_rules! assert_covariant {

($name:ident<$($gen:tt),*> in $param:ident) => {

#[allow(unused_assignments, unused_variables)]

const _: () = {

type Tmp<$param> = $name<$($gen),*>;

fn assign<'a, 'b: 'a>(src: Tmp<&'b i32>, mut dst: Tmp<&'a i32>) {

dst = src;

}

};

}

}