rust/src/libcoretest/slice.rs
Brian Anderson a4b354ca02 core: Add binary_search and binary_search_elem methods to slices.
These are like the existing bsearch methods but if the search fails,
it returns the next insertion point.

The new `binary_search` returns a `BinarySearchResult` that is either
`Found` or `NotFound`. For convenience, the `found` and `not_found`
methods convert to `Option`, ala `Result`.

Deprecate bsearch and bsearch_elem.
2014-08-13 11:30:15 -07:00

36 lines
1.4 KiB
Rust

// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::slice::{Found, NotFound};
#[test]
fn binary_search_not_found() {
let b = [1i, 2, 4, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&6)) == Found(3));
let b = [1i, 2, 4, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&5)) == NotFound(3));
let b = [1i, 2, 4, 6, 7, 8, 9];
assert!(b.binary_search(|v| v.cmp(&6)) == Found(3));
let b = [1i, 2, 4, 6, 7, 8, 9];
assert!(b.binary_search(|v| v.cmp(&5)) == NotFound(3));
let b = [1i, 2, 4, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&8)) == Found(4));
let b = [1i, 2, 4, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&7)) == NotFound(4));
let b = [1i, 2, 4, 6, 7, 8, 9];
assert!(b.binary_search(|v| v.cmp(&8)) == Found(5));
let b = [1i, 2, 4, 5, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&7)) == NotFound(5));
let b = [1i, 2, 4, 5, 6, 8, 9];
assert!(b.binary_search(|v| v.cmp(&0)) == NotFound(0));
let b = [1i, 2, 4, 5, 6, 8];
assert!(b.binary_search(|v| v.cmp(&9)) == NotFound(6));
}