duskphantom_utils/
vec_util.rs

1// Copyright 2024 Duskphantom Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14//
15// SPDX-License-Identifier: Apache-2.0
16
17use anyhow::Result;
18
19pub fn insert_vec<T: Clone>(vec: &mut Vec<T>, mut to_insert: Vec<(usize, T)>) -> Result<()> {
20    if to_insert.is_empty() {
21        return Ok(());
22    }
23    to_insert.sort_by(|a, b| a.0.cmp(&b.0));
24    assert!(to_insert[0].0 < vec.len());
25    let mut new_vec = Vec::with_capacity(vec.len() + to_insert.len());
26    for (i, item) in vec.iter().enumerate() {
27        while let Some((index, _)) = to_insert.first() {
28            if index == &i {
29                let (_, to_insert_item) = to_insert.remove(0);
30                new_vec.push(to_insert_item);
31            } else {
32                break;
33            }
34        }
35        new_vec.push(item.clone());
36    }
37    *vec = new_vec;
38
39    Ok(())
40}
41
42#[cfg(test)]
43mod tests {
44    use super::*;
45
46    #[test]
47    fn test_insert_vec() {
48        let mut vec = vec![1, 2, 3, 4, 5];
49        insert_vec(&mut vec, vec![(0, 0), (2, 2), (4, 4)].into_iter().collect()).unwrap();
50        assert_eq!(vec, vec![0, 1, 2, 2, 3, 4, 4, 5]);
51    }
52}