False positive for infinite_iter

[michael-p]

The following code causes clippy to trigger the infinite_iter lint but it's perfectly fine since ArrayVec only takes a limited amount (10 in this case) of items from the iterator (see ArrayVec documentation

use arrayvec::ArrayVec;
use std::iter;

fn main() {
    let stuff: ArrayVec<[u8; 10]> = iter::repeat(22).collect();
    println!("{:?}", stuff); // -> [22, 22, 22, 22, 22, 22, 22, 22, 22, 22]
}

Note that infinite_iter is set to deny by default, causing compilation to abort with an error.

Clippy version: clippy 0.0.212 (2e26fdc2 2018-11-22)

[oli-obk]

We should limit the lint to

• Vec
• VecDeque
• BTreeSet, BTreeMap
• HashSet, HashMap

which are known to be infinitely allocating on infinite iterators.

[michael-p]

Sounds good to me! Should probably also include LinkedList and BinaryHeap, for the sake of completeness.