Select and Text are not fused iterators

[Noname-Official]

use scraper::{Html, Selector};

const HTML: &str = r"
<div>
    <p>Hello</p>
    <p>World</p>
</div>
";

let html = Html::parse_fragment(HTML);
let selector = Selector::parse("div").unwrap();
let div = html.select(&selector).next().unwrap();
let selector = Selector::parse("p").unwrap();
let mut elements = div.select(&selector);
assert!(elements.next().is_some());
assert!(elements.next().is_some());
assert!(elements.next().is_none());
assert!(elements.next().is_some());

[adamreichold]

Sorry for introducing this bug and thank you for fixing it! I think I made the wrong assumption here that Traverse would be fused, but it reuses its initial state as its final state and therefore just restarts iterating the subtree after completing it once.

I do think it would be better to fix Traverse, e.g. make it fused by giving it a root: Option<NodeRef<'a, T>> field that is set to None once iteration is complete to differentiate its initial and final state (without increasing its size). But I fear, if we ever want to make changes to ego-tree, we'll have to fork it as the author seems unresponsive, so this certainly is the better short-term fix.

[cfvescovo]

Merging this as a temporary fix