Experimental: add dom wrapper

[tafia]

This PR adds a very basic DOM like wrapper on top of quick-xml pull based reader.

The typical usage is:

use quick_xml::dom::Node;

let file = File::open(...);
let root_node = Node::root(file).expect("error while converting xml into DOM node");
let special_nodes = root_node.select_all("child1/child2/child3");
for n in special_nodes {
    println!("attributes: {}", n.attributes());
}
for n in root_node.children_mut() {
    *n.name_mut() = "My new Name".to_string();
}

[blanham]

Do you plan on merging this anytime soon?

[tafia]

I don't know. I do not really need it at the moment and I haven't been asked it. It was more a proof of concept.
Would you be interested?

[melroy89]

I'm interested, but wouldn' it be better to create a separate crate for this (probably also the reason you don't merge it into quick-xml now)? Thus also a separate git repo in this same project.

[tafia]

Yes it would definitely be better on another crate. Eventually I'd love having a crate just to declare the traits to have a DOM and several implementation (including one for quick-xml, xml-rs, xml5ever, RustyXML etc ...).

I am still struggling to find some time but if anyone wants to starts I'll be happy to help!

[melroy89]

I try to use your dom, after some hacking (like escape module is private), I now get stuck at:

error[E0382]: use of moved value: start
--> src/parse/dom.rs:340:41
|
339 | start.with_attributes(self.attributes.iter().map(|&(ref k, ref v)| (&**k, &**v)));
| ----- value moved here
340 | writer.write_event(Event::Start(start))?;
| ^^^^^ value used here after move
|
= note: move occurs because start has type quick_xml::events::BytesStart<'_>, which does not implement the Copy trait

error: aborting due to previous error

[tafia]

Sorry I haven't answered that!
This dom is really very experimental for the moment. There are definitely some pain points to fix.
For instance, reading at the error, I am not sure the writer needs to move the value. A borrow should be enough.

[tafia]

I am closing this for now as minidom crate has apparently switched to using quick-xml.

Let me know if you think otherwise.

[ColinKinloch]

I updated this code to work with the current quick-xml here.
I don't intend to continue working on it.