lxml instead of libxml2?

[jiapei100]

Hi:

It looks Python now moves to support lxml, instead of libxml2? So, I wonder if itstool can also change from libxml2 support to lxml support?

Cheers

[shaunix]

Doubtful. libxml2 gives a pretty unprecedented level of access to the XML, and itstool uses this extensively, because what it's doing to XML is non-trivial. IIRC, I even had to land new features in the libxml2 Python bindings to do everything itstool does. Feel free to take a crack at it, though.

[jiapei100]

@shaunix Oh, Hi, shaunix...
I noticed your pull request at https://github.com/itstool/itstool/pull/3
Great topic...
It will take sometime to shift from libxml2 to liblxml though. Let me try...

[heftig]

libxml2's Python bindings are insane because they require the program to manually free the document memory.

I recommend migrating away from either libxml2 or Python posthaste.

[concatime]

@shaunix so, neither xml nor lxml can replace libxml2 for itstool’s usecase?

[shaunix]

I don't really know. An important consideration is XPath support. I did recently switch yelp-tools to lxml, using some XPath:

https://gitlab.gnome.org/GNOME/yelp-tools/-/blob/master/tools/yelp-check.in

I remember running into some XPath problems, and I don't remember the details. That code is just using XPath to extract some info, and isn't doing the kind of document rewriting that itstool does. The way lxml handles text nodes doesn't really line up with the XPath data model, so that could be an issue.

It might be doable. I'd certainly welcome not having to do manual memory management in Python anymore (ugh). But it would take me a considerable amount of development time to figure it out, and I just don't have bandwidth for that right now. If someone else wants to take a crack at it, I'll try very hard to prioritize reviewing their work.