Re: Tree sitter support for C-like languages

[Yuan Fu]

> On Nov 13, 2022, at 7:48 PM, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
> 
>> The parse tree has errors and it fontifies int in warning face.
>> 
>> Then when you insert the closing bracket, the parse tree is complete
>> 
>> int
>> foo (void)
>> {
>> int bar = 0;
>> }
>> 
>> Int is still in warning face because jit-lock doesn’t know it needs to be
>> refontified.
> 
> Doesn't tree-sitter tell us that the node for `int` has changed?

Yes and no, but mostly no. Tree-sitter can tell if a node “has changes”. But 
you need to keep the node updated as the buffer changes, which we currently 
don’t do. Even if we add this feature, I don’t know if “has changes” includes 
“previously inside an ERROR node but not anymore”. IIUC “has changes” means 
“corresponding text edited”. I need to add this feature and experiment with it 
to figure out what does “has changes” mean exactly.

Keeping some nodes updated (ie, “watch” those nodes) isn’t too hard to 
implement, but it wouldn’t be a trivial change. I don’t know if we want to 
introduce non-trivial changes now.

Yuan