Re: treesit indentation "blinking"

[Dmitry Gutov]

On 25/03/2023 11:05, João Távora wrote:
> On Thu, Mar 23, 2023 at 9:24 PM Dmitry Gutov <dgutov@yandex.ru> wrote:
> > On 23/03/2023 23:10, Daniel Colascione wrote:
> > > Editing can cause all sorts of transient nonsense in the AST, and it's
> > > impossible to predict in a general manner what this nonsense might be.
> > > The wrong kind of bracket can cause the entire rest of the file to be
> > > parsed as nonsense. This or that error recovery rule isn't going to
> > > solve the problem: such a strategy is a fragile whack a mole. There
> > > needs to be some general solution to prevent indentation blinking. This
> > > blinking makes TS modules unusable for me.
> >
> > It seems to me it will only be feasible to support a number of
> > "incomplete" syntax constructs. Maybe it will constitute a majority of them.
>
> I don't think this problem has anything to do with tree-sitter.  It
> would happen just as well in regular c++-mode if electric-indent-mode
> were on by default there (but it isn't).

The mode is globally on by default, but indeed the contents of 
electric-indent-chars are much shorter there.

> So it's just the fact that electric-indent-mode is on by default
> _and_ c-ts-mode.el does this:
>
> (setq-local electric-indent-chars (append "{}():;,#" electric-indent-chars))
>
> so people are getting what the mode author (and Emacs defaults) ask for:
> electric indentation doing its thing.

Good point: perhaps either this list should be revisited, or predicated 
(at runtime) somehow on electric-pair-mode being enabled.

> > Have you tried using electric-pair-mode, though? I'd hate to make it our
> > strong recommendation for all ts modes, but it does reduce the odds of
> > incomplete code a lot.
>
> Maybe you'd hate it

Not really, just a figure of speech.

But not everybody will like it, I suspect.

, but it would at least be consistent with the
> setting for electric-indent-mode, which is much more jarring.
>
> See also bug#62412 which is basically the same problem with a recipe.

Yep.