bug#71562: treesit-install-language-grammar fails to install typescript

[Eli Zaretskii <eliz@gnu.org>]

> Date: Thu, 20 Jun 2024 18:03:32 +0300
> Cc: casouri@gmail.com, sb@dod.no, 71562@debbugs.gnu.org
> From: Dmitry Gutov <dmitry@gutov.dev>
> 
> On 20/06/2024 14:31, Eli Zaretskii wrote:
> 
> >>> And what do you think should happen next?  Or where's the problem in
> >>> the above 3 steps?
> >>
> >> Next he presses RET a few times and the installation fails.
> > 
> > Why would it fail, if my suggestion is implemented?
> 
> Because your suggestion is for the case where Bob specifies 'typescript' 
> on step 3.

No, it was for _any_ grammar, regardless of its name.

> >> If we added two entries to treesit-language-source-alist by default,
> >> OTOH (one for typescript, and another for tsx), then Bob would be able
> >> to install the grammar easily.
> > 
> > But then we'd need to maintain a DB of all the "abnormal" repositories
> > (and there a few of them),
> 
> There are not too many of them, and out of those TypeScript (and TSX 
> with it) is more popular than most of the others as a programming 
> language. So even if we add these two it wouldn't follow that we must 
> have the rest.

They are not too many, but they tend to grow, and maintaining such a
list would be an extra burden.  Why do that when a simpler and more
reliable solution exists?

> If we aren't concerned about side-effects, such as for example when the 
> user wanted to stay on the previous version of the tsx grammar they had 
> installed (because the major mode doesn't work with the newer one), but 
> they need to update the typescript grammar, and the tsx grammar is 
> overwritten in the process too.

I don't see why that would be a problem.  The grammars that come in
pairs share common parts anyway, so I think updating them all is
actually slightly safer.