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

[Dmitry Gutov <dmitry@gutov.dev>]

On 20/06/2024 18:59, Eli Zaretskii wrote:
>> 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.

It will work only in the case where Bob specifies 'typescript', not 'tsx'.

>>>> 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?

See the previous mentioned problems with it.

>> 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.

That might be true, though probably not in all cases.

Our major modes for typescript and tsx do share some parts of the 
definition.