bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Misha Zharov]

Add (sql "https://github.com/m-novikov/tree-sitter-sql") to
treesit-language-source-alist. Then use
treesit-install-language-grammar. The following error occurs:

    Error encountered when installing language grammar: (treesit-error
    Command: cc -fPIC -c -I. parser.c Error output: cc1: fatal error:
    parser.c: No such file or directory compilation terminated.)

This error occurs because we need to run a configuration step on the
repo to generate parser.c. I believe this is because we need to either
run `npm run generate` or `tree-sitter generate` to generate the
`src/parser.c` file. It would be nice if we could implement a patch to:

  1. Allow users to specify a configuration step to configure the repo
     before searching for parser.c (like passing a lambda into
     `treesit-language-source-alist`)
  2. Allow users to specify a git hash that should be checked out before
     the configuration step is run. I know currently different branches
     are supported, but not all projects have release branches.
  3. Alternatively this function can be split into 2 function, the first one
      would clone and configure the repository, and well as find the
      required files. The second function would simply compile the required
      files into the shared libraries, and move them to the appropriate location

I can have a go at implementing some of the above if those changes are
welcome. The reason this is important is because it seems like more
repos in the future will move away from providing the autogenerated
files in their repos, so this function might be on borrowed time in its
current incarnation.


In GNU Emacs 29.0.60 (build 1, x86_64-pc-linux-gnu, GTK+ Version
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bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> From: Misha Zharov <mishazharov1@gmail.com>
> Date: Sun, 26 Feb 2023 23:34:57 -0800
> 
> Add (sql "https://github.com/m-novikov/tree-sitter-sql") to
> treesit-language-source-alist. Then use
> treesit-install-language-grammar. The following error occurs:
> 
>     Error encountered when installing language grammar: (treesit-error
>     Command: cc -fPIC -c -I. parser.c Error output: cc1: fatal error:
>     parser.c: No such file or directory compilation terminated.)
> 
> This error occurs because we need to run a configuration step on the
> repo to generate parser.c. I believe this is because we need to either
> run `npm run generate` or `tree-sitter generate` to generate the
> `src/parser.c` file. It would be nice if we could implement a patch to:
> 
>   1. Allow users to specify a configuration step to configure the repo
>      before searching for parser.c (like passing a lambda into
>      `treesit-language-source-alist`)
>   2. Allow users to specify a git hash that should be checked out before
>      the configuration step is run. I know currently different branches
>      are supported, but not all projects have release branches.
>   3. Alternatively this function can be split into 2 function, the first one
>       would clone and configure the repository, and well as find the
>       required files. The second function would simply compile the required
>       files into the shared libraries, and move them to the appropriate location

I'm not sure we should incorporate in Emacs so much of this
specialized stuff.  treesit-install-language-grammar is meant for
doing the simple steps of compiling C/C++ sources in a boilerplate
repository into a shared library.  Anything significantly more complex
should IMO be left to manual procedures by people who know what they
are doing, especially if that requires to have specialized tools
installed.

(Btw, why not use https://github.com/DerekStride/tree-sitter-sql
instead?)

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Misha Zharov]

Thanks for getting back to me

> (Btw, why not use https://github.com/DerekStride/tree-sitter-sql
> instead?)

I just landed on the other one first, no particular reason.  Initially it
worked until they removed the autogenerated code that was in
the repo.  As a workaround I can switch to the sql grammar that you
have recommended, but the problem might occur again in other
repos.

> I'm not sure we should incorporate in Emacs so much of this
> specialized stuff.

That's fair, but I fear that more repos will remove the autogenerated
parser code, which will make treesit-install-language-grammar
much less useful.  Perhaps this won't occur often, but I wanted to
consult on a possible solution.  However, since this appears to be
working as intended, then that is okay as well.

Thanks for taking the time to look into this.

On Mon, Feb 27, 2023 at 12:00 PM Eli Zaretskii <eliz@gnu.org> wrote:
>
> > From: Misha Zharov <mishazharov1@gmail.com>
> > Date: Sun, 26 Feb 2023 23:34:57 -0800
> >
> > Add (sql "https://github.com/m-novikov/tree-sitter-sql") to
> > treesit-language-source-alist. Then use
> > treesit-install-language-grammar. The following error occurs:
> >
> >     Error encountered when installing language grammar: (treesit-error
> >     Command: cc -fPIC -c -I. parser.c Error output: cc1: fatal error:
> >     parser.c: No such file or directory compilation terminated.)
> >
> > This error occurs because we need to run a configuration step on the
> > repo to generate parser.c. I believe this is because we need to either
> > run `npm run generate` or `tree-sitter generate` to generate the
> > `src/parser.c` file. It would be nice if we could implement a patch to:
> >
> >   1. Allow users to specify a configuration step to configure the repo
> >      before searching for parser.c (like passing a lambda into
> >      `treesit-language-source-alist`)
> >   2. Allow users to specify a git hash that should be checked out before
> >      the configuration step is run. I know currently different branches
> >      are supported, but not all projects have release branches.
> >   3. Alternatively this function can be split into 2 function, the first one
> >       would clone and configure the repository, and well as find the
> >       required files. The second function would simply compile the required
> >       files into the shared libraries, and move them to the appropriate location
>
> I'm not sure we should incorporate in Emacs so much of this
> specialized stuff.  treesit-install-language-grammar is meant for
> doing the simple steps of compiling C/C++ sources in a boilerplate
> repository into a shared library.  Anything significantly more complex
> should IMO be left to manual procedures by people who know what they
> are doing, especially if that requires to have specialized tools
> installed.
>
> (Btw, why not use https://github.com/DerekStride/tree-sitter-sql
> instead?)

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> From: Misha Zharov <mishazharov1@gmail.com>
> Date: Mon, 27 Feb 2023 19:13:59 -0800
> Cc: 61849@debbugs.gnu.org
> 
> Thanks for getting back to me
> 
> > (Btw, why not use https://github.com/DerekStride/tree-sitter-sql
> > instead?)
> 
> I just landed on the other one first, no particular reason.  Initially it
> worked until they removed the autogenerated code that was in
> the repo.  As a workaround I can switch to the sql grammar that you
> have recommended, but the problem might occur again in other
> repos.
> 
> > I'm not sure we should incorporate in Emacs so much of this
> > specialized stuff.
> 
> That's fair, but I fear that more repos will remove the autogenerated
> parser code, which will make treesit-install-language-grammar
> much less useful.

If that starts to happen too much, we'll need to rethink this feature.
It is supposed to be extremely reliable, and this should not rely on
tools that might not be installed, because giving clueless users a
tool that fails unless one "tinkers" is not a good idea, IMO.

I'll leave this bug open for now.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Yuan Fu]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Misha Zharov <mishazharov1@gmail.com>
>> Date: Mon, 27 Feb 2023 19:13:59 -0800
>> Cc: 61849@debbugs.gnu.org
>> 
>> Thanks for getting back to me
>> 
>> > (Btw, why not use https://github.com/DerekStride/tree-sitter-sql
>> > instead?)
>> 
>> I just landed on the other one first, no particular reason.  Initially it
>> worked until they removed the autogenerated code that was in
>> the repo.  As a workaround I can switch to the sql grammar that you
>> have recommended, but the problem might occur again in other
>> repos.
>> 
>> > I'm not sure we should incorporate in Emacs so much of this
>> > specialized stuff.
>> 
>> That's fair, but I fear that more repos will remove the autogenerated
>> parser code, which will make treesit-install-language-grammar
>> much less useful.
>
> If that starts to happen too much, we'll need to rethink this feature.
> It is supposed to be extremely reliable, and this should not rely on
> tools that might not be installed, because giving clueless users a
> tool that fails unless one "tinkers" is not a good idea, IMO.
>
> I'll leave this bug open for now.

Not sure why that project removed the grammar.c files, it seems
ubiquitous for tree-sitter language grammar projects to include the
generated grammar.c file in the repo.

Yuan

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Fri, 3 Mar 2023 14:27:05 -0800
> Cc: mishazharov1@gmail.com,
>  61849@debbugs.gnu.org
> 
> Not sure why that project removed the grammar.c files, it seems
> ubiquitous for tree-sitter language grammar projects to include the
> generated grammar.c file in the repo.

Maybe we should file an issue in their issue tracker, asking them to
bring that file back.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> Cc: mishazharov1@gmail.com, 61849@debbugs.gnu.org
> Date: Sat, 04 Mar 2023 09:06:37 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> 
> > From: Yuan Fu <casouri@gmail.com>
> > Date: Fri, 3 Mar 2023 14:27:05 -0800
> > Cc: mishazharov1@gmail.com,
> >  61849@debbugs.gnu.org
> > 
> > Not sure why that project removed the grammar.c files, it seems
> > ubiquitous for tree-sitter language grammar projects to include the
> > generated grammar.c file in the repo.
> 
> Maybe we should file an issue in their issue tracker, asking them to
> bring that file back.

Now done, see https://github.com/m-novikov/tree-sitter-sql/issues/72

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Misha Zharov]

> Now done, see https://github.com/m-novikov/tree-sitter-sql/issues/72

Great, thanks for following up and filing the ticket.  I subscribed to
it and will watch it for any further developments

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> Cc: 61849@debbugs.gnu.org
> Date: Sat, 04 Mar 2023 13:06:50 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> 
> > Cc: mishazharov1@gmail.com, 61849@debbugs.gnu.org
> > Date: Sat, 04 Mar 2023 09:06:37 +0200
> > From: Eli Zaretskii <eliz@gnu.org>
> > 
> > > From: Yuan Fu <casouri@gmail.com>
> > > Date: Fri, 3 Mar 2023 14:27:05 -0800
> > > Cc: mishazharov1@gmail.com,
> > >  61849@debbugs.gnu.org
> > > 
> > > Not sure why that project removed the grammar.c files, it seems
> > > ubiquitous for tree-sitter language grammar projects to include the
> > > generated grammar.c file in the repo.
> > 
> > Maybe we should file an issue in their issue tracker, asking them to
> > bring that file back.
> 
> Now done, see https://github.com/m-novikov/tree-sitter-sql/issues/72

The other grammar for SQL followed suit, unfortunately, see

  https://github.com/DerekStride/tree-sitter-sql/issues/120

Please chime in to try to convince them to go back to including the
generated parser files.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Misha Zharov]

> Please chime in to try to convince them to go back to including the
> generated parser files.

Thanks for the update.  I've now done this, but I think that it will be
difficult to make sure that community sticks to this standard of keeping
the autogenerated files in the repo.  Their arguments do have some
merit regarding the difficulty of resolving merge conflicts and overall
maintenance burden.  At the same time, having the autogenerated file
present is a nice QOL feature for users because it's easily reproducible.

I'm not sure what the ultimate solution to this will be though.  It might be
necessary to come up with a new paradigm of installing treesitter
grammars that addresses some of the current issues

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> From: Misha Zharov <mishazharov1@gmail.com>
> Date: Sun, 19 Mar 2023 22:14:44 -0700
> Cc: casouri@gmail.com, 61849@debbugs.gnu.org
> 
> > Please chime in to try to convince them to go back to including the
> > generated parser files.
> 
> Thanks for the update.  I've now done this, but I think that it will be
> difficult to make sure that community sticks to this standard of keeping
> the autogenerated files in the repo.  Their arguments do have some
> merit regarding the difficulty of resolving merge conflicts and overall
> maintenance burden.  At the same time, having the autogenerated file
> present is a nice QOL feature for users because it's easily reproducible.

Bummer:

  https://github.com/DerekStride/tree-sitter-sql/issues/120#issuecomment-1476609242

> I'm not sure what the ultimate solution to this will be though.  It might be
> necessary to come up with a new paradigm of installing treesitter
> grammars that addresses some of the current issues

Maybe.  better yet, the various distros should hopefully pick up the
gauntlet and startr providing prebuilt binaries of these grammar
libraries for users to install using standard tools.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Dmitry Gutov]

On 20/03/2023 21:28, Eli Zaretskii wrote:
>> From: Misha Zharov<mishazharov1@gmail.com>
>> Date: Sun, 19 Mar 2023 22:14:44 -0700
>> Cc:casouri@gmail.com,61849@debbugs.gnu.org
>>
>>> Please chime in to try to convince them to go back to including the
>>> generated parser files.
>> Thanks for the update.  I've now done this, but I think that it will be
>> difficult to make sure that community sticks to this standard of keeping
>> the autogenerated files in the repo.  Their arguments do have some
>> merit regarding the difficulty of resolving merge conflicts and overall
>> maintenance burden.  At the same time, having the autogenerated file
>> present is a nice QOL feature for users because it's easily reproducible.
> Bummer:
> 
>    https://github.com/DerekStride/tree-sitter-sql/issues/120#issuecomment-1476609242

Suppose the repositories remove the generated grammar files. What would 
be sufficient for us to regenerate them?

tree-sitter-sql apparently uses the tree-sitter-cli program. Would 
having it on the user's system suffice?

For a lot of developers NPM will already be installed. If the only 
remaining step will be 'npm install -g tree-sitter-cli', or dropping one 
of the pre-built binaries from 
https://github.com/tree-sitter/tree-sitter/releases into a directory on 
PATH, I think they could manage to do it once, to be used in all 
grammars which don't keep generated files in the repo.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> Date: Mon, 20 Mar 2023 22:04:41 +0200
> Cc: casouri@gmail.com, 61849@debbugs.gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> 
> Suppose the repositories remove the generated grammar files. What would 
> be sufficient for us to regenerate them?

I hope someone will write a generation tool in Emacs Lisp.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Gregory Heytings]

>> Suppose the repositories remove the generated grammar files. What would 
>> be sufficient for us to regenerate them?
>
> I hope someone will write a generation tool in Emacs Lisp.
>

That can't possibly happen, IMO.  Generating the grammar.json files from 
the grammar.js files with an Emacs Lisp program would amount to implement 
a JavaScript interpreter in Emacs Lisp.  And generating the parser.c files 
from the grammar.json files would amount to reimplement the generator, 
which is about 13500 lines of non-trivial Rust code, in Emacs Lisp.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Eli Zaretskii]

> Date: Mon, 20 Mar 2023 22:01:15 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: Dmitry Gutov <dgutov@yandex.ru>, mishazharov1@gmail.com, casouri@gmail.com, 
>     61849@debbugs.gnu.org
> 
> 
> >> Suppose the repositories remove the generated grammar files. What would 
> >> be sufficient for us to regenerate them?
> >
> > I hope someone will write a generation tool in Emacs Lisp.
> >
> 
> That can't possibly happen, IMO.  Generating the grammar.json files from 
> the grammar.js files with an Emacs Lisp program would amount to implement 
> a JavaScript interpreter in Emacs Lisp.

So you are saying that generating a parser would need a JavaScript
interpreter as part of the generation?  Does tree-sitter-cli tool
invoke it, then (I didn't study its sources)?

> And generating the parser.c files from the grammar.json files would
> amount to reimplement the generator, which is about 13500 lines of
> non-trivial Rust code, in Emacs Lisp.

That's what I hoped someone will do, yes.  It's a non-trivial job, but
surely isn't impossible.  Reimplementing that in some other widely
available language, like Python or Perl, would also do.  Or maybe the
Rust front-end to GCC will become available soon enough.  Or something.

bug#61849: 29.0.60; Unable to use treesit-install-language-grammar because repo doesn't have parser.c

[Gregory Heytings]

>> Generating the grammar.json files from the grammar.js files with an 
>> Emacs Lisp program would amount to implement a JavaScript interpreter 
>> in Emacs Lisp.
>
> So you are saying that generating a parser would need a JavaScript 
> interpreter as part of the generation?
>

Yes.

>
> Does tree-sitter-cli tool invoke it, then (I didn't study its sources)?
>

Yes, here: https://github.com/tree-sitter/tree-sitter/blob/master/cli/src/generate/mod.rs#L169.

>> And generating the parser.c files from the grammar.json files would 
>> amount to reimplement the generator, which is about 13500 lines of 
>> non-trivial Rust code, in Emacs Lisp.
>
> That's what I hoped someone will do, yes.  It's a non-trivial job, but 
> surely isn't impossible.  Reimplementing that in some other widely 
> available language, like Python or Perl, would also do.  Or maybe the 
> Rust front-end to GCC will become available soon enough.  Or something.
>

It's not impossible, but what would be the benefit (and/or incentive) of 
doing that?  Rust is already widely available, under a liberal licence, 
and it is also not necessary to create the parser.c file, which is 
architecture-independent, on the computer on which it is compiled.  Also 
note that generating the parser.c file can use _a lot_ of resources, e.g. 
generating the parser.c file of tree-sitter-c-sharp from the grammar.json 
file uses 40 (fourty!) GB of memory and takes several minutes.  I'll let 
you imagine what these numbers would be with an interpreted language like 
Elisp, Python or Perl.