cmake: install M2-language-server script

[d-torrance]

I just installed M2 on my new MacBook and noticed that the language server script was missing!

The homebrew package uses the cmake build, and (as usual), I don't really understand cmake that well and didn't realize we needed an additional install() . I figured that just copying it to usr-dist like we do for the autotools build was sufficient. Nope!

AI Disclosure

Claude figured out what was missing and added the fix.

[mahrud]

Oh, I hadn't seen the this script. Aside from cmake conventions, I don't think this script is the right way to go because it doesn't work if M2 isn't on the path or if you have multiple M2's on different paths, e.g. if I'm running M2 from a build directory I might not want the M2-language-server from brew to be used.

I would suggest one two options:

1. move this script to the Macaulay2/bin directory and adjust it like the M2 script to run the correct M2-binary or just call ./M2 in the same directory, then move the install call to bin/CMakeFiles.txt and remove the COPY call.
2. better yet, add this invocation as an argument to M2, e.g. startup.m2 should parse --LSP and just run this, with no extra files involved.

[d-torrance]

Ooh, yeah, I like option 1. I'm hesitant about option 2. In particular, I foresee adding command-line options to M2-language-server soon and I'd rather not conflate them with M2's command-line options.

[mahrud]

You could have a phase 0 check that if --LSP is present, option processing should stop and pass on to your script instead, similar to --silent which must be used like M2 --script blah.m2.

[d-torrance]

I updated the script to check first for the existence of a "sibling" M2 in the same directory and then if it can't find one, fall back to just calling M2.

I decided to keep everything in the packages directory rather than bin to not spread things out too much and keep bin devoted to just the Macaulay2 binary.

[mahrud]

I would like the lines added to packages/CMakeFiles.txt in the previous PR to be removed. Further, since humans would not need to run M2-language-server directly, I don't want it to be on the path. For instance, I use M2- with different postfixes for different versions of M2 compiled on different branches and adding it to path unnecessarily pollutes autocompletion.

You can make this a separate debian package / brew formula which can be selectively installed.

[d-torrance]

I thought I removed the stray newline?

I don't understand why this shouldn't be on the PATH. Even if humans won't run it directly, editors certainly will.

[mahrud]

These lines should not be here. This file is for packages only.

I still think adding --language-server option in startup.m2 is the best option, but another alternative is adding a target under Macaulay2/editors/language-server. e.g. prism and generate-symbols.m2 interact with the Style package, but we don't write those targets in packages/CMakeFiles.txt just because Style is in this directory.

[d-torrance]

But the language server is a package... It's an unusual package in that it has an accompanying script and folks would rarely if ever ever load it by hand, but all the related code is here in the packages directory.

I'd rather avoid touching startup.m2. Keeping the script in the package's auxiliary directory keeps everything close together, and also doesn't require recompiling M2.

I think the comparison to prism actually supports the current proprosal. For prism, the build system targets live in the editors directory since that's where the source code is even though the files get installed alongside the packages. Same idea here -- the source code is in packages but we're installing it alongside the binary.

[mahrud]

For prism, the build system targets live in the editors directory since that's where the source code is even though the files get installed alongside the packages.

The template is there but the file is generated by generateSymbols which lives in the Style package, so these two seem contradictory:

• we should keep the script in the package's aux directory to keep things together
• we should keep the script in the directory where it gets installed

Either move it to Macaulay2/bin if it needs to be installed on path next to M2 and M2-binary (the main file could live in bin and have a symlink from the aux directory), or to Macaulay2/editors/language-server and put the path in editor configuration.

[mahrud]

I don't understand why this shouldn't be on the PATH. Even if humans won't run it directly, editors certainly will.

I believe libexec/Macaulay2/bin is meant for this purpose.

[d-torrance]

I don't understand why this shouldn't be on the PATH. Even if humans won't run it directly, editors certainly will.

I believe libexec/Macaulay2/bin is meant for this purpose.

That's where binaries that M2 would call should live. A language server should be on PATH so an arbitrary editor can run it.