languages/julia: add

Co-authored-by: raf <raf@notashelf.dev>

configuration.nix

@@ -65,17 +65,14 @@ isMaximal: {
       r.enable = isMaximal;
       tailwind.enable = isMaximal;
       typst.enable = isMaximal;
-      clang = {
+      clang.enable = isMaximal;
-        enable = isMaximal;
-        lsp.server = "clangd";
-      };
-
       scala.enable = isMaximal;
       rust = {
         enable = isMaximal;
         crates.enable = isMaximal;
       };
       csharp.enable = isMaximal;
+      julia.enable = isMaximal;
     };
 
     visuals = {

docs/release-notes/rl-0.7.md

@@ -192,6 +192,10 @@ To migrate to `nixfmt`, simply change `vim.languages.nix.format.type` to
 - Add C# support under `vim.languages.csharp`, with support for both
   omnisharp-roslyn and csharp-language-server.
 
+- Add Julia support under `vim.languages.julia`. Note that the entirety of Julia
+  is bundled with nvf, if you enable the module, since there is no way to
+  provide only the LSP server.
+
 [Neovim documentation on `vim.cmd`]: https://neovim.io/doc/user/lua.html#vim.cmd()
 
 - Make Neovim's configuration file entirely Lua based. This comes with a few

modules/plugins/languages/default.nix

@@ -29,6 +29,7 @@ in {
     ./typst.nix
     ./zig.nix
     ./csharp.nix
+    ./julia.nix
   ];
 
   options.vim.languages = {

modules/plugins/languages/julia.nix

@@ -0,0 +1,126 @@
+{
+  lib,
+  pkgs,
+  config,
+  ...
+}: let
+  inherit (builtins) attrNames isList;
+  inherit (lib.options) mkEnableOption mkOption;
+  inherit (lib.types) either listOf package str enum bool nullOr;
+  inherit (lib.modules) mkIf mkMerge;
+  inherit (lib.strings) optionalString;
+  inherit (lib.nvim.types) mkGrammarOption;
+  inherit (lib.nvim.lua) expToLua;
+
+  defaultServer = "julials";
+  servers = {
+    julials = {
+      package = pkgs.julia.withPackages ["LanguageServer"];
+      internalFormatter = true;
+      lspConfig = ''
+        lspconfig.julials.setup {
+          capabilities = capabilities,
+          on_attach = default_on_attach,
+          cmd = ${
+          if isList cfg.lsp.package
+          then expToLua cfg.lsp.package
+          else ''
+            {
+              "${optionalString (cfg.lsp.package != null) "${cfg.lsp.package}/bin/"}julia",
+              "--startup-file=no",
+              "--history-file=no",
+              "--eval",
+              [[
+                using LanguageServer
+
+                depot_path = get(ENV, "JULIA_DEPOT_PATH", "")
+                project_path = let
+                    dirname(something(
+                        ## 1. Finds an explicitly set project (JULIA_PROJECT)
+                        Base.load_path_expand((
+                            p = get(ENV, "JULIA_PROJECT", nothing);
+                            p === nothing ? nothing : isempty(p) ? nothing : p
+                        )),
+                        ## 2. Look for a Project.toml file in the current working directory,
+                        ##    or parent directories, with $HOME as an upper boundary
+                        Base.current_project(),
+                        ## 3. First entry in the load path
+                        get(Base.load_path(), 1, nothing),
+                        ## 4. Fallback to default global environment,
+                        ##    this is more or less unreachable
+                        Base.load_path_expand("@v#.#"),
+                    ))
+                end
+                @info "Running language server" VERSION pwd() project_path depot_path
+                server = LanguageServer.LanguageServerInstance(stdin, stdout, project_path, depot_path)
+                server.runlinter = true
+                run(server)
+              ]]
+            }
+          ''
+        }
+        }
+      '';
+    };
+  };
+
+  cfg = config.vim.languages.julia;
+in {
+  options = {
+    vim.languages.julia = {
+      enable = mkEnableOption "Julia language support";
+
+      treesitter = {
+        enable = mkEnableOption "Julia treesitter" // {default = config.vim.languages.enableTreesitter;};
+        package = mkGrammarOption pkgs "julia";
+      };
+
+      lsp = {
+        enable = mkOption {
+          type = bool;
+          default = config.vim.languages.enableLSP;
+          description = ''
+            Whether to enable Julia LSP support.
+
+            ::: {.note}
+            The entirety of Julia is bundled with nvf, if you enable this
+            option, since there is no way to provide only the LSP server.
+
+            If you want to avoid that, you have to change
+            [](#opt-vim.languages.julia.lsp.package) to use the Julia binary
+            in {env}`PATH` (set it to `null`), and add the `LanguageServer` package to
+            Julia in your devshells.
+            :::
+          '';
+        };
+
+        server = mkOption {
+          type = enum (attrNames servers);
+          default = defaultServer;
+          description = "Julia LSP server to use";
+        };
+
+        package = mkOption {
+          description = ''
+            Julia LSP server package, `null` to use the Julia binary in {env}`PATH`, or
+            the command to run as a list of strings.
+          '';
+          type = nullOr (either package (listOf str));
+          default = servers.${cfg.lsp.server}.package;
+        };
+      };
+    };
+  };
+
+  config = mkIf cfg.enable (mkMerge [
+    (mkIf cfg.treesitter.enable {
+      vim.treesitter.enable = true;
+      vim.treesitter.grammars = [cfg.treesitter.package];
+    })
+
+    (mkIf cfg.lsp.enable {
+      vim.lsp.lspconfig.enable = true;
+      vim.lsp.lspconfig.sources.julia-lsp = servers.${cfg.lsp.server}.lspConfig;
+    })
+  ]);
+}