From 16753bfc5205a11d2e1bc29aee5ba570571845e7 Mon Sep 17 00:00:00 2001
From: Snoweuph <snow@euph.email>
Date: Sat, 11 Apr 2026 18:03:08 +0200
Subject: [PATCH] lsp/presets/ocaml-lsp: init

---
 modules/plugins/lsp/presets/default.nix   |  1 +
 modules/plugins/lsp/presets/ocaml-lsp.nix | 44 +++++++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 modules/plugins/lsp/presets/ocaml-lsp.nix

diff --git a/modules/plugins/lsp/presets/default.nix b/modules/plugins/lsp/presets/default.nix
index 1a497b49..714c39b5 100644
--- a/modules/plugins/lsp/presets/default.nix
+++ b/modules/plugins/lsp/presets/default.nix
@@ -5,6 +5,7 @@
     ./harper.nix
     ./intelephense.nix
     ./lemminx.nix
+    ./ocaml-lsp.nix
     ./ols.nix
     ./openscad-lsp.nix
     ./phan.nix
diff --git a/modules/plugins/lsp/presets/ocaml-lsp.nix b/modules/plugins/lsp/presets/ocaml-lsp.nix
new file mode 100644
index 00000000..0e9b0952
--- /dev/null
+++ b/modules/plugins/lsp/presets/ocaml-lsp.nix
@@ -0,0 +1,44 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}: let
+  inherit (lib.meta) getExe;
+  inherit (lib.modules) mkIf;
+  inherit (lib.options) mkEnableOption;
+  inherit (lib.generators) mkLuaInline;
+
+  cfg = config.vim.lsp.presets.ocaml-lsp;
+in {
+  options.vim.lsp.presets.ocaml-lsp = {
+    enable = mkEnableOption "the OCaml Language Server";
+  };
+
+  config = mkIf cfg.enable {
+    vim.lsp.servers.ocaml-lsp = {
+      enable = true;
+      cmd = [(getExe pkgs.ocamlPackages.ocaml-lsp)];
+      root_dir = mkLuaInline ''
+        function(bufnr, on_dir)
+          local fname = vim.api.nvim_buf_get_name(bufnr)
+          on_dir(util.root_pattern('*.opam', 'esy.json', 'package.json', '.git', 'dune-project', 'dune-workspace')(fname))
+        end
+      '';
+      get_language_id = mkLuaInline ''
+        function(_, ftype)
+          local language_id_of = {
+            menhir = 'ocaml.menhir',
+            ocaml = 'ocaml',
+            ocamlinterface = 'ocaml.interface',
+            ocamllex = 'ocaml.ocamllex',
+            reason = 'reason',
+            dune = 'dune',
+          }
+
+          return language_id_of[ftype]
+        end
+      '';
+    };
+  };
+}