From bb3721e92d99ceee023614cedab78b85a2048b9c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ga=C3=A9tan=20Lepage?=
 <33058747+GaetanLepage@users.noreply.github.com>
Date: Mon, 20 Feb 2023 17:32:05 +0100
Subject: [PATCH] nvim-lsp: added nvim-cmp completion capabilities (#158)

Co-authored-by: Pedro Alves <pta2002@pta2002.com>
---
 plugins/completion/nvim-cmp/default.nix | 10 +++++++++-
 plugins/default.nix                     |  1 +
 plugins/nvim-lsp/default.nix            | 17 ++++++++++++++++-
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/plugins/completion/nvim-cmp/default.nix b/plugins/completion/nvim-cmp/default.nix
index 7c362c16..1e978763 100644
--- a/plugins/completion/nvim-cmp/default.nix
+++ b/plugins/completion/nvim-cmp/default.nix
@@ -453,6 +453,14 @@ in {
           })
           known_source_names);
       in
-        mkIf cfg.auto_enable_sources attrs_enabled;
+        mkMerge [
+          (mkIf cfg.auto_enable_sources attrs_enabled)
+          (mkIf (elem "nvim_lsp" found_sources)
+            {
+              lsp.capabilities = ''
+                capabilities = require('cmp_nvim_lsp').default_capabilities()
+              '';
+            })
+        ];
     };
 }
diff --git a/plugins/default.nix b/plugins/default.nix
index 9a605827..140c5a1c 100644
--- a/plugins/default.nix
+++ b/plugins/default.nix
@@ -21,6 +21,7 @@
     ./git/gitmessenger.nix
     ./git/gitsigns.nix
     ./git/neogit.nix
+
     ./languages/clangd-extensions.nix
     ./languages/ledger.nix
     ./languages/markdown-preview.nix
diff --git a/plugins/nvim-lsp/default.nix b/plugins/nvim-lsp/default.nix
index 66dcdb23..c621d9e7 100644
--- a/plugins/nvim-lsp/default.nix
+++ b/plugins/nvim-lsp/default.nix
@@ -44,6 +44,12 @@ in {
         default = "";
       };
 
+      capabilities = mkOption {
+        type = types.lines;
+        description = "Lua code that modifies inplace the `capabilities` table.";
+        default = "";
+      };
+
       setupWrappers = mkOption {
         type = with types; listOf (functionTo str);
         description = "Code to be run to wrap the setup args. Takes in an argument containing the previous results, and returns a new string of code.";
@@ -78,13 +84,22 @@ in {
         -- LSP {{{
         do
           ${cfg.preConfig}
+
           local __lspServers = ${helpers.toLuaObject cfg.enabledServers}
           local __lspOnAttach = function(client, bufnr)
             ${cfg.onAttach}
           end
+          local __lspCapabilities = function()
+            capabilities = vim.lsp.protocol.make_client_capabilities()
+
+            ${cfg.capabilities}
+
+            return capabilities
+          end
 
           local __setup = ${runWrappers cfg.setupWrappers "{
-            on_attach = __lspOnAttach
+            on_attach = __lspOnAttach,
+            capabilities = __lspCapabilities()
           }"}
 
           for i,server in ipairs(__lspServers) do