plugins/nvim-lsp: add per-server onAttach option (#341)

plugins/_sources/generated.nix

@@ -1,5 +1,8 @@
 # This file was generated by nvfetcher, please do not modify it manually.
-{ fetchgit, fetchurl, fetchFromGitHub, dockerTools }:
 {
-  
+  fetchgit,
+  fetchurl,
+  fetchFromGitHub,
+  dockerTools,
+}: {
 }

plugins/nvim-lsp/helpers.nix

@@ -57,6 +57,24 @@
               `:LspStart` (|lspconfig-commands|).
             '';
 
+            onAttach =
+              helpers.mkCompositeOption "Server specific on_attach behavior."
+              {
+                override = mkOption {
+                  type = types.bool;
+                  default = false;
+                  description = "Override the global `plugins.lsp.onAttach` function.";
+                };
+
+                function = mkOption {
+                  type = types.str;
+                  description = ''
+                    Body of the on_attach function.
+                    The argument `client` and `bufnr` is provided.
+                  '';
+                };
+              };
+
             settings = settingsOptions;
 
             extraSettings = mkOption {
@@ -82,6 +100,16 @@
               name = serverName;
               extraOptions = {
                 inherit (cfg) cmd filetypes autostart;
+                on_attach =
+                  helpers.ifNonNull' cfg.onAttach
+                  (
+                    helpers.mkRaw ''
+                      function(client, bufnr)
+                        ${optionalString (!cfg.onAttach.override) config.plugins.lsp.onAttach}
+                        ${cfg.onAttach.function}
+                      end
+                    ''
+                  );
                 settings = (settings cfg.settings) // cfg.extraSettings;
               };
             }

tests/test-sources/plugins/nvim-lsp/nvim-lsp.nix

@@ -25,7 +25,12 @@
 
       servers = {
         bashls.enable = true;
-        clangd.enable = true;
+        clangd = {
+          enable = true;
+          onAttach.function = ''
+            print('The clangd language server has been attached !')
+          '';
+        };
         nil_ls.enable = true;
         rust-analyzer.enable = true;
         pylsp = {