feat(nvim): add Rust LSP support

configs/nixos/modules/shell/nvim/config.lua

@@ -6,6 +6,31 @@ require("nord").setup({
 })
 vim.cmd.colorscheme("nord")
 
+-- Keep floating windows distinct from the current line highlight.
+vim.api.nvim_set_hl(0, "NormalFloat", { bg = "#2e3440" })
+vim.api.nvim_set_hl(0, "FloatBorder", { fg = "#88c0d0", bg = "#2e3440" })
+
+local open_floating_preview = vim.lsp.util.open_floating_preview
+vim.lsp.util.open_floating_preview = function(contents, syntax, opts, ...)
+  opts = opts or {}
+  opts.border = opts.border or "rounded"
+  return open_floating_preview(contents, syntax, opts, ...)
+end
+
+-- Format Rust buffers before writing them.
+vim.api.nvim_create_autocmd("BufWritePre", {
+  pattern = "*.rs",
+  callback = function(args)
+    vim.lsp.buf.format({
+      bufnr = args.buf,
+      timeout_ms = 2000,
+      filter = function(client)
+        return client.name == "rust_analyzer"
+      end,
+    })
+  end,
+})
+
 -- Conceal markdown syntax in markdown buffers.
 -- conceallevel is window-local, so it is set with opt_local when the filetype
 -- is applied to the buffer's window.

configs/nixos/modules/shell/nvim/default.nix

@@ -142,6 +142,54 @@ in
         ];
 
         plugins = {
+          blink-cmp = {
+            enable = true;
+            setupLspCapabilities = true;
+            settings = {
+              keymap = {
+                preset = "default";
+                "<M-Space>" = [
+                  "show"
+                  "show_documentation"
+                  "hide_documentation"
+                ];
+              };
+              completion.documentation.auto_show = true;
+              signature.enabled = true;
+              sources.default = [
+                "lsp"
+                "path"
+                "snippets"
+                "buffer"
+              ];
+            };
+          };
+
+          lsp = {
+            enable = true;
+            inlayHints = true;
+            keymaps = {
+              silent = true;
+              diagnostic = {
+                "[d" = "goto_prev";
+                "]d" = "goto_next";
+              };
+              lspBuf = {
+                gd = "definition";
+                gD = "references";
+                K = "hover";
+                "<leader>ca" = "code_action";
+                "<leader>rn" = "rename";
+              };
+            };
+            servers.rust_analyzer = lib.mkIf config.modules.shell.rust.enable {
+              enable = true;
+              installCargo = false;
+              installRustc = false;
+              installRustfmt = false;
+            };
+          };
+
           gitsigns = {
             enable = true;
             settings.current_line_blame = false;