From 3c661562f42ad87e1aefaad163c2df6d14ab5a32 Mon Sep 17 00:00:00 2001
From: Mora Unie Youer <mora_unie_youer@riseup.net>
Date: Sun, 30 Mar 2025 13:58:24 +0300
Subject: feat: add `rust-analyzer` as Rust LSP

---
 flake.nix                         |  8 ++++++++
 lsp/rust-analyzer.lua             | 26 ++++++++++++++++++++++++++
 lua/config/lsp.lua                |  1 +
 lua/config/plugins/formatting.lua |  1 +
 4 files changed, 36 insertions(+)
 create mode 100644 lsp/rust-analyzer.lua

diff --git a/flake.nix b/flake.nix
index a919ace..207a8a1 100644
--- a/flake.nix
+++ b/flake.nix
@@ -129,11 +129,19 @@
                 lua-language-server
                 stylua
               ];
+
               nix = [
                 nix-doc
                 nixd
                 nixfmt-rfc-style
               ];
+
+              rust = [
+                # NOTE: required to find project root
+                # NOTE: for now unused, so commented out
+                # cargo
+                rust-analyzer
+              ];
             };
           };
 
diff --git a/lsp/rust-analyzer.lua b/lsp/rust-analyzer.lua
new file mode 100644
index 0000000..51f5037
--- /dev/null
+++ b/lsp/rust-analyzer.lua
@@ -0,0 +1,26 @@
+return {
+	cmd = { "rust-analyzer" },
+	root_markers = { "Cargo.toml" },
+	filetypes = { "rust" },
+
+	settings = {
+		["rust-analyzer"] = {
+			checkOnSave = { command = "clippy" },
+
+			diagnostics = {
+				enable = true,
+				experimental = { enable = true },
+			},
+
+			inlayHints = {
+				enable = true,
+				bindingModeHints = { enable = false },
+				closingBraceHints = { minLines = 10 },
+				closureReturnTypeHints = { enable = "with_block" },
+				discriminantHints = { enable = "fieldless" },
+				lifetimeElisionHints = { enable = "skip_trivial" },
+				typeHints = { hideClosureInitialization = false },
+			},
+		},
+	},
+}
diff --git a/lua/config/lsp.lua b/lua/config/lsp.lua
index 37e3b6f..6d4a680 100644
--- a/lua/config/lsp.lua
+++ b/lua/config/lsp.lua
@@ -1,2 +1,3 @@
 vim.lsp.enable("lua-language-server")
 vim.lsp.enable("nixd")
+vim.lsp.enable("rust-analyzer")
diff --git a/lua/config/plugins/formatting.lua b/lua/config/plugins/formatting.lua
index 8a4c6ab..9563905 100644
--- a/lua/config/plugins/formatting.lua
+++ b/lua/config/plugins/formatting.lua
@@ -9,6 +9,7 @@ return {
 				formatters_by_ft = {
 					lua = { "stylua" },
 					nix = { "nixfmt" },
+					rust = { "rustfmt", lsp_format = "fallback" },
 				},
 			})
 
-- 
cgit v1.2.3-70-g09d2