plugins/rust-tools: Add a plugins for LSP extensions for rust-analyzer (#132)

plugins/default.nix

@@ -24,6 +24,7 @@
     ./languages/ledger.nix
     ./languages/nix.nix
     ./languages/plantuml-syntax.nix
+    ./languages/rust.nix
     ./languages/treesitter.nix
     ./languages/treesitter-context.nix
     ./languages/treesitter-refactor.nix

plugins/languages/rust.nix

@@ -0,0 +1,218 @@
+{
+  pkgs,
+  config,
+  lib,
+  helpers,
+  ...
+}:
+with lib; {
+  options.plugins.rust-tools = let
+    mkNullableOptionWithDefault = {
+      type,
+      description,
+      default,
+    }:
+      mkOption {
+        type = types.nullOr type;
+        default = null;
+        description = ''
+          ${description}
+
+          default: `${default}`
+        '';
+      };
+
+    mkNullableBoolDefault = default: description:
+      mkNullableOptionWithDefault {
+        inherit description;
+        type = types.bool;
+        default = toString default;
+      };
+
+    mkNullableStrDefault = default: description:
+      mkNullableOptionWithDefault {
+        inherit description;
+        type = types.str;
+        default = ''"${default}"'';
+      };
+
+    mkNullableIntDefault = default: description:
+      mkNullableOptionWithDefault {
+        inherit description;
+        type = types.int;
+        default = toString default;
+      };
+  in {
+    enable = mkEnableOption "Enable rust tools plugins";
+    package = mkOption {
+      type = types.package;
+      default = pkgs.vimPlugins.rust-tools-nvim;
+      description = "Package to use for rust-tools";
+    };
+
+    executor = mkNullableOptionWithDefault {
+      type = types.enum ["termopen" "quickfix"];
+      default = ''"termopen"'';
+      description = "how to execute terminal commands";
+    };
+
+    onIntialized = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      description = ''
+        Callback to execute once rust-analyzer is done initializing the workspace
+        The callback receives one parameter indicating the `health` of the server:
+        "ok" | "warning" | "error"
+      '';
+    };
+
+    reloadWorkspaceFromCargoToml = mkNullableBoolDefault true ''
+      Automatically call RustReloadWorkspace when writing to a Cargo.toml file.
+    '';
+
+    inlayHints = {
+      auto = mkNullableBoolDefault true "automatically set inlay hints (type hints)";
+
+      onlyCurrentLine = mkNullableBoolDefault false "Only show for current line";
+
+      showParameterHints =
+        mkNullableBoolDefault true
+        "whether to show parameter hints with the inlay hints or not";
+
+      parameterHintsPrefix = mkNullableStrDefault "<- " "prefix for parameter hints";
+      otherHintsPrefix = mkNullableStrDefault "=> " "prefix for all the other hints (type, chaining)";
+
+      maxLenAlign =
+        mkNullableBoolDefault false
+        "whether to align to the length of the longest line in the file";
+
+      maxLenAlignPadding = mkNullableIntDefault 1 "padding from the left if max_len_align is true";
+
+      rightAlign = mkNullableBoolDefault false "whether to align to the extreme right or not";
+      rightAlignPadding = mkNullableIntDefault 7 "padding from the right if right_align is true";
+
+      highlight = mkNullableStrDefault "Comment" "The color of the hints";
+    };
+
+    hoverActions = {
+      border = mkOption {
+        type = types.nullOr types.anything;
+        default = null;
+        description = ''
+          the border that is used for the hover window. see vim.api.nvim_open_win()
+        '';
+      };
+
+      maxWidth = mkOption {
+        type = types.nullOr types.int;
+        default = null;
+        description = "Maximal width of the hover window. Nil means no max.";
+      };
+      maxHeight = mkOption {
+        type = types.nullOr types.int;
+        default = null;
+        description = "Maximal height of the hover window. Nil means no max.";
+      };
+
+      autoFocus = mkNullableBoolDefault false "whether the hover action window gets automatically focused";
+    };
+
+    crateGraph = {
+      backend = mkNullableStrDefault "x11" ''
+        Backend used for displaying the graph
+        see: https://graphviz.org/docs/outputs/
+      '';
+
+      output = mkOption {
+        type = types.nullOr types.str;
+        default = null;
+        description = "where to store the output, nil for no output stored";
+      };
+
+      full = mkNullableBoolDefault true ''
+        true for all crates.io and external crates, false only the local crates
+      '';
+
+      enabledGraphvizBackends = mkOption {
+        type = types.nullOr (types.listOf types.str);
+        default = null;
+        description = ''
+          List of backends found on: https://graphviz.org/docs/outputs/
+          Is used for input validation and autocompletion
+        '';
+      };
+    };
+
+    server =
+      {
+        standalone = mkNullableBoolDefault true ''
+          standalone file support
+          setting it to false may improve startup time
+        '';
+      }
+      // (import ../nvim-lsp/rust-analyzer-config.nix lib);
+  };
+  config = let
+    cfg = config.plugins.rust-tools;
+  in
+    mkIf cfg.enable {
+      extraPlugins = with pkgs.vimPlugins; [nvim-lspconfig cfg.package];
+
+      plugins.lsp.postConfig = let
+        setupOptions = {
+          tools = {
+            executor =
+              if cfg.executor != null
+              then {__raw = ''require("rust-tools.executors").${cfg.executor}'';}
+              else null;
+
+            on_initialized =
+              if cfg.onIntialized != null
+              then {__raw = cfg.onIntialized;}
+              else null;
+
+            reload_workspace_from_cargo_toml = cfg.reloadWorkspaceFromCargoToml;
+            inlay_hints = let
+              cfgIH = cfg.inlayHints;
+            in {
+              auto = cfgIH.auto;
+              only_current_line = cfgIH.onlyCurrentLine;
+              show_parameter_hints = cfgIH.showParameterHints;
+              parameter_hints_prefix = cfgIH.parameterHintsPrefix;
+              other_hints_prefix = cfgIH.otherHintsPrefix;
+              max_len_align = cfgIH.maxLenAlign;
+              max_len_align_padding = cfgIH.maxLenAlignPadding;
+              right_align = cfgIH.rightAlign;
+              right_align_padding = cfgIH.rightAlignPadding;
+              highlight = cfgIH.highlight;
+            };
+
+            hover_actions = let
+              cfgHA = cfg.hoverActions;
+            in {
+              border = cfgHA.border;
+              max_width = cfgHA.maxWidth;
+              max_height = cfgHA.maxHeight;
+              auto_focus = cfgHA.autoFocus;
+            };
+
+            crate_graph = let
+              cfgCG = cfg.crateGraph;
+            in {
+              backend = cfgCG.backend;
+              output = cfgCG.output;
+              full = cfgCG.full;
+              enabled_graphviz_backends = cfgCG.enabledGraphvizBackends;
+            };
+          };
+          server = {
+            standalone = cfg.server.standalone;
+            settings.rust-analyzer = lib.filterAttrs (n: v: n != "standalone") cfg.server;
+            on_attach = {__raw = "__lspOnAttach";};
+          };
+        };
+      in ''
+        require('rust-tools').setup(${helpers.toLuaObject setupOptions})
+      '';
+    };
+}

plugins/nvim-lsp/default.nix

@@ -51,6 +51,12 @@ in
         description = "Code to be run before loading the LSP. Useful for requiring plugins";
         default = "";
       };
+
+      postConfig = mkOption {
+        type = types.lines;
+        description = "Code to be run after loading the LSP. This is an internal option";
+        default = "";
+      };
     };
   };
 
@@ -92,6 +98,8 @@ in
               require('lspconfig')[server.name].setup(options)
             end
           end
+
+          ${cfg.postConfig}
         end
         -- }}}
       '';