From c76ec1f33a9b81216430d8e0408e201a2a9d0ed6 Mon Sep 17 00:00:00 2001
From: Venkatesan Ravi <venkyrocker7777@gmail.com>
Date: Sun, 6 Apr 2025 09:44:42 +0000
Subject: [PATCH] languages/fish: init

---
 docs/release-notes/rl-0.8.md          |  1 +
 modules/plugins/languages/default.nix |  1 +
 modules/plugins/languages/fish.nix    | 95 +++++++++++++++++++++++++++
 3 files changed, 97 insertions(+)
 create mode 100644 modules/plugins/languages/fish.nix

diff --git a/docs/release-notes/rl-0.8.md b/docs/release-notes/rl-0.8.md
index 32460969..177ac16f 100644
--- a/docs/release-notes/rl-0.8.md
+++ b/docs/release-notes/rl-0.8.md
@@ -303,6 +303,7 @@
 - Disable mini.indentscope for applicable filetypes.
 - Fix fzf-lua having a hard dependency on fzf.
 - Enable inlay hints support - `config.vim.lsp.inlayHints`.
+- Add Fish language support under `vim.languages.fish`.
 
 [tebuevd](https://github.com/tebuevd):
 
diff --git a/modules/plugins/languages/default.nix b/modules/plugins/languages/default.nix
index c3312135..ae47c5a4 100644
--- a/modules/plugins/languages/default.nix
+++ b/modules/plugins/languages/default.nix
@@ -10,6 +10,7 @@ in {
     ./clang.nix
     ./css.nix
     ./elixir.nix
+    ./fish.nix
     ./fsharp.nix
     ./gleam.nix
     ./go.nix
diff --git a/modules/plugins/languages/fish.nix b/modules/plugins/languages/fish.nix
new file mode 100644
index 00000000..08953f76
--- /dev/null
+++ b/modules/plugins/languages/fish.nix
@@ -0,0 +1,95 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}: let
+  inherit (builtins) attrNames;
+  inherit (lib.options) mkEnableOption mkOption;
+  inherit (lib.modules) mkIf mkMerge;
+  inherit (lib.meta) getExe;
+  inherit (lib.lists) isList;
+  inherit (lib.types) bool either enum listOf package str;
+  inherit (lib.nvim.lua) expToLua toLuaObject;
+  inherit (lib.nvim.types) mkGrammarOption;
+
+  cfg = config.vim.languages.fish;
+
+  defaultFormat = "fish_indent";
+
+  formats = {
+    fish_indent = {
+      cmd = "${pkgs.fish}/bin/fish_indent";
+    };
+  };
+in {
+  options.vim.languages.fish = {
+    enable = mkEnableOption "Fish language support";
+
+    format = {
+      enable = mkOption {
+        type = bool;
+        default = config.vim.languages.enableFormat;
+        description = "Enable Fish formatting";
+      };
+
+      type = mkOption {
+        type = enum (attrNames formats);
+        default = defaultFormat;
+        description = "Fish formatter to use";
+      };
+
+      cmd = mkOption {
+        type = str;
+        default = formats.${cfg.format.type}.cmd;
+        description = "Path to fish formatter executable";
+      };
+    };
+
+    lsp = {
+      enable = mkEnableOption "Fish LSP support via fish-lsp" // {default = config.vim.languages.enableLSP;};
+
+      package = mkOption {
+        description = "fish-lsp package, or the command to run as a list of strings";
+        type = either package (listOf str);
+        default = pkgs.fish-lsp;
+      };
+    };
+
+    treesitter = {
+      enable = mkEnableOption "Fish Treesitter support" // {default = config.vim.languages.enableTreesitter;};
+      package = mkGrammarOption pkgs "fish";
+    };
+  };
+
+  config = mkMerge [
+    (mkIf cfg.format.enable {
+      vim.formatter.conform-nvim = {
+        enable = true;
+        setupOpts.formatters_by_ft.fish = [cfg.format.type];
+        setupOpts.formatters.${cfg.format.type} = {command = cfg.format.cmd;};
+      };
+    })
+
+    (mkIf (cfg.enable && cfg.lsp.enable) {
+      vim.lsp.lspconfig.enable = true;
+      vim.lsp.lspconfig.sources.fish-lsp = let
+        cmd =
+          if isList cfg.lsp.package
+          then expToLua cfg.lsp.package
+          else toLuaObject ["${getExe cfg.lsp.package}" "start"];
+      in ''
+        lspconfig.fish_lsp.setup {
+          capabilities = capabilities;
+          on_attach = default_on_attach;
+          cmd = ${cmd};
+        }
+      '';
+    })
+
+    (mkIf cfg.treesitter.enable {
+      vim.treesitter.enable = true;
+      vim.treesitter.grammars = [cfg.treesitter.package];
+    })
+  ];
+}