From 1af12636cd4f519a9c0110179d03e99caa236ecd Mon Sep 17 00:00:00 2001
From: Snoweuph <snow@euph.email>
Date: Sat, 24 Jan 2026 00:18:32 +0100
Subject: [PATCH] language/just: formatter

---
 docs/manual/release-notes/rl-0.9.md |  4 ++++
 modules/plugins/languages/just.nix  | 37 +++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/docs/manual/release-notes/rl-0.9.md b/docs/manual/release-notes/rl-0.9.md
index c38d2421..234ddfa0 100644
--- a/docs/manual/release-notes/rl-0.9.md
+++ b/docs/manual/release-notes/rl-0.9.md
@@ -144,3 +144,7 @@
 [Machshev](https://github.com/machshev):
 
 - Added `ruff` and `ty` LSP support for Python under `programs.python`.
+
+[Snoweuph](https://github.com/snoweuph)
+
+- Added Formatting support to the `just` language through its builtin formatter.
diff --git a/modules/plugins/languages/just.nix b/modules/plugins/languages/just.nix
index 7645f255..1d12e7a8 100644
--- a/modules/plugins/languages/just.nix
+++ b/modules/plugins/languages/just.nix
@@ -23,6 +23,18 @@
       root_markers = [".git" "justfile"];
     };
   };
+
+  defaultFormat = ["just"];
+
+  formats = {
+    just = {
+      command = getExe pkgs.just;
+      args = [
+        "--unstable"
+        "--fmt"
+      ];
+    };
+  };
 in {
   options.vim.languages.just = {
     enable = mkEnableOption "Just support";
@@ -42,6 +54,16 @@ in {
         description = "Just LSP server to use";
       };
     };
+
+    format = {
+      enable = mkEnableOption "Justfile formatting" // {default = config.vim.languages.enableFormat;};
+
+      type = mkOption {
+        description = "Justfile formatter to use";
+        type = listOf (enum (attrNames formats));
+        default = defaultFormat;
+      };
+    };
   };
 
   config = mkIf cfg.enable (mkMerge [
@@ -60,5 +82,20 @@ in {
         })
         cfg.lsp.servers;
     })
+
+    (mkIf cfg.format.enable {
+      vim.formatter.conform-nvim = {
+        enable = true;
+        setupOpts = {
+          formatters_by_ft.just = cfg.format.type;
+          formatters =
+            mapListToAttrs (name: {
+              inherit name;
+              value = formats.${name};
+            })
+            cfg.format.type;
+        };
+      };
+    })
   ]);
 }