flake: add treefmt

Author: jaen

flake.lock

@@ -8,10 +8,26 @@
     androidPkgs.url = "github:tadfisher/android-nixpkgs/stable";
 
     flake-compat.url = "github:nix-community/flake-compat";
+
+    treefmt.url = "github:numtide/treefmt";
+
+    treefmt-nix.url = "github:numtide/treefmt-nix";
+    treefmt-nix.inputs.nixpkgs.follows = "nixpkgs-unstable";
   };
 
-  outputs = { self, nixpkgs, nixpkgs-unstable, androidPkgs, flake-compat,  ... }@inputs: let
+  outputs = { 
+    self, nixpkgs, nixpkgs-unstable, androidPkgs, flake-compat, treefmt, treefmt-nix, ...
+  }@inputs: let
     pkgs = import ./pkgs/default.nix { inherit inputs; };
+    
+    treeFmt = treefmt-nix.lib.evalModule pkgs ./treefmt.nix;
+    pythonForUpdaterScripts = pkgs.python3.withPackages (
+      p: with p; [
+        mypy
+        flake8
+        pytest
+      ]
+    );
   in {
     # robotnixSystem evaluates a robotnix configuration
     lib.robotnixSystem = configuration: import ./default.nix {
@@ -33,9 +49,9 @@
 
     devShell.x86_64-linux = pkgs.mkShell {
       name = "robotnix-scripts";
+      inputsFrom = [ treeFmt.config.build.devShell ];
       nativeBuildInputs = with pkgs; [
-        # For android updater scripts
-        (python3.withPackages (p: with p; [ mypy flake8 pytest ]))
+        pythonForUpdaterScripts
         gitRepo nix-prefetch-git
         curl pup jq
         shellcheck
@@ -49,5 +65,11 @@
       ];
       PYTHONPATH=./scripts;
     };
+
+    formatter.x86_64-linux = treeFmt.config.build.wrapper;
+
+    checks.x86_64-linux = {
+      formatting = treeFmt.config.build.check self;
+    };
   };
 }

flake.nix

@@ -1,4 +1,9 @@
 { inputs }:
+let
+  inherit (inputs) nixpkgs-unstable;
+
+  unstablePkgs = nixpkgs-unstable.legacyPackages.x86_64-linux;
+in
 self: super: {
   android-emulator = super.callPackage ./android-emulator {};
 
@@ -36,6 +41,10 @@ self: super: {
 
   gitRepo = super.callPackage ./gitRepo { inherit inputs; };
 
+  nixfmt-rfc-style = unstablePkgs.nixfmt-rfc-style;
+
+  treefmt2 = inputs.treefmt.packages.x86_64-linux.treefmt;
+  
   ###
 
   # Robotnix helper derivations