Add nixpkgs-fmt + associated checks

default.nix

@@ -12,17 +12,22 @@
 
 let
   filterMesonBuild = dir: builtins.filterSource
-    (path: type: type != "directory" || baseNameOf path != "build") dir;
+    (path: type: type != "directory" || baseNameOf path != "build")
+    dir;
 in
 stdenv.mkDerivation rec {
   pname = "nix-eval-jobs";
   version = "0.0.1";
   src = if srcDir == null then filterMesonBuild ./. else srcDir;
   buildInputs = [
-    nlohmann_json nixFlakes boost
+    nlohmann_json
+    nixFlakes
+    boost
   ];
   nativeBuildInputs = [
-    meson pkg-config ninja
+    meson
+    pkg-config
+    ninja
     # nlohmann_json can be only discovered via cmake files
     cmake
   ];

flake.nix

@@ -15,7 +15,8 @@
 
         checks = {
 
-          editorconfig = pkgs.runCommand "editorconfig-checks" {
+          editorconfig = pkgs.runCommand "editorconfig-check"
+            {
               nativeBuildInputs = [
                 pkgs.editorconfig-checker
               ];
@@ -24,6 +25,16 @@
             touch $out
           '';
 
+          nixpkgs-fmt = pkgs.runCommand "fmt-check"
+            {
+              nativeBuildInputs = [
+                pkgs.nixpkgs-fmt
+              ];
+            } ''
+            nixpkgs-fmt --check .
+            touch $out
+          '';
+
           build = packages.nix-eval-jobs;
 
         };
@@ -31,5 +42,6 @@
         defaultPackage = self.packages.${system}.nix-eval-jobs;
         devShell = pkgs.callPackage ./shell.nix drvArgs;
 
-      });
+      }
+    );
 }

shell.nix

@@ -8,6 +8,8 @@
 
     pkgs.editorconfig-checker
 
+    pkgs.nixpkgs-fmt
+
     (pkgs.python3.withPackages (ps: [
       ps.pytest
     ]))

tests/assets/flake.nix

@@ -1,9 +1,11 @@
 {
   inputs.nixpkgs.url = "github:NixOS/nixpkgs";
 
-  outputs = { self, nixpkgs }: let
+  outputs = { self, nixpkgs }:
+    let
       pkgs = nixpkgs.legacyPackages.x86_64-linux;
-  in {
+    in
+    {
       hydraJobs = {
         builtJob = pkgs.writeText "job1" "job1";
         substitutedJob = pkgs.hello;