Merge pull request #54 from nix-community/pre-commit-style

Enforce Nix Style

.gitignore

@@ -1,3 +1,4 @@
 result*
 /.direnv
 target
+/.pre-commit-config.yaml

flake.lock

@@ -59,6 +59,22 @@
         "type": "github"
       }
     },
+    "flake-compat_3": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1668681692,
+        "narHash": "sha256-Ht91NGdewz8IQLtWZ9LCeNXMSXHUss+9COoqu6JLmXU=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "009399224d5e398d03b22badca40a37ac85412a1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-parts": {
       "inputs": {
         "nixpkgs-lib": "nixpkgs-lib"
@@ -92,6 +108,27 @@
         "type": "github"
       }
     },
+    "gitignore": {
+      "inputs": {
+        "nixpkgs": [
+          "pre-commit-hooks-nix",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1660459072,
+        "narHash": "sha256-8DFJjXG8zqoONA1vXtgeKXy68KdJL5UaXR8NtVMUbx8=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "a20de23b925fd8264fd7fad6454652e142fd7f73",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1673039641,
@@ -126,6 +163,22 @@
         "type": "github"
       }
     },
+    "nixpkgs-stable": {
+      "locked": {
+        "lastModified": 1671271954,
+        "narHash": "sha256-cSvu+bnvN08sOlTBWbBrKaBHQZq8mvk8bgpt0ZJ2Snc=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "d513b448cc2a6da2c8803e3c197c9fc7e67b19e3",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-22.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "nixpkgs-test": {
       "locked": {
         "lastModified": 1671812130,
@@ -142,6 +195,32 @@
         "type": "github"
       }
     },
+    "pre-commit-hooks-nix": {
+      "inputs": {
+        "flake-compat": "flake-compat_3",
+        "flake-utils": [
+          "flake-utils"
+        ],
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "nixpkgs-stable": "nixpkgs-stable"
+      },
+      "locked": {
+        "lastModified": 1672912243,
+        "narHash": "sha256-QnQeKUjco2kO9J4rBqIBPp5XcOMblIMnmyhpjeaJBYc=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "a4548c09eac4afb592ab2614f4a150120b29584c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "crane": "crane",
@@ -150,6 +229,7 @@
         "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs",
         "nixpkgs-test": "nixpkgs-test",
+        "pre-commit-hooks-nix": "pre-commit-hooks-nix",
         "rust-overlay": "rust-overlay"
       }
     },

flake.nix

@@ -7,6 +7,12 @@
 
     flake-parts.url = "github:hercules-ci/flake-parts";
 
+    pre-commit-hooks-nix = {
+      url = "github:cachix/pre-commit-hooks.nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.flake-utils.follows = "flake-utils";
+    };
+
     # We only have this input to pass it to other dependencies and
     # avoid having mulitple versions in our dependencies.
     flake-utils.url = "github:numtide/flake-utils";
@@ -35,6 +41,9 @@
       imports = [
         # Derive the output overlay automatically from all packages that we define.
         inputs.flake-parts.flakeModules.easyOverlay
+
+        # Formatting and quality checks.
+        inputs.pre-commit-hooks-nix.flakeModule
       ];
 
       flake.nixosModules.lanzaboote = moduleWithSystem (
@@ -45,7 +54,8 @@
           ];
 
           boot.lanzaboote.package = perSystem.config.packages.lanzatool;
-        });
+        }
+      );
 
       systems = [
         "x86_64-linux"
@@ -54,7 +64,8 @@
         # "aarch64-linux"
       ];
 
-      perSystem = { config, system, pkgs, ... }: let
+      perSystem = { config, system, pkgs, ... }:
+        let
           pkgs = import nixpkgs {
             system = system;
             overlays = [
@@ -116,11 +127,13 @@
           };
 
           lanzatool-unwrapped = lanzatoolCrane.package;
-      in {
+        in
+        {
           packages = {
             inherit lanzaboote;
 
-          lanzatool = pkgs.runCommand "lanzatool" {
+            lanzatool = pkgs.runCommand "lanzatool"
+              {
                 nativeBuildInputs = [ pkgs.makeWrapper ];
               } ''
               mkdir -p $out/bin
@@ -146,12 +159,26 @@
             lanzabooteModule = self.nixosModules.lanzaboote;
           });
 
+          pre-commit = {
+            check.enable = true;
+
+            settings.hooks = {
+              nixpkgs-fmt.enable = true;
+            };
+          };
+
           devShells.default = pkgs.mkShell {
-          packages = let
+            shellHook = ''
+              ${config.pre-commit.installationScript}
+            '';
+
+            packages =
+              let
                 uefi-run = pkgs.callPackage ./nix/packages/uefi-run.nix {
                   inherit craneLib;
                 };
-          in [
+              in
+              [
                 uefi-run
                 pkgs.openssl
                 (pkgs.sbctl.override {