flake: Add pre-commit (#86)

.gitignore

@@ -30,3 +30,6 @@ go.work.sum
 
 # SQLite database
 /db/database.sqlite3
+
+# Pre-commit configuration (auto-generated)
+/.pre-commit-config.yaml

flake.nix

@@ -8,6 +8,11 @@
       url = "github:hercules-ci/flake-parts";
     };
 
+    git-hooks-nix = {
+      inputs.nixpkgs.follows = "nixpkgs";
+      url = "github:cachix/git-hooks.nix";
+    };
+
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
 
     treefmt-nix = {
@@ -23,6 +28,7 @@
         ./nix/devshells/flake-module.nix
         ./nix/formatter/flake-module.nix
         ./nix/packages/flake-module.nix
+        ./nix/pre-commit/flake-module.nix
       ];
       systems = [
         "x86_64-linux"

nix/devshells/flake-module.nix

@@ -14,6 +14,8 @@
         _DBMATE_VERSION = "${pkgs.dbmate.version}";
 
         shellHook = ''
+          ${config.pre-commit.installationScript}
+
           ${pkgs.gnused}/bin/sed -e "s:^\(go \)[0-9.]*$:\1''${_GO_VERSION}:" -i go.mod
           ${pkgs.gnused}/bin/sed -e "s:^\(ARG GO_VERSION=\).*$:\1''${_GO_VERSION}:" -i Dockerfile
           ${pkgs.gnused}/bin/sed -e "s:^\(ARG DBMATE_VERSION=\).*$:\1''${_DBMATE_VERSION}:" -i Dockerfile

nix/pre-commit/flake-module.nix

@@ -0,0 +1,22 @@
+{ inputs, ... }:
+
+{
+  imports = [
+    inputs.git-hooks-nix.flakeModule
+  ];
+
+  perSystem = {
+    pre-commit.check.enable = false;
+    pre-commit.settings.hooks = {
+      deadnix.enable = true;
+      gofmt.enable = true;
+      golangci-lint.enable = true;
+      no-commit-to-branch.enable = true;
+      no-commit-to-branch.settings.branch = [ "main" ];
+      nixfmt-rfc-style.enable = true;
+      statix.enable = true;
+      trim-trailing-whitespace.enable = true;
+      yamlfmt.enable = true;
+    };
+  };
+}