flake: Setup a devShell for haskell

flake.lock

@@ -103,6 +103,22 @@
       }
     },
     "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1696426674,
+        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
+    "flake-compat_2": {
       "flake": false,
       "locked": {
         "lastModified": 1668681692,
@@ -136,6 +152,45 @@
         "type": "github"
       }
     },
+    "flake-utils_2": {
+      "inputs": {
+        "systems": "systems_2"
+      },
+      "locked": {
+        "lastModified": 1701680307,
+        "narHash": "sha256-kAuep2h5ajznlPMD9rnQyffWG8EM/C73lejGofXvdM8=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "4022d587cbbfd70fe950c1e2083a02621806a725",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "gitignore": {
+      "inputs": {
+        "nixpkgs": [
+          "pre-commit-hooks",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1703887061,
+        "narHash": "sha256-gGPa9qWNc6eCXT/+Z5/zMkyYOuRZqeFZBDbopNZQkuY=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "43e1aa1308018f37118e34d3a9cb4f5e75dc11d5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
     "home-manager": {
       "inputs": {
         "nixpkgs": [
@@ -362,6 +417,22 @@
         "type": "github"
       }
     },
+    "nixpkgs-stable_2": {
+      "locked": {
+        "lastModified": 1704874635,
+        "narHash": "sha256-YWuCrtsty5vVZvu+7BchAxmcYzTMfolSPP5io8+WYCg=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3dc440faeee9e889fe2d1b4d25ad0f430d449356",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-23.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "nixpkgs-unstable": {
       "locked": {
         "lastModified": 1705316053,
@@ -441,6 +512,30 @@
         "type": "gitlab"
       }
     },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils_2",
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "nixpkgs-stable": "nixpkgs-stable_2"
+      },
+      "locked": {
+        "lastModified": 1708018599,
+        "narHash": "sha256-M+Ng6+SePmA8g06CmUZWi1AjG2tFBX9WCXElBHEKnyM=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "5df5a70ad7575f6601d91f0efec95dd9bc619431",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "agenix": "agenix",
@@ -452,13 +547,14 @@
         "nixpkgs": "nixpkgs",
         "nixpkgs-droid": "nixpkgs-droid",
         "nixpkgs-unstable": "nixpkgs-unstable",
+        "pre-commit-hooks": "pre-commit-hooks",
         "snm": "snm"
       }
     },
     "snm": {
       "inputs": {
         "blobs": "blobs",
-        "flake-compat": "flake-compat",
+        "flake-compat": "flake-compat_2",
         "nixpkgs": "nixpkgs_2",
         "nixpkgs-22_11": "nixpkgs-22_11",
         "nixpkgs-23_05": "nixpkgs-23_05",
@@ -494,6 +590,21 @@
         "type": "github"
       }
     },
+    "systems_2": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
     "utils": {
       "locked": {
         "lastModified": 1659877975,

flake.nix

@@ -4,6 +4,9 @@
     nixpkgs-droid.url = "github:NixOS/nixpkgs/nixos-23.05";
     nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixos-unstable";
 
+    pre-commit-hooks.url = "github:cachix/pre-commit-hooks.nix";
+    pre-commit-hooks.inputs.nixpkgs.follows = "nixpkgs";
+
     home-manager = {
       url = "github:nix-community/home-manager/release-23.11";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -45,51 +48,94 @@
     disko.inputs.nixpkgs.follows = "nixpkgs";
   };
 
-  outputs = { home-manager, nixpkgs, nixpkgs-unstable, ... }@inputs: {
+  outputs = { self, home-manager, nixpkgs, nixpkgs-unstable, pre-commit-hooks
-    nixosConfigurations."thrall" = nixpkgs.lib.nixosSystem {
+    , ... }@inputs: {
-      system = "x86_64-linux";
+      checks."x86_64-linux" = let
-      specialArgs = { inherit inputs; };
+        system = "x86_64-linux";
-      modules = let
+        pkgs = import nixpkgs { inherit system; };
-        postfix-overlay = final: prev: {
+      in {
-          postfix = nixpkgs-unstable.legacyPackages."x86_64-linux".postfix;
+        pre-commit-check = pre-commit-hooks.lib.${system}.run {
-        };
+          src = ./.;
-      in [
+          settings = { ormolu.defaultExtensions = [ "GHC2021" ]; };
-        ({ inputs, lib, ... }: {
+          tools.fourmolu = pkgs.haskellPackages.fourmolu;
-          nixpkgs = {
+          hooks = {
-            config.allowUnfree = true;
+            nixfmt.enable = true;
-            overlays = with inputs; [ emacs.overlay postfix-overlay ];
+            fourmolu.enable = true;
+            hpack.enable = true;
+            hlint.enable = true;
           };
-          nix.registry = lib.mapAttrs (_: value: { flake = value; }) inputs;
+        };
-        })
+      };
-        ./hosts/thrall
-        home-manager.nixosModules.home-manager
-        {
-          home-manager.useGlobalPkgs = true;
-          home-manager.useUserPackages = true;
-          home-manager.users.alex = import ./home/alex/cli.nix;
-        }
-      ];
-    };
 
-    nixosConfigurations."dregil" = nixpkgs-unstable.lib.nixosSystem {
+      nixosConfigurations."thrall" = nixpkgs.lib.nixosSystem {
-      system = "x86_64-linux";
+        system = "x86_64-linux";
-      specialArgs = { inherit inputs; };
+        specialArgs = { inherit inputs; };
-      modules = [ ./hosts/dregil ];
+        modules = let
-    };
+          postfix-overlay = final: prev: {
-
+            postfix = nixpkgs-unstable.legacyPackages."x86_64-linux".postfix;
-    nixosConfigurations."igor" = nixpkgs-unstable.lib.nixosSystem {
+          };
-      system = "x86_64-linux";
+        in [
-      specialArgs = { inherit inputs; };
+          ({ inputs, lib, ... }: {
-      modules = [ ./hosts/igor ];
+            nixpkgs = {
-    };
+              config.allowUnfree = true;
-
+              overlays = with inputs; [ emacs.overlay postfix-overlay ];
-    nixOnDroidConfigurations.default = with inputs;
+            };
-      nix-on-droid.lib.nixOnDroidConfiguration {
+            nix.registry = lib.mapAttrs (_: value: { flake = value; }) inputs;
-        modules = [
+          })
-          ./hosts/redmi
+          ./hosts/thrall
-          { nix.registry.nixpkgs.flake = nixpkgs-droid; }
+          home-manager.nixosModules.home-manager
-          { nix.nixPath = [ "nixpkgs=${nixpkgs-droid}" ]; }
+          {
+            home-manager.useGlobalPkgs = true;
+            home-manager.useUserPackages = true;
+            home-manager.users.alex = import ./home/alex/cli.nix;
+          }
         ];
       };
-  };
+
+      nixosConfigurations."dregil" = nixpkgs-unstable.lib.nixosSystem {
+        system = "x86_64-linux";
+        specialArgs = { inherit inputs; };
+        modules = [ ./hosts/dregil ];
+      };
+
+      nixosConfigurations."igor" = nixpkgs-unstable.lib.nixosSystem {
+        system = "x86_64-linux";
+        specialArgs = { inherit inputs; };
+        modules = [ ./hosts/igor ];
+      };
+
+      nixOnDroidConfigurations.default = with inputs;
+        nix-on-droid.lib.nixOnDroidConfiguration {
+          modules = [
+            ./hosts/redmi
+            { nix.registry.nixpkgs.flake = nixpkgs-droid; }
+            { nix.nixPath = [ "nixpkgs=${nixpkgs-droid}" ]; }
+          ];
+        };
+
+      devShells."x86_64-linux".default = let
+        system = "x86_64-linux";
+        pkgs = import nixpkgs { inherit system; };
+      in pkgs.haskellPackages.shellFor {
+        inherit (self.checks.${system}.pre-commit-check) shellHook;
+
+        packages = p: [ p.xmonad p.xmonad-contrib ];
+
+        withHoogle = true;
+
+        nativeBuildInputs = with pkgs; [
+          haskellPackages.haskell-language-server
+          haskellPackages.fourmolu
+          haskellPackages.hspec-discover
+          haskellPackages.doctest
+          haskellPackages.xmonad
+          haskellPackages.xmonad-contrib
+          cabal-install
+          ghcid
+          nixfmt
+          hpack
+          hlint
+        ];
+      };
+    };
 }