modules/treefmt: init

modules/treefmt/check.nix

@@ -0,0 +1,21 @@
+{
+  pkgs,
+  self,
+}:
+let
+  treefmtWrapped =
+    (self.wrapperModules.treefmt.apply {
+      inherit pkgs;
+      settings = {
+        formatter.nixfmt = {
+          command = "nixpkgs-fmt";
+          includes = [ "*.nix" ];
+        };
+      };
+      programs = [ pkgs.nixpkgs-fmt ];
+    }).wrapper;
+in
+pkgs.runCommand "treefmt-test" { } ''
+  "${treefmtWrapped}/bin/treefmt" --version | grep -q "treefmt"
+  touch $out
+''

modules/treefmt/module.nix

@@ -0,0 +1,96 @@
+{
+  config,
+  lib,
+  wlib,
+  ...
+}:
+let
+  tomlFmt = config.pkgs.formats.toml { };
+in
+{
+  _class = "wrapper";
+
+  options = {
+    settings = lib.mkOption {
+      type = lib.types.submodule {
+        freeformType = tomlFmt.type;
+        options = {
+          excludes = lib.mkOption {
+            type = lib.types.listOf lib.types.str;
+            default = [ ];
+            description = "Global list of paths to exclude. Supports glob.";
+          };
+          formatter = lib.mkOption {
+            type = lib.types.attrsOf (
+              lib.types.submodule {
+                freeformType = tomlFmt.type;
+                options = {
+                  command = lib.mkOption {
+                    type = lib.types.str;
+                    description = "Executable name or path obeying the treefmt formatter spec.";
+                  };
+                  options = lib.mkOption {
+                    type = lib.types.listOf lib.types.str;
+                    default = [ ];
+                    description = "Arguments to pass to the command.";
+                  };
+                  includes = lib.mkOption {
+                    type = lib.types.listOf lib.types.str;
+                    description = "File patterns to include for formatting. Supports glob.";
+                  };
+                  excludes = lib.mkOption {
+                    type = lib.types.listOf lib.types.str;
+                    default = [ ];
+                    description = "File patterns to exclude from formatting.";
+                  };
+                };
+              }
+            );
+            default = { };
+            description = "Set of formatters to use.";
+          };
+        };
+      };
+      default = { };
+      description = ''
+        Structured treefmt configuration written to treefmt.toml.
+        See <https://treefmt.com/latest/getting-started/configure/>
+      '';
+    };
+
+    programs = lib.mkOption {
+      type = lib.types.listOf lib.types.package;
+      default = [ ];
+      description = ''
+        Formatter packages to add to PATH.
+      '';
+    };
+
+    "treefmt.toml" = lib.mkOption {
+      type = wlib.types.file config.pkgs;
+      default.path = tomlFmt.generate "treefmt.toml" (
+        lib.filterAttrsRecursive (_: v: v != null) config.settings
+      );
+      description = ''
+        The generated treefmt.toml configuration file.
+      '';
+    };
+  };
+
+  config.package = config.pkgs.treefmt;
+
+  config.flags = {
+    "--config-file" = toString config."treefmt.toml".path;
+  };
+
+  config.extraPackages = config.programs;
+
+  config.meta.maintainers = [
+    {
+      name = "Alexander Kenji Berthold";
+      github = "a-kenji";
+      githubId = 65275785;
+    }
+  ];
+  config.meta.platforms = lib.platforms.all;
+}