Implement new module design

Based on #196.

Author: sandydoo

modules/hook.nix

@@ -0,0 +1,156 @@
+{ config, name, lib, ... }:
+
+
+let
+  inherit (lib) mkOption types;
+  cfg = config.options;
+in
+{
+  options = {
+    enable = mkOption {
+      type = types.bool;
+      description = lib.mdDoc "Whether to enable this pre-commit hook.";
+      default = false;
+    };
+
+    raw = mkOption {
+      type = types.attrsOf types.unspecified;
+      description = lib.mdDoc
+        ''
+          Raw fields of a pre-commit hook. This is mostly for internal use but
+          exposed in case you need to work around something.
+
+          Default: taken from the other hook options.
+        '';
+    };
+
+    name = mkOption {
+      type = types.str;
+      defaultText = lib.literalMD "internal name, same as `id`";
+      default = name;
+      description = lib.mdDoc
+        ''
+          The name of the hook - shown during hook execution.
+        '';
+    };
+
+    description = mkOption {
+      type = types.str;
+      description = lib.mdDoc
+        ''
+          Description of the hook. used for metadata purposes only.
+        '';
+      default = "";
+    };
+
+    package = mkOption {
+      type = types.package;
+      description = lib.mdDoc
+        ''
+          The package that provides the hook.
+        '';
+    };
+
+    entry = mkOption {
+      type = types.str;
+      description = lib.mdDoc
+        ''
+          The entry point - the executable to run. {option}`entry` can also contain arguments that will not be overridden, such as `entry = "autopep8 -i";`.
+        '';
+    };
+
+    language = mkOption {
+      type = types.str;
+      description = lib.mdDoc
+        ''
+          The language of the hook - tells pre-commit how to install the hook.
+        '';
+      default = "system";
+    };
+
+    files = mkOption {
+      type = types.str;
+      description = lib.mdDoc
+        ''
+          The pattern of files to run on.
+        '';
+      default = "";
+    };
+
+    types = mkOption {
+      type = types.listOf types.str;
+      description = lib.mdDoc
+        ''
+          List of file types to run on. See [Filtering files with types](https://pre-commit.com/#plugins).
+        '';
+      default = [ "file" ];
+    };
+
+    types_or = mkOption {
+      type = types.listOf types.str;
+      description = lib.mdDoc
+        ''
+          List of file types to run on, where only a single type needs to match.
+        '';
+      default = [ ];
+    };
+
+    excludes = mkOption {
+      type = types.listOf types.str;
+      description = lib.mdDoc
+        ''
+          Exclude files that were matched by these patterns.
+        '';
+      default = [ ];
+    };
+
+    pass_filenames = mkOption {
+      type = types.bool;
+      description = lib.mdDoc ''
+        Whether to pass filenames as arguments to the entry point.
+      '';
+      default = true;
+    };
+
+    fail_fast = mkOption {
+      type = types.bool;
+      description = lib.mdDoc ''
+        if true pre-commit will stop running hooks if this hook fails.
+      '';
+      default = false;
+    };
+
+    require_serial = mkOption {
+      type = types.bool;
+      description = lib.mdDoc ''
+        if true this hook will execute using a single process instead of in parallel.
+      '';
+      default = false;
+    };
+
+    stages = mkOption {
+      type = types.listOf types.str;
+      description = lib.mdDoc ''
+        Confines the hook to run at a particular stage.
+      '';
+      default = cfg.default_stages;
+      defaultText = (lib.literalExpression or lib.literalExample) "default_stages";
+    };
+
+    verbose = mkOption {
+      type = types.bool;
+      default = false;
+      description = lib.mdDoc ''
+        forces the output of the hook to be printed even when the hook passes.
+      '';
+    };
+
+    always_run = mkOption {
+      type = types.bool;
+      default = false;
+      description = lib.mdDoc ''
+        if true this hook will run even if there are no matching files.
+      '';
+    };
+  };
+}