yopass: add module

Adds programs.yopass for managing the yopass CLI configuration file
(~/.config/yopass/defaults.yml), with an NMT test verifying the
generated settings.

Assisted-by: Claude Fable 5

modules/misc/news/2026/08/2026-08-29_08-55-25.nix

@@ -0,0 +1,9 @@
+{
+  time = "2026-08-29T06:55:25+00:00";
+  message = ''
+    A new module is available: 'programs.yopass'.
+
+    Yopass is a tool for sharing secrets and files securely. The module
+    manages the yopass command line client's configuration file.
+  '';
+}

modules/programs/yopass.nix

@@ -0,0 +1,52 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.programs.yopass;
+in
+{
+  meta.maintainers = [ lib.maintainers.fraggerfox ];
+
+  options.programs.yopass = {
+    enable = lib.mkEnableOption "Yopass, a tool for sharing secrets and files securely";
+
+    package = lib.mkPackageOption pkgs "yopass" { nullable = true; };
+
+    settings = lib.mkOption {
+      type = lib.types.attrsOf (
+        lib.types.oneOf [
+          lib.types.bool
+          lib.types.int
+          lib.types.str
+        ]
+      );
+      default = { };
+      description = ''
+        Configuration written to
+        {file}`$XDG_CONFIG_HOME/yopass/defaults.yml`.
+
+        See the [CLI documentation](https://yopass.se/docs/cli) for the
+        full list of available settings (`api`, `api-token`, `url`,
+        `one-time`, `expiration`).
+      '';
+      example = {
+        api = "https://api.example.com";
+        url = "https://example.com";
+        "one-time" = false;
+        expiration = "1d";
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    home.packages = lib.mkIf (cfg.package != null) [ cfg.package ];
+
+    xdg.configFile."yopass/defaults.yml" = lib.mkIf (cfg.settings != { }) {
+      text = lib.generators.toYAML { } cfg.settings;
+    };
+  };
+}

tests/modules/programs/yopass/default.nix

@@ -0,0 +1,3 @@
+{
+  yopass-settings = ./settings.nix;
+}

tests/modules/programs/yopass/settings.nix

@@ -0,0 +1,19 @@
+{
+  programs.yopass = {
+    enable = true;
+    settings = {
+      api = "https://api.example.com";
+      url = "https://example.com";
+      "one-time" = false;
+      expiration = "1d";
+    };
+  };
+
+  test.stubs.yopass = { };
+
+  nmt.script = ''
+    assertFileExists home-files/.config/yopass/defaults.yml
+    assertFileContent home-files/.config/yopass/defaults.yml \
+      ${./settings.yml}
+  '';
+}

tests/modules/programs/yopass/settings.yml

@@ -0,0 +1 @@
+{"api":"https://api.example.com","expiration":"1d","one-time":false,"url":"https://example.com"}