aria2: add module

PR #1202

tests/modules/programs/aria2/default.nix

@@ -0,0 +1 @@
+{ aria2-settings = ./settings.nix; }

tests/modules/programs/aria2/settings.nix

@@ -0,0 +1,41 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+{
+  config = {
+    programs.aria2 = {
+      enable = true;
+
+      settings = {
+        listen-port = 60000;
+        dht-listen-port = 60000;
+        seed-ratio = 1.0;
+        max-upload-limit = "50K";
+        ftp-pasv = true;
+      };
+
+      extraConfig = ''
+        # Extra aria2 configuration.
+      '';
+    };
+
+    nixpkgs.overlays =
+      [ (self: super: { aria2 = pkgs.writeScriptBin "dummy-aria2" ""; }) ];
+
+    nmt.script = ''
+      assertFileContent \
+        home-files/.config/aria2/aria2.conf \
+        ${
+          pkgs.writeText "aria2-expected-config.conf" ''
+            dht-listen-port=60000
+            ftp-pasv=true
+            listen-port=60000
+            max-upload-limit=50K
+            seed-ratio=1.000000
+            # Extra aria2 configuration.
+          ''
+        }
+    '';
+  };
+}