From 0cfc7e63a648b24efb9c2c783a3422bdac408958 Mon Sep 17 00:00:00 2001
From: Henri Menke <henri@henrimenke.de>
Date: Wed, 18 Jan 2023 15:40:42 +0100
Subject: [PATCH] nixos/zram-generator: add test

---
 nixos/tests/all-tests.nix                    |  1 +
 nixos/tests/zram-generator.nix               | 18 ++++++++++++++++++
 pkgs/tools/system/zram-generator/default.nix |  5 +++++
 3 files changed, 24 insertions(+)
 create mode 100644 nixos/tests/zram-generator.nix

diff --git a/nixos/tests/all-tests.nix b/nixos/tests/all-tests.nix
index b4bd8ef3e0f2..76f9b512b0f4 100644
--- a/nixos/tests/all-tests.nix
+++ b/nixos/tests/all-tests.nix
@@ -752,6 +752,7 @@ in {
   zigbee2mqtt = handleTest ./zigbee2mqtt.nix {};
   zoneminder = handleTest ./zoneminder.nix {};
   zookeeper = handleTest ./zookeeper.nix {};
+  zram-generator = handleTest ./zram-generator.nix {};
   zrepl = handleTest ./zrepl.nix {};
   zsh-history = handleTest ./zsh-history.nix {};
 }
diff --git a/nixos/tests/zram-generator.nix b/nixos/tests/zram-generator.nix
new file mode 100644
index 000000000000..affa081bcc35
--- /dev/null
+++ b/nixos/tests/zram-generator.nix
@@ -0,0 +1,18 @@
+import ./make-test-python.nix {
+  name = "zram-generator";
+
+  nodes.machine = { pkgs, ... }: {
+    environment.etc."systemd/zram-generator.conf".text = ''
+      [zram0]
+      zram-size = ram / 2
+    '';
+    systemd.packages = [ pkgs.zram-generator ];
+    systemd.services."systemd-zram-setup@".path = [ pkgs.util-linux ]; # for mkswap
+  };
+
+  testScript = ''
+    machine.wait_for_unit("systemd-zram-setup@zram0.service")
+    assert "zram0" in machine.succeed("zramctl -n")
+    assert "zram0" in machine.succeed("swapon --show --noheadings")
+  '';
+}
diff --git a/pkgs/tools/system/zram-generator/default.nix b/pkgs/tools/system/zram-generator/default.nix
index 393944a2451b..00ead13d9307 100644
--- a/pkgs/tools/system/zram-generator/default.nix
+++ b/pkgs/tools/system/zram-generator/default.nix
@@ -6,6 +6,7 @@
 , ronn
 , systemd
 , kmod
+, nixosTests
 }:
 
 stdenv.mkDerivation rec {
@@ -50,6 +51,10 @@ stdenv.mkDerivation rec {
     "SYSTEMD_SYSTEM_GENERATOR_DIR=$(out)/lib/systemd/system-generators"
   ];
 
+  passthru.tests = {
+    inherit (nixosTests) zram-generator;
+  };
+
   meta = with lib; {
     homepage = "https://github.com/systemd/zram-generator";
     license = licenses.mit;