librewolf: add nixos test

- support librewolf in the firefox nixos test
- use the correct binary name
- ensure autoplay is always on for the audio test, since
  librewolf disables it by default

nixos/tests/all-tests.nix

@@ -278,6 +278,7 @@ in {
   libreddit = handleTest ./libreddit.nix {};
   libresprite = handleTest ./libresprite.nix {};
   libreswan = handleTest ./libreswan.nix {};
+  librewolf = handleTest ./firefox.nix { firefoxPackage = pkgs.librewolf; };
   lidarr = handleTest ./lidarr.nix {};
   lightdm = handleTest ./lightdm.nix {};
   limesurvey = handleTest ./limesurvey.nix {};

nixos/tests/firefox.nix

@@ -1,5 +1,14 @@
-import ./make-test-python.nix ({ pkgs, firefoxPackage, ... }: {
-  name = "firefox";
+import ./make-test-python.nix ({ pkgs, firefoxPackage, ... }:
+let firefoxPackage' = firefoxPackage.override (args: {
+      extraPrefsFiles = (args.extraPrefsFiles or []) ++ [
+        # make sure that autoplay is enabled by default for the audio test
+        (builtins.toString (builtins.toFile "autoplay-pref.js" ''defaultPref("media.autoplay.default",0);''))
+      ];
+  });
+
+in
+{
+  name = firefoxPackage'.unwrapped.binaryName;
   meta = with pkgs.lib.maintainers; {
     maintainers = [ eelco shlevy ];
   };
@@ -9,7 +18,7 @@ import ./make-test-python.nix ({ pkgs, firefoxPackage, ... }: {
 
     { imports = [ ./common/x11.nix ];
       environment.systemPackages = [
-        firefoxPackage
+        firefoxPackage'
         pkgs.xdotool
       ];
 
@@ -88,7 +97,7 @@ import ./make-test-python.nix ({ pkgs, firefoxPackage, ... }: {
 
       with subtest("Wait until Firefox has finished loading the Valgrind docs page"):
           machine.execute(
-              "xterm -e 'firefox file://${pkgs.valgrind.doc}/share/doc/valgrind/html/index.html' >&2 &"
+              "xterm -e '${firefoxPackage'.unwrapped.binaryName} file://${pkgs.valgrind.doc}/share/doc/valgrind/html/index.html' >&2 &"
           )
           machine.wait_for_window("Valgrind")
           machine.sleep(40)
@@ -96,7 +105,7 @@ import ./make-test-python.nix ({ pkgs, firefoxPackage, ... }: {
       with subtest("Check whether Firefox can play sound"):
           with record_audio(machine):
               machine.succeed(
-                  "firefox file://${pkgs.sound-theme-freedesktop}/share/sounds/freedesktop/stereo/phone-incoming-call.oga >&2 &"
+                  "${firefoxPackage'.unwrapped.binaryName} file://${pkgs.sound-theme-freedesktop}/share/sounds/freedesktop/stereo/phone-incoming-call.oga >&2 &"
               )
               wait_for_sound(machine)
           machine.copy_from_vm("/tmp/record.wav")

pkgs/applications/networking/browsers/librewolf/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, lib, callPackage, buildMozillaMach }:
+{ stdenv, lib, callPackage, buildMozillaMach, nixosTests }:
 
 let
   librewolf-src = callPackage ./librewolf.nix { };
@@ -22,6 +22,7 @@ in
     maxSilent = 14400; # 4h, double the default of 7200s (c.f. #129212, #129115)
     license = lib.licenses.mpl20;
   };
+  tests = [ nixosTests.librewolf ];
   updateScript = callPackage ./update.nix {
     attrPath = "librewolf-unwrapped";
   };