nixos/fontconfig: add test for allowBitmaps

nixos/tests/all-tests.nix

@@ -566,6 +566,7 @@ in
   fluent-bit = runTest ./fluent-bit.nix;
   fluentd = runTest ./fluentd.nix;
   fluidd = runTest ./fluidd.nix;
+  fontconfig-bitmap-fonts = runTest ./fontconfig-bitmap-fonts.nix;
   fontconfig-default-fonts = runTest ./fontconfig-default-fonts.nix;
   forgejo = import ./forgejo.nix {
     inherit runTest;

nixos/tests/fontconfig-bitmap-fonts.nix

@@ -0,0 +1,17 @@
+{ lib, ... }:
+{
+  name = "fontconfig-bitmap-fonts";
+
+  nodes.machine =
+    { config, pkgs, ... }:
+    {
+      fonts.packages = [
+        pkgs.terminus_font
+      ];
+      fonts.fontconfig.allowBitmaps = true;
+    };
+
+  testScript = ''
+    machine.succeed("fc-list | grep Terminus")
+  '';
+}