tests: isolate QML font configuration

Signed-off-by: Patrizio Bekerle <patrizio@bekerle.com>

Author: pbek

.github/workflows/scripts/run-qml-tests.sh

@@ -15,6 +15,10 @@ if [[ -n "${QML_TEST_IMPORT_PATH:-}" ]]; then
   qml_import_arguments=(-import "$QML_TEST_IMPORT_PATH")
 fi
 
+if [[ -n "${QML_TEST_FONTCONFIG_FILE:-}" ]]; then
+  export FONTCONFIG_FILE="$QML_TEST_FONTCONFIG_FILE"
+fi
+
 if ((${#test_directories[@]} == 0)); then
   printf 'No QML tests were found\n'
   exit 0

devenv.nix

@@ -5,6 +5,14 @@
 
 {
   packages = [ pkgs.qt6.qtdeclarative ];
+  env.QML_TEST_FONTCONFIG_FILE = pkgs.writeText "qml-test-fonts.conf" ''
+    <?xml version="1.0"?>
+    <!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
+    <fontconfig>
+      <dir>${pkgs.dejavu_fonts}/share/fonts/truetype</dir>
+      <cachedir prefix="xdg">fontconfig</cachedir>
+    </fontconfig>
+  '';
   env.QML_TEST_IMPORT_PATH = "${pkgs.qt6.qtdeclarative}/lib/qt-6/qml";
 
   # https://devenv.sh/git-hooks/