Fixed issue #183.

.github/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install psutil pytest
+          pip install psutil platformdirs pytest
 
       - name: Install package (no-deps to avoid GUI reqs)
         run: pip install -e . --no-deps

src/lufus/gui/gui.py

@@ -1099,10 +1099,16 @@ def dropEvent(self, event):
 
     def browse_file(self):
         # open file dialog to select image :D
+        from lufus.user_paths import get_best_starting_dir
+        # ^ Uses the XDG_DOWNALOD_DIR that was detected and shoved into a variable
+
+        starting_dir = get_best_starting_dir()
+        self.log_message(f"Opening file browser at: {starting_dir}")
+
         file_name, _ = QFileDialog.getOpenFileName(
             self,
             self._T.get("dlg_select_image_title", "Select Image"),
-            "",
+            starting_dir,
             self._T.get(
                 "dlg_select_image_filter",
                 "Disk Images (*.iso *.dmg *.img *.bin *.raw);;All Files (*)",

src/lufus/gui/start_gui.py

@@ -51,6 +51,16 @@ def _show_root_warning() -> None:
 def launch_gui_with_usb_data() -> None:
     elevation_attempted = False
     if os.geteuid() != 0:
+        # Capture user context (XDG_DOWNLOAD_DIR path) before pkexec elevation
+        from lufus.user_paths import get_best_starting_dir, ENV_DOWNLOAD_DIR
+
+        try:
+            detected_path = get_best_starting_dir()
+            os.environ[ENV_DOWNLOAD_DIR] = detected_path
+            log.info("Captured user starting directory: %s", detected_path)
+        except Exception as e:
+            log.warning("Could not capture user starting directory: %s", e)
+
         _load_initial_theme()
         elevation_attempted = True
         elevate_privileges()

src/lufus/user_paths.py

@@ -0,0 +1,51 @@
+"""
+Utility for detecting user's XDG_DOWNLOAD_DIR across root elevation
+Falls back to ~/ if no XDG_DOWNLOAD_DIR is found
+Made it so it runs as fast as possible before exiting to free like 2-3 KB RAM if you are using an OptiPlex GX270 or smth
+"""
+
+import os
+from pathlib import Path
+from platformdirs import user_downloads_dir, user_documents_dir
+from lufus.lufus_logging import get_logger
+
+log = get_logger(__name__)
+
+# Environment variable used to tunnel the path through the root/pkexec barrier
+ENV_DOWNLOAD_DIR = "LUFUS_DOWNLOAD_DIR"
+
+
+def get_best_starting_dir() -> str:
+    """
+    Identify the best default dir for the file browser.
+
+    This function works in two steps:
+    1: Pre-elevation: Detects the real user's XDG_DOWNLOAD_DIR. If nothing is fonud, it falls back to ~/.
+    2: Post-elevation: Gets the path from the tunneled environment variable.
+
+    Returns:
+        str: An absolute path to a valid directory.
+    """
+    # 1. High Priority: Check if we've already tunneled the path via environment
+    tunneled = os.environ.get(ENV_DOWNLOAD_DIR)
+    if tunneled:
+        if os.path.isdir(tunneled):
+            log.debug("Using tunneled user path: %s", tunneled)
+            return tunneled
+        log.warning("Tunneled path %s is no longer a valid directory.", tunneled)
+
+    # 2. Medium Priority: Use platformdirs to find XDG standard paths
+    # This works best when called before elevation (geteuid != 0)
+    try:
+        # Standard XDG Downloads
+        dl_path = user_downloads_dir()
+        if dl_path and os.path.isdir(dl_path):
+            log.debug("Detected XDG Downloads directory: %s", dl_path)
+            return str(dl_path)
+    except Exception as e:
+        log.error("Failed to resolve XDG Downloads directory: %s", e)
+
+    # 3. Low Priority: Home directory fallback
+    home = str(Path.home())
+    log.debug("Falling back to home directory: %s", home)
+    return home

src/lufus/utils.py

@@ -27,13 +27,15 @@ def elevate_privileges() -> None:
             )
 
     # Preserve DISPLAY and XAUTHORITY for GUI apps under pkexec/sudo
+    # Now also takes the detected XDG_DOWNLOAD_DIR of /src/lufus/user_paths.py to put it into LUFUS_DOWNLOAD_DIR
     env_vars = [
         "DISPLAY",
         "XAUTHORITY",
         "XDG_RUNTIME_DIR",
         "WAYLAND_DISPLAY",
         "PYTHONPATH",
         "LUFUS_THEME",
+        "LUFUS_DOWNLOAD_DIR",
     ]
 
     cmd = ["pkexec", "env"]
@@ -47,7 +49,7 @@ def elevate_privileges() -> None:
         subprocess.run(cmd, check=True)
         sys.exit(0)
     except subprocess.CalledProcessError:
-        # User likely cancelled or pkexec failed
+        # User likely cancelled or pkexec failed/isn't installed
         pass
     except Exception as e:
         print(f"Elevation failed: {e}")

tests/test_user_paths.py

@@ -0,0 +1,59 @@
+import os
+import unittest
+from unittest.mock import patch, MagicMock
+from lufus.user_paths import get_best_starting_dir, ENV_DOWNLOAD_DIR
+
+
+class TestUserPaths(unittest.TestCase):
+    def setUp(self):
+        # Clear the var before each test
+        if ENV_DOWNLOAD_DIR in os.environ:
+            del os.environ[ENV_DOWNLOAD_DIR]
+
+    def test_get_best_starting_dir_with_env(self):
+        """Test that it prioritizes the environment variable if it points to a valid dir."""
+        test_path = "/tmp/lufus_test_dir"
+        os.makedirs(test_path, exist_ok=True)
+        try:
+            os.environ[ENV_DOWNLOAD_DIR] = test_path
+            self.assertEqual(get_best_starting_dir(), test_path)
+        finally:
+            if os.path.exists(test_path):
+                os.rmdir(test_path)
+
+    @patch("lufus.user_paths.user_downloads_dir")
+    @patch("os.path.isdir")
+    def test_get_best_starting_dir_with_xdg(self, mock_isdir, mock_downloads):
+        """Test that it uses XDG_DOWNLOAD_DIR if env is not set"""
+        mock_downloads.return_value = "/home/user/Downloads"
+        mock_isdir.side_effect = lambda p: p == "/home/user/Downloads"
+
+        self.assertEqual(get_best_starting_dir(), "/home/user/Downloads")
+
+    @patch("lufus.user_paths.user_downloads_dir")
+    @patch("os.path.isdir")
+    def test_get_best_starting_dir_with_custom_name(self, mock_isdir, mock_downloads):
+        """Test that it handles edge cases/translated names (like ~/Potato or ~/Téléchargements) (~/Potato is a great Downloads folder name btw)"""
+        custom_path = "/home/user/Téléchargements"
+        mock_downloads.return_value = custom_path
+        mock_isdir.side_effect = lambda p: p == custom_path
+
+        self.assertEqual(get_best_starting_dir(), custom_path)
+
+    @patch("lufus.user_paths.user_downloads_dir")
+    @patch("pathlib.Path.home")
+    @patch("os.path.isdir")
+    def test_get_best_starting_dir_fallback_to_home(self, mock_isdir, mock_home, mock_downloads):
+        """Test fallback to Home if Downloads is not found."""
+        mock_downloads.return_value = "/home/user/Downloads"
+        mock_home.return_value = MagicMock()
+        mock_home.return_value.__str__.return_value = "/home/user"
+
+        # Downloads does not exist
+        mock_isdir.return_value = False
+
+        self.assertEqual(get_best_starting_dir(), "/home/user")
+
+
+if __name__ == "__main__":
+    unittest.main()