fix: eliminate async safety violations and migrate to pathlib (#697)

## ℹ️ Description
Eliminate all blocking I/O operations in async contexts and modernize
file path handling by migrating from os.path to pathlib.Path.

- Link to the related issue(s): #692 
- Get rid of the TODO in pyproject.toml
- The added debug logging will ease the troubleshooting for path related
issues.

## 📋 Changes Summary

- Enable ASYNC210, ASYNC230, ASYNC240, ASYNC250 Ruff rules
- Wrap blocking urllib.request.urlopen() in run_in_executor
- Wrap blocking file operations (open, write) in run_in_executor
- Replace blocking os.path calls with async helpers using
run_in_executor
- Replace blocking input() with await ainput()
- Migrate extract.py from os.path to pathlib.Path
- Use Path() constructor and / operator for path joining
- Use Path.mkdir(), Path.rename() in executor instead of os functions
- Create mockable _path_exists() and _path_is_dir() helpers
- Add debug logging for all file system operations

### ⚙️ Type of Change
Select the type(s) of change(s) included in this pull request:
- [X] 🐞 Bug fix (non-breaking change which fixes an issue)
- [ ] ✨ New feature (adds new functionality without breaking existing
usage)
- [ ] 💥 Breaking change (changes that might break existing user setups,
scripts, or configurations)


## ✅ Checklist
Before requesting a review, confirm the following:
- [X] I have reviewed my changes to ensure they meet the project's
standards.
- [X] I have tested my changes and ensured that all tests pass (`pdm run
test`).
- [X] I have formatted the code (`pdm run format`).
- [X] I have verified that linting passes (`pdm run lint`).
- [X] I have updated documentation where necessary.

By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Refactor**
  * Made user prompt non‑blocking to improve responsiveness.
* Converted filesystem/path handling and prefs I/O to async‑friendly
operations; moved blocking network and file work to background tasks.
* Added async file/path helpers and async port‑check before browser
connections.

* **Tests**
* Expanded unit tests for path helpers, image download success/failure,
prefs writing, and directory creation/renaming workflows.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

pyproject.toml

@@ -226,10 +226,6 @@ select = [
 ]
 ignore = [
   "ANN401",  # Dynamically typed expressions (typing.Any) are disallowed
-  "ASYNC210",  # TODO Async functions should not call blocking HTTP methods
-  "ASYNC230",  # TODO Async functions should not open files with blocking methods like `open`
-  "ASYNC240",  # TODO Async functions should not use os.path methods, use trio.Path or anyio.path
-  "ASYNC250",  # TODO Blocking call to input() in async context
   "COM812",  # Trailing comma missing
   "D1",  # Missing docstring in ...
   "D200",  # One-line docstring should fit on one line

src/kleinanzeigen_bot/__init__.py

@@ -937,7 +937,7 @@ class KleinanzeigenBot(WebScrapingMixin):
             LOG.warning("# Payment form detected! Please proceed with payment.")
             LOG.warning("############################################")
             await self.web_scroll_page_down()
-            input(_("Press a key to continue..."))
+            await ainput(_("Press a key to continue..."))
         except TimeoutError:
             pass
 
@@ -1108,7 +1108,7 @@ class KleinanzeigenBot(WebScrapingMixin):
                     # in some categories we need to go another dialog back
                     try:
                         await self.web_find(By.XPATH, '//dialog//button[contains(., "Andere Versandmethoden")]',
-                                            timeout=short_timeout)
+                                            timeout = short_timeout)
                     except TimeoutError:
                         await self.web_click(By.XPATH, '//dialog//button[contains(., "Zurück")]')
 

src/kleinanzeigen_bot/extract.py

@@ -1,18 +1,21 @@
 # SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
 # SPDX-License-Identifier: AGPL-3.0-or-later
 # SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
+import asyncio
 from gettext import gettext as _
 
-import json, mimetypes, os, re, shutil  # isort: skip
+import json, mimetypes, re, shutil  # isort: skip
+import urllib.error as urllib_error
 import urllib.request as urllib_request
 from datetime import datetime
+from pathlib import Path
 from typing import Any, Final
 
 from kleinanzeigen_bot.model.ad_model import ContactPartial
 
 from .model.ad_model import AdPartial
 from .model.config_model import Config
-from .utils import dicts, i18n, loggers, misc, reflect
+from .utils import dicts, files, i18n, loggers, misc, reflect
 from .utils.web_scraping_mixin import Browser, By, Element, WebScrapingMixin
 
 __all__ = [
@@ -44,23 +47,39 @@ class AdExtractor(WebScrapingMixin):
         """
 
         # create sub-directory for ad(s) to download (if necessary):
-        relative_directory = "downloaded-ads"
+        relative_directory = Path("downloaded-ads")
-        # make sure configured base directory exists
+        # make sure configured base directory exists (using exist_ok=True to avoid TOCTOU race)
-        if not os.path.exists(relative_directory) or not os.path.isdir(relative_directory):
+        await asyncio.get_running_loop().run_in_executor(None, lambda: relative_directory.mkdir(exist_ok = True))  # noqa: ASYNC240
-            os.mkdir(relative_directory)
+        LOG.info("Ensured ads directory exists at ./%s.", relative_directory)
-            LOG.info("Created ads directory at ./%s.", relative_directory)
 
         # Extract ad info and determine final directory path
         ad_cfg, final_dir = await self._extract_ad_page_info_with_directory_handling(
             relative_directory, ad_id
         )
 
-        # Save the ad configuration file
+        # Save the ad configuration file (offload to executor to avoid blocking the event loop)
-        ad_file_path = final_dir + "/" + f"ad_{ad_id}.yaml"
+        ad_file_path = str(Path(final_dir) / f"ad_{ad_id}.yaml")
-        dicts.save_dict(
+        header_string = "# yaml-language-server: $schema=https://raw.githubusercontent.com/Second-Hand-Friends/kleinanzeigen-bot/refs/heads/main/schemas/ad.schema.json"
-            ad_file_path,
+        await asyncio.get_running_loop().run_in_executor(
-            ad_cfg.model_dump(),
+            None,
-            header = "# yaml-language-server: $schema=https://raw.githubusercontent.com/Second-Hand-Friends/kleinanzeigen-bot/refs/heads/main/schemas/ad.schema.json")
+            lambda: dicts.save_dict(ad_file_path, ad_cfg.model_dump(), header = header_string)
+        )
+
+    @staticmethod
+    def _download_and_save_image_sync(url:str, directory:str, filename_prefix:str, img_nr:int) -> str | None:
+        try:
+            with urllib_request.urlopen(url) as response:  # noqa: S310 Audit URL open for permitted schemes.
+                content_type = response.info().get_content_type()
+                file_ending = mimetypes.guess_extension(content_type) or ""
+                # Use pathlib.Path for OS-agnostic path handling
+                img_path = Path(directory) / f"{filename_prefix}{img_nr}{file_ending}"
+                with open(img_path, "wb") as f:
+                    shutil.copyfileobj(response, f)
+                return str(img_path)
+        except (urllib_error.URLError, urllib_error.HTTPError, OSError, shutil.Error) as e:
+            # Narrow exception handling to expected network/filesystem errors
+            LOG.warning("Failed to download image %s: %s", url, e)
+            return None
 
     async def _download_images_from_ad_page(self, directory:str, ad_id:int) -> list[str]:
         """
@@ -85,19 +104,26 @@ class AdExtractor(WebScrapingMixin):
             img_nr = 1
             dl_counter = 0
 
+            loop = asyncio.get_running_loop()
+
             for img_element in images:
                 current_img_url = img_element.attrs["src"]  # URL of the image
                 if current_img_url is None:
                     continue
 
-                with urllib_request.urlopen(str(current_img_url)) as response:  # noqa: S310 Audit URL open for permitted schemes.
+                img_path = await loop.run_in_executor(
-                    content_type = response.info().get_content_type()
+                    None,
-                    file_ending = mimetypes.guess_extension(content_type)
+                    self._download_and_save_image_sync,
-                    img_path = f"{directory}/{img_fn_prefix}{img_nr}{file_ending}"
+                    str(current_img_url),
-                    with open(img_path, "wb") as f:
+                    directory,
-                        shutil.copyfileobj(response, f)
+                    img_fn_prefix,
+                    img_nr
+                )
+
+                if img_path:
                     dl_counter += 1
-                    img_paths.append(img_path.rsplit("/", maxsplit = 1)[-1])
+                    # Use pathlib.Path for OS-agnostic path handling
+                    img_paths.append(Path(img_path).name)
 
                 img_nr += 1
             LOG.info("Downloaded %s.", i18n.pluralize("image", dl_counter))
@@ -354,8 +380,8 @@ class AdExtractor(WebScrapingMixin):
         return ad_cfg
 
     async def _extract_ad_page_info_with_directory_handling(
-        self, relative_directory:str, ad_id:int
+        self, relative_directory:Path, ad_id:int
-    ) -> tuple[AdPartial, str]:
+    ) -> tuple[AdPartial, Path]:
         """
         Extracts ad information and handles directory creation/renaming.
 
@@ -373,32 +399,37 @@ class AdExtractor(WebScrapingMixin):
 
         # Determine the final directory path
         sanitized_title = misc.sanitize_folder_name(title, self.config.download.folder_name_max_length)
-        final_dir = os.path.join(relative_directory, f"ad_{ad_id}_{sanitized_title}")
+        final_dir = relative_directory / f"ad_{ad_id}_{sanitized_title}"
-        temp_dir = os.path.join(relative_directory, f"ad_{ad_id}")
+        temp_dir = relative_directory / f"ad_{ad_id}"
+
+        loop = asyncio.get_running_loop()
 
         # Handle existing directories
-        if os.path.exists(final_dir):
+        if await files.exists(final_dir):
             # If the folder with title already exists, delete it
             LOG.info("Deleting current folder of ad %s...", ad_id)
-            shutil.rmtree(final_dir)
+            LOG.debug("Removing directory tree: %s", final_dir)
+            await loop.run_in_executor(None, shutil.rmtree, str(final_dir))
 
-        if os.path.exists(temp_dir):
+        if await files.exists(temp_dir):
             if self.config.download.rename_existing_folders:
                 # Rename the old folder to the new name with title
                 LOG.info("Renaming folder from %s to %s for ad %s...",
-                        os.path.basename(temp_dir), os.path.basename(final_dir), ad_id)
+                        temp_dir.name, final_dir.name, ad_id)
-                os.rename(temp_dir, final_dir)
+                LOG.debug("Renaming: %s -> %s", temp_dir, final_dir)
+                await loop.run_in_executor(None, temp_dir.rename, final_dir)
             else:
                 # Use the existing folder without renaming
                 final_dir = temp_dir
                 LOG.info("Using existing folder for ad %s at %s.", ad_id, final_dir)
         else:
             # Create new directory with title
-            os.mkdir(final_dir)
+            LOG.debug("Creating new directory: %s", final_dir)
+            await loop.run_in_executor(None, final_dir.mkdir)
             LOG.info("New directory for ad created at %s.", final_dir)
 
         # Now extract complete ad info (including images) to the final directory
-        ad_cfg = await self._extract_ad_page_info(final_dir, ad_id)
+        ad_cfg = await self._extract_ad_page_info(str(final_dir), ad_id)
 
         return ad_cfg, final_dir
 

src/kleinanzeigen_bot/resources/translations.de.yaml

@@ -173,7 +173,10 @@ kleinanzeigen_bot/__init__.py:
 kleinanzeigen_bot/extract.py:
 #################################################
   download_ad:
-    "Created ads directory at ./%s.": "Verzeichnis für Anzeigen erstellt unter ./%s."
+    "Ensured ads directory exists at ./%s.": "Verzeichnis [%s] für Anzeige vorhanden."
+
+  _download_and_save_image_sync:
+    "Failed to download image %s: %s": "Fehler beim Herunterladen des Bildes %s: %s"
 
   _download_images_from_ad_page:
     "Found %s.": "%s gefunden."

src/kleinanzeigen_bot/utils/files.py

@@ -1,7 +1,8 @@
 # SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
 # SPDX-License-Identifier: AGPL-3.0-or-later
 # SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
-import os
+import asyncio, os  # isort: skip
+from pathlib import Path
 
 
 def abspath(relative_path:str, relative_to:str | None = None) -> str:
@@ -24,3 +25,23 @@ def abspath(relative_path:str, relative_to:str | None = None) -> str:
         base = os.path.dirname(base)
 
     return os.path.normpath(os.path.join(base, relative_path))
+
+
+async def exists(path:str | Path) -> bool:
+    """
+    Asynchronously check if a file or directory exists.
+
+    :param path: Path to check
+    :return: True if path exists, False otherwise
+    """
+    return await asyncio.get_running_loop().run_in_executor(None, Path(path).exists)
+
+
+async def is_dir(path:str | Path) -> bool:
+    """
+    Asynchronously check if a path is a directory.
+
+    :param path: Path to check
+    :return: True if path is a directory, False otherwise
+    """
+    return await asyncio.get_running_loop().run_in_executor(None, Path(path).is_dir)

src/kleinanzeigen_bot/utils/web_scraping_mixin.py

@@ -22,7 +22,7 @@ from nodriver.core.tab import Tab as Page
 from kleinanzeigen_bot.model.config_model import Config as BotConfig
 from kleinanzeigen_bot.model.config_model import TimeoutConfig
 
-from . import loggers, net
+from . import files, loggers, net
 from .chrome_version_detector import (
     ChromeVersionInfo,
     detect_chrome_version_from_binary,
@@ -100,6 +100,37 @@ class BrowserConfig:
         self.profile_name:str | None = None
 
 
+def _write_initial_prefs(prefs_file:str) -> None:
+    with open(prefs_file, "w", encoding = "UTF-8") as fd:
+        json.dump({
+            "credentials_enable_service": False,
+            "enable_do_not_track": True,
+            "google": {
+                "services": {
+                    "consented_to_sync": False
+                }
+            },
+            "profile": {
+                "default_content_setting_values": {
+                    "popups": 0,
+                    "notifications": 2  # 1 = allow, 2 = block browser notifications
+                },
+                "password_manager_enabled": False
+            },
+            "signin": {
+                "allowed": False
+            },
+            "translate_site_blacklist": [
+                "www.kleinanzeigen.de"
+            ],
+            "devtools": {
+                "preferences": {
+                    "currentDockState": '"bottom"'
+                }
+            }
+        }, fd)
+
+
 class WebScrapingMixin:
 
     def __init__(self) -> None:
@@ -174,7 +205,7 @@ class WebScrapingMixin:
         LOG.info("Creating Browser session...")
 
         if self.browser_config.binary_location:
-            ensure(os.path.exists(self.browser_config.binary_location), f"Specified browser binary [{self.browser_config.binary_location}] does not exist.")
+            ensure(await files.exists(self.browser_config.binary_location), f"Specified browser binary [{self.browser_config.binary_location}] does not exist.")
         else:
             self.browser_config.binary_location = self.get_compatible_browser()
         LOG.info(" -> Browser binary location: %s", self.browser_config.binary_location)
@@ -289,41 +320,14 @@ class WebScrapingMixin:
             profile_dir = os.path.join(cfg.user_data_dir, self.browser_config.profile_name or "Default")
             os.makedirs(profile_dir, exist_ok = True)
             prefs_file = os.path.join(profile_dir, "Preferences")
-            if not os.path.exists(prefs_file):
+            if not await files.exists(prefs_file):
                 LOG.info(" -> Setting chrome prefs [%s]...", prefs_file)
-                with open(prefs_file, "w", encoding = "UTF-8") as fd:
+                await asyncio.get_running_loop().run_in_executor(None, _write_initial_prefs, prefs_file)
-                    json.dump({
-                        "credentials_enable_service": False,
-                        "enable_do_not_track": True,
-                        "google": {
-                            "services": {
-                                "consented_to_sync": False
-                            }
-                        },
-                        "profile": {
-                            "default_content_setting_values": {
-                                "popups": 0,
-                                "notifications": 2  # 1 = allow, 2 = block browser notifications
-                            },
-                            "password_manager_enabled": False
-                        },
-                        "signin": {
-                            "allowed": False
-                        },
-                        "translate_site_blacklist": [
-                            "www.kleinanzeigen.de"
-                        ],
-                        "devtools": {
-                            "preferences": {
-                                "currentDockState": '"bottom"'
-                            }
-                        }
-                    }, fd)
 
         # load extensions
         for crx_extension in self.browser_config.extensions:
             LOG.info(" -> Adding Browser extension: [%s]", crx_extension)
-            ensure(os.path.exists(crx_extension), f"Configured extension-file [{crx_extension}] does not exist.")
+            ensure(await files.exists(crx_extension), f"Configured extension-file [{crx_extension}] does not exist.")
             cfg.add_extension(crx_extension)
 
         try:

tests/unit/test_extract.py

@@ -1,10 +1,12 @@
 # SPDX-FileCopyrightText: © Sebastian Thomschke and contributors
 # SPDX-License-Identifier: AGPL-3.0-or-later
 # SPDX-ArtifactOfProjectHomePage: https://github.com/Second-Hand-Friends/kleinanzeigen-bot/
-import json, os  # isort: skip
+import json  # isort: skip
 from gettext import gettext as _
+from pathlib import Path
 from typing import Any, TypedDict
 from unittest.mock import AsyncMock, MagicMock, call, patch
+from urllib.error import URLError
 
 import pytest
 
@@ -66,6 +68,124 @@ class TestAdExtractorBasics:
         """Test extraction of ad ID from different URL formats."""
         assert test_extractor.extract_ad_id_from_ad_url(url) == expected_id
 
+    @pytest.mark.asyncio
+    async def test_path_exists_helper(self, tmp_path:Path) -> None:
+        """Test files.exists helper function."""
+
+        from kleinanzeigen_bot.utils import files  # noqa: PLC0415
+
+        # Test with existing path
+        existing_file = tmp_path / "test.txt"
+        existing_file.write_text("test")
+        assert await files.exists(existing_file) is True
+        assert await files.exists(str(existing_file)) is True
+
+        # Test with non-existing path
+        non_existing = tmp_path / "nonexistent.txt"
+        assert await files.exists(non_existing) is False
+        assert await files.exists(str(non_existing)) is False
+
+    @pytest.mark.asyncio
+    async def test_path_is_dir_helper(self, tmp_path:Path) -> None:
+        """Test files.is_dir helper function."""
+
+        from kleinanzeigen_bot.utils import files  # noqa: PLC0415
+
+        # Test with directory
+        test_dir = tmp_path / "testdir"
+        test_dir.mkdir()
+        assert await files.is_dir(test_dir) is True
+        assert await files.is_dir(str(test_dir)) is True
+
+        # Test with file
+        test_file = tmp_path / "test.txt"
+        test_file.write_text("test")
+        assert await files.is_dir(test_file) is False
+        assert await files.is_dir(str(test_file)) is False
+
+        # Test with non-existing path
+        non_existing = tmp_path / "nonexistent"
+        assert await files.is_dir(non_existing) is False
+        assert await files.is_dir(str(non_existing)) is False
+
+    @pytest.mark.asyncio
+    async def test_exists_async_helper(self, tmp_path:Path) -> None:
+        """Test files.exists async helper function."""
+        from kleinanzeigen_bot.utils import files  # noqa: PLC0415
+
+        # Test with existing path
+        existing_file = tmp_path / "test.txt"
+        existing_file.write_text("test")
+        assert await files.exists(existing_file) is True
+        assert await files.exists(str(existing_file)) is True
+
+        # Test with non-existing path
+        non_existing = tmp_path / "nonexistent.txt"
+        assert await files.exists(non_existing) is False
+        assert await files.exists(str(non_existing)) is False
+
+    @pytest.mark.asyncio
+    async def test_isdir_async_helper(self, tmp_path:Path) -> None:
+        """Test files.is_dir async helper function."""
+        from kleinanzeigen_bot.utils import files  # noqa: PLC0415
+
+        # Test with directory
+        test_dir = tmp_path / "testdir"
+        test_dir.mkdir()
+        assert await files.is_dir(test_dir) is True
+        assert await files.is_dir(str(test_dir)) is True
+
+        # Test with file
+        test_file = tmp_path / "test.txt"
+        test_file.write_text("test")
+        assert await files.is_dir(test_file) is False
+        assert await files.is_dir(str(test_file)) is False
+
+        # Test with non-existing path
+        non_existing = tmp_path / "nonexistent"
+        assert await files.is_dir(non_existing) is False
+        assert await files.is_dir(str(non_existing)) is False
+
+    def test_download_and_save_image_sync_success(self, tmp_path:Path) -> None:
+        """Test _download_and_save_image_sync with successful download."""
+        from unittest.mock import MagicMock, mock_open  # noqa: PLC0415
+
+        test_dir = tmp_path / "images"
+        test_dir.mkdir()
+
+        # Mock urllib response
+        mock_response = MagicMock()
+        mock_response.info().get_content_type.return_value = "image/jpeg"
+        mock_response.__enter__ = MagicMock(return_value = mock_response)
+        mock_response.__exit__ = MagicMock(return_value = False)
+
+        with patch("kleinanzeigen_bot.extract.urllib_request.urlopen", return_value = mock_response), \
+                patch("kleinanzeigen_bot.extract.open", mock_open()), \
+                patch("kleinanzeigen_bot.extract.shutil.copyfileobj"):
+
+            result = AdExtractor._download_and_save_image_sync(
+                "http://example.com/image.jpg",
+                str(test_dir),
+                "test_",
+                1
+            )
+
+            assert result is not None
+            assert result.endswith((".jpe", ".jpeg", ".jpg"))
+            assert "test_1" in result
+
+    def test_download_and_save_image_sync_failure(self, tmp_path:Path) -> None:
+        """Test _download_and_save_image_sync with download failure."""
+        with patch("kleinanzeigen_bot.extract.urllib_request.urlopen", side_effect = URLError("Network error")):
+            result = AdExtractor._download_and_save_image_sync(
+                "http://example.com/image.jpg",
+                str(tmp_path),
+                "test_",
+                1
+            )
+
+            assert result is None
+
 
 class TestAdExtractorPricing:
     """Tests for pricing related functionality."""
@@ -865,84 +985,17 @@ class TestAdExtractorDownload:
         })
         return AdExtractor(browser_mock, config)
 
-    @pytest.mark.asyncio
-    async def test_download_ad_existing_directory(self, extractor:AdExtractor) -> None:
-        """Test downloading an ad when the directory already exists."""
-        with patch("os.path.exists") as mock_exists, \
-                patch("os.path.isdir") as mock_isdir, \
-                patch("os.makedirs") as mock_makedirs, \
-                patch("os.mkdir") as mock_mkdir, \
-                patch("os.rename") as mock_rename, \
-                patch("shutil.rmtree") as mock_rmtree, \
-                patch("kleinanzeigen_bot.extract.dicts.save_dict", autospec = True) as mock_save_dict, \
-                patch.object(extractor, "_extract_ad_page_info_with_directory_handling", new_callable = AsyncMock) as mock_extract_with_dir:
-
-            base_dir = "downloaded-ads"
-            final_dir = os.path.join(base_dir, "ad_12345_Test Advertisement Title")
-            yaml_path = os.path.join(final_dir, "ad_12345.yaml")
-
-            # Configure mocks for directory checks
-            existing_paths = {base_dir, final_dir}  # Final directory with title exists
-            mock_exists.side_effect = lambda path: path in existing_paths
-            mock_isdir.side_effect = lambda path: path == base_dir
-
-            # Mock the new method that handles directory creation and extraction
-            mock_extract_with_dir.return_value = (
-                AdPartial.model_validate({
-                    "title": "Test Advertisement Title",
-                    "description": "Test Description",
-                    "category": "Dienstleistungen",
-                    "price": 100,
-                    "images": [],
-                    "contact": {
-                        "name": "Test User",
-                        "street": "Test Street 123",
-                        "zipcode": "12345",
-                        "location": "Test City"
-                    }
-                }),
-                final_dir
-            )
-
-            await extractor.download_ad(12345)
-
-            # Verify the correct functions were called
-            mock_extract_with_dir.assert_called_once()
-            # Directory handling is now done inside _extract_ad_page_info_with_directory_handling
-            # so we don't expect rmtree/mkdir to be called directly in download_ad
-            mock_rmtree.assert_not_called()  # Directory handling is done internally
-            mock_mkdir.assert_not_called()  # Directory handling is done internally
-            mock_makedirs.assert_not_called()  # Directory already exists
-            mock_rename.assert_not_called()  # No renaming needed
-
-            # Get the actual call arguments
-            actual_call = mock_save_dict.call_args
-            assert actual_call is not None
-            actual_path = actual_call[0][0].replace("/", os.path.sep)
-            assert actual_path == yaml_path
-            assert actual_call[0][1] == mock_extract_with_dir.return_value[0].model_dump()
-
     @pytest.mark.asyncio
     async def test_download_ad(self, extractor:AdExtractor) -> None:
-        """Test downloading an entire ad."""
+        """Test downloading an ad - directory creation and saving ad data."""
-        with patch("os.path.exists") as mock_exists, \
+        with patch("pathlib.Path.mkdir"), \
-                patch("os.path.isdir") as mock_isdir, \
-                patch("os.makedirs") as mock_makedirs, \
-                patch("os.mkdir") as mock_mkdir, \
-                patch("os.rename") as mock_rename, \
-                patch("shutil.rmtree") as mock_rmtree, \
                 patch("kleinanzeigen_bot.extract.dicts.save_dict", autospec = True) as mock_save_dict, \
                 patch.object(extractor, "_extract_ad_page_info_with_directory_handling", new_callable = AsyncMock) as mock_extract_with_dir:
 
-            base_dir = "downloaded-ads"
+            # Use Path for OS-agnostic path handling
-            final_dir = os.path.join(base_dir, "ad_12345_Test Advertisement Title")
+            final_dir = Path("downloaded-ads") / "ad_12345_Test Advertisement Title"
-            yaml_path = os.path.join(final_dir, "ad_12345.yaml")
+            yaml_path = final_dir / "ad_12345.yaml"
 
-            # Configure mocks for directory checks
-            mock_exists.return_value = False
-            mock_isdir.return_value = False
-
-            # Mock the new method that handles directory creation and extraction
             mock_extract_with_dir.return_value = (
                 AdPartial.model_validate({
                     "title": "Test Advertisement Title",
@@ -957,140 +1010,18 @@ class TestAdExtractorDownload:
                         "location": "Test City"
                     }
                 }),
-                final_dir
+                str(final_dir)
             )
 
             await extractor.download_ad(12345)
 
-            # Verify the correct functions were called
+            # Verify observable behavior: extraction and save were called
             mock_extract_with_dir.assert_called_once()
-            # Directory handling is now done inside _extract_ad_page_info_with_directory_handling
+            mock_save_dict.assert_called_once()
-            mock_rmtree.assert_not_called()  # Directory handling is done internally
-            mock_mkdir.assert_has_calls([call(base_dir)])  # Only base directory creation
-            mock_makedirs.assert_not_called()  # Using mkdir instead
-            mock_rename.assert_not_called()  # No renaming needed
 
-            # Get the actual call arguments
+            # Verify saved to correct location with correct data
             actual_call = mock_save_dict.call_args
-            assert actual_call is not None
+            actual_path = Path(actual_call[0][0])
-            actual_path = actual_call[0][0].replace("/", os.path.sep)
-            assert actual_path == yaml_path
-            assert actual_call[0][1] == mock_extract_with_dir.return_value[0].model_dump()
-
-    @pytest.mark.asyncio
-    async def test_download_ad_use_existing_folder(self, extractor:AdExtractor) -> None:
-        """Test downloading an ad when an old folder without title exists (default behavior)."""
-        with patch("os.path.exists") as mock_exists, \
-                patch("os.path.isdir") as mock_isdir, \
-                patch("os.makedirs") as mock_makedirs, \
-                patch("os.mkdir") as mock_mkdir, \
-                patch("os.rename") as mock_rename, \
-                patch("shutil.rmtree") as mock_rmtree, \
-                patch("kleinanzeigen_bot.extract.dicts.save_dict", autospec = True) as mock_save_dict, \
-                patch.object(extractor, "_extract_ad_page_info_with_directory_handling", new_callable = AsyncMock) as mock_extract_with_dir:
-
-            base_dir = "downloaded-ads"
-            temp_dir = os.path.join(base_dir, "ad_12345")
-            yaml_path = os.path.join(temp_dir, "ad_12345.yaml")
-
-            # Configure mocks for directory checks
-            # Base directory exists, temp directory exists
-            existing_paths = {base_dir, temp_dir}
-            mock_exists.side_effect = lambda path: path in existing_paths
-            mock_isdir.side_effect = lambda path: path == base_dir
-
-            # Mock the new method that handles directory creation and extraction
-            mock_extract_with_dir.return_value = (
-                AdPartial.model_validate({
-                    "title": "Test Advertisement Title",
-                    "description": "Test Description",
-                    "category": "Dienstleistungen",
-                    "price": 100,
-                    "images": [],
-                    "contact": {
-                        "name": "Test User",
-                        "street": "Test Street 123",
-                        "zipcode": "12345",
-                        "location": "Test City"
-                    }
-                }),
-                temp_dir  # Use existing temp directory
-            )
-
-            await extractor.download_ad(12345)
-
-            # Verify the correct functions were called
-            mock_extract_with_dir.assert_called_once()
-            mock_rmtree.assert_not_called()  # No directory to remove
-            mock_mkdir.assert_not_called()  # Base directory already exists
-            mock_makedirs.assert_not_called()  # Using mkdir instead
-            mock_rename.assert_not_called()  # No renaming (default behavior)
-
-            # Get the actual call arguments
-            actual_call = mock_save_dict.call_args
-            assert actual_call is not None
-            actual_path = actual_call[0][0].replace("/", os.path.sep)
-            assert actual_path == yaml_path
-            assert actual_call[0][1] == mock_extract_with_dir.return_value[0].model_dump()
-
-    @pytest.mark.asyncio
-    async def test_download_ad_rename_existing_folder_when_enabled(self, extractor:AdExtractor) -> None:
-        """Test downloading an ad when an old folder without title exists and renaming is enabled."""
-        # Enable renaming in config
-        extractor.config.download.rename_existing_folders = True
-
-        with patch("os.path.exists") as mock_exists, \
-                patch("os.path.isdir") as mock_isdir, \
-                patch("os.makedirs") as mock_makedirs, \
-                patch("os.mkdir") as mock_mkdir, \
-                patch("os.rename") as mock_rename, \
-                patch("shutil.rmtree") as mock_rmtree, \
-                patch("kleinanzeigen_bot.extract.dicts.save_dict", autospec = True) as mock_save_dict, \
-                patch.object(extractor, "_extract_ad_page_info_with_directory_handling", new_callable = AsyncMock) as mock_extract_with_dir:
-
-            base_dir = "downloaded-ads"
-            temp_dir = os.path.join(base_dir, "ad_12345")
-            final_dir = os.path.join(base_dir, "ad_12345_Test Advertisement Title")
-            yaml_path = os.path.join(final_dir, "ad_12345.yaml")
-
-            # Configure mocks for directory checks
-            # Base directory exists, temp directory exists, final directory doesn't exist
-            existing_paths = {base_dir, temp_dir}
-            mock_exists.side_effect = lambda path: path in existing_paths
-            mock_isdir.side_effect = lambda path: path == base_dir
-
-            # Mock the new method that handles directory creation and extraction
-            mock_extract_with_dir.return_value = (
-                AdPartial.model_validate({
-                    "title": "Test Advertisement Title",
-                    "description": "Test Description",
-                    "category": "Dienstleistungen",
-                    "price": 100,
-                    "images": [],
-                    "contact": {
-                        "name": "Test User",
-                        "street": "Test Street 123",
-                        "zipcode": "12345",
-                        "location": "Test City"
-                    }
-                }),
-                final_dir
-            )
-
-            await extractor.download_ad(12345)
-
-            # Verify the correct functions were called
-            mock_extract_with_dir.assert_called_once()  # Extract to final directory
-            # Directory handling (including renaming) is now done inside _extract_ad_page_info_with_directory_handling
-            mock_rmtree.assert_not_called()  # Directory handling is done internally
-            mock_mkdir.assert_not_called()  # Directory handling is done internally
-            mock_makedirs.assert_not_called()  # Using mkdir instead
-            mock_rename.assert_not_called()  # Directory handling is done internally
-
-            # Get the actual call arguments
-            actual_call = mock_save_dict.call_args
-            assert actual_call is not None
-            actual_path = actual_call[0][0].replace("/", os.path.sep)
             assert actual_path == yaml_path
             assert actual_call[0][1] == mock_extract_with_dir.return_value[0].model_dump()
 
@@ -1101,3 +1032,196 @@ class TestAdExtractorDownload:
         with patch.object(extractor, "web_find", new_callable = AsyncMock, side_effect = TimeoutError):
             image_paths = await extractor._download_images_from_ad_page("/some/dir", 12345)
             assert len(image_paths) == 0
+
+    @pytest.mark.asyncio
+    # pylint: disable=protected-access
+    async def test_download_images_with_none_url(self, extractor:AdExtractor) -> None:
+        """Test image download when some images have None as src attribute."""
+        image_box_mock = MagicMock()
+
+        # Create image elements - one with valid src, one with None src
+        img_with_url = MagicMock()
+        img_with_url.attrs = {"src": "http://example.com/valid_image.jpg"}
+
+        img_without_url = MagicMock()
+        img_without_url.attrs = {"src": None}
+
+        with patch.object(extractor, "web_find", new_callable = AsyncMock, return_value = image_box_mock), \
+                patch.object(extractor, "web_find_all", new_callable = AsyncMock, return_value = [img_with_url, img_without_url]), \
+                patch.object(AdExtractor, "_download_and_save_image_sync", return_value = "/some/dir/ad_12345__img1.jpg"):
+
+            image_paths = await extractor._download_images_from_ad_page("/some/dir", 12345)
+
+            # Should only download the one valid image (skip the None)
+            assert len(image_paths) == 1
+            assert image_paths[0] == "ad_12345__img1.jpg"
+
+    @pytest.mark.asyncio
+    # pylint: disable=protected-access
+    async def test_extract_ad_page_info_with_directory_handling_final_dir_exists(
+        self, extractor:AdExtractor, tmp_path:Path
+    ) -> None:
+        """Test directory handling when final_dir already exists - it should be deleted."""
+        base_dir = tmp_path / "downloaded-ads"
+        base_dir.mkdir()
+
+        # Create the final directory that should be deleted
+        final_dir = base_dir / "ad_12345_Test Title"
+        final_dir.mkdir()
+        old_file = final_dir / "old_file.txt"
+        old_file.write_text("old content")
+
+        # Mock the page
+        page_mock = MagicMock()
+        page_mock.url = "https://www.kleinanzeigen.de/s-anzeige/test/12345"
+        extractor.page = page_mock
+
+        with patch.object(extractor, "web_text", new_callable = AsyncMock, side_effect = [
+                "Test Title",  # Title extraction
+                "Test Title",  # Second title call for full extraction
+                "Description text",  # Description
+                "03.02.2025"  # Creation date
+            ]), \
+                patch.object(extractor, "web_execute", new_callable = AsyncMock, return_value = {
+                    "universalAnalyticsOpts": {
+                        "dimensions": {
+                            "dimension92": "",
+                            "dimension108": ""
+                        }
+                    }
+                }), \
+                patch.object(extractor, "_extract_category_from_ad_page", new_callable = AsyncMock, return_value = "160"), \
+                patch.object(extractor, "_extract_special_attributes_from_ad_page", new_callable = AsyncMock, return_value = {}), \
+                patch.object(extractor, "_extract_pricing_info_from_ad_page", new_callable = AsyncMock, return_value = (None, "NOT_APPLICABLE")), \
+                patch.object(extractor, "_extract_shipping_info_from_ad_page", new_callable = AsyncMock, return_value = ("NOT_APPLICABLE", None, None)), \
+                patch.object(extractor, "_extract_sell_directly_from_ad_page", new_callable = AsyncMock, return_value = False), \
+                patch.object(extractor, "_download_images_from_ad_page", new_callable = AsyncMock, return_value = []), \
+                patch.object(extractor, "_extract_contact_from_ad_page", new_callable = AsyncMock, return_value = ContactPartial(
+                    name = "Test", zipcode = "12345", location = "Berlin"
+                )):
+
+            ad_cfg, result_dir = await extractor._extract_ad_page_info_with_directory_handling(
+                base_dir, 12345
+            )
+
+            # Verify the old directory was deleted and recreated
+            assert result_dir == final_dir
+            assert result_dir.exists()
+            assert not old_file.exists()  # Old file should be gone
+            assert ad_cfg.title == "Test Title"
+
+    @pytest.mark.asyncio
+    # pylint: disable=protected-access
+    async def test_extract_ad_page_info_with_directory_handling_rename_enabled(
+        self, extractor:AdExtractor, tmp_path:Path
+    ) -> None:
+        """Test directory handling when temp_dir exists and rename_existing_folders is True."""
+        base_dir = tmp_path / "downloaded-ads"
+        base_dir.mkdir()
+
+        # Create the temp directory (without title)
+        temp_dir = base_dir / "ad_12345"
+        temp_dir.mkdir()
+        existing_file = temp_dir / "existing_image.jpg"
+        existing_file.write_text("existing image data")
+
+        # Enable rename_existing_folders in config
+        extractor.config.download.rename_existing_folders = True
+
+        # Mock the page
+        page_mock = MagicMock()
+        page_mock.url = "https://www.kleinanzeigen.de/s-anzeige/test/12345"
+        extractor.page = page_mock
+
+        with patch.object(extractor, "web_text", new_callable = AsyncMock, side_effect = [
+                "Test Title",  # Title extraction
+                "Test Title",  # Second title call for full extraction
+                "Description text",  # Description
+                "03.02.2025"  # Creation date
+            ]), \
+                patch.object(extractor, "web_execute", new_callable = AsyncMock, return_value = {
+                    "universalAnalyticsOpts": {
+                        "dimensions": {
+                            "dimension92": "",
+                            "dimension108": ""
+                        }
+                    }
+                }), \
+                patch.object(extractor, "_extract_category_from_ad_page", new_callable = AsyncMock, return_value = "160"), \
+                patch.object(extractor, "_extract_special_attributes_from_ad_page", new_callable = AsyncMock, return_value = {}), \
+                patch.object(extractor, "_extract_pricing_info_from_ad_page", new_callable = AsyncMock, return_value = (None, "NOT_APPLICABLE")), \
+                patch.object(extractor, "_extract_shipping_info_from_ad_page", new_callable = AsyncMock, return_value = ("NOT_APPLICABLE", None, None)), \
+                patch.object(extractor, "_extract_sell_directly_from_ad_page", new_callable = AsyncMock, return_value = False), \
+                patch.object(extractor, "_download_images_from_ad_page", new_callable = AsyncMock, return_value = []), \
+                patch.object(extractor, "_extract_contact_from_ad_page", new_callable = AsyncMock, return_value = ContactPartial(
+                    name = "Test", zipcode = "12345", location = "Berlin"
+                )):
+
+            ad_cfg, result_dir = await extractor._extract_ad_page_info_with_directory_handling(
+                base_dir, 12345
+            )
+
+            # Verify the directory was renamed from temp_dir to final_dir
+            final_dir = base_dir / "ad_12345_Test Title"
+            assert result_dir == final_dir
+            assert result_dir.exists()
+            assert not temp_dir.exists()  # Old temp dir should be gone
+            assert (result_dir / "existing_image.jpg").exists()  # File should be preserved
+            assert ad_cfg.title == "Test Title"
+
+    @pytest.mark.asyncio
+    # pylint: disable=protected-access
+    async def test_extract_ad_page_info_with_directory_handling_use_existing(
+        self, extractor:AdExtractor, tmp_path:Path
+    ) -> None:
+        """Test directory handling when temp_dir exists and rename_existing_folders is False (default)."""
+        base_dir = tmp_path / "downloaded-ads"
+        base_dir.mkdir()
+
+        # Create the temp directory (without title)
+        temp_dir = base_dir / "ad_12345"
+        temp_dir.mkdir()
+        existing_file = temp_dir / "existing_image.jpg"
+        existing_file.write_text("existing image data")
+
+        # Ensure rename_existing_folders is False (default)
+        extractor.config.download.rename_existing_folders = False
+
+        # Mock the page
+        page_mock = MagicMock()
+        page_mock.url = "https://www.kleinanzeigen.de/s-anzeige/test/12345"
+        extractor.page = page_mock
+
+        with patch.object(extractor, "web_text", new_callable = AsyncMock, side_effect = [
+                "Test Title",  # Title extraction
+                "Test Title",  # Second title call for full extraction
+                "Description text",  # Description
+                "03.02.2025"  # Creation date
+            ]), \
+                patch.object(extractor, "web_execute", new_callable = AsyncMock, return_value = {
+                    "universalAnalyticsOpts": {
+                        "dimensions": {
+                            "dimension92": "",
+                            "dimension108": ""
+                        }
+                    }
+                }), \
+                patch.object(extractor, "_extract_category_from_ad_page", new_callable = AsyncMock, return_value = "160"), \
+                patch.object(extractor, "_extract_special_attributes_from_ad_page", new_callable = AsyncMock, return_value = {}), \
+                patch.object(extractor, "_extract_pricing_info_from_ad_page", new_callable = AsyncMock, return_value = (None, "NOT_APPLICABLE")), \
+                patch.object(extractor, "_extract_shipping_info_from_ad_page", new_callable = AsyncMock, return_value = ("NOT_APPLICABLE", None, None)), \
+                patch.object(extractor, "_extract_sell_directly_from_ad_page", new_callable = AsyncMock, return_value = False), \
+                patch.object(extractor, "_download_images_from_ad_page", new_callable = AsyncMock, return_value = []), \
+                patch.object(extractor, "_extract_contact_from_ad_page", new_callable = AsyncMock, return_value = ContactPartial(
+                    name = "Test", zipcode = "12345", location = "Berlin"
+                )):
+
+            ad_cfg, result_dir = await extractor._extract_ad_page_info_with_directory_handling(
+                base_dir, 12345
+            )
+
+            # Verify the existing temp_dir was used (not renamed)
+            assert result_dir == temp_dir
+            assert result_dir.exists()
+            assert (result_dir / "existing_image.jpg").exists()  # File should be preserved
+            assert ad_cfg.title == "Test Title"

tests/unit/test_init.py

@@ -641,12 +641,11 @@ class TestKleinanzeigenBotCommands:
     async def test_verify_command(self, test_bot:KleinanzeigenBot, tmp_path:Any) -> None:
         """Test verify command with minimal config."""
         config_path = Path(tmp_path) / "config.yaml"
-        with open(config_path, "w", encoding = "utf-8") as f:
+        config_path.write_text("""
-            f.write("""
 login:
     username: test
     password: test
-""")
+""", encoding = "utf-8")
         test_bot.config_file_path = str(config_path)
         await test_bot.run(["script.py", "verify"])
         assert test_bot.config.login.username == "test"

tests/unit/test_web_scraping_mixin.py

@@ -25,7 +25,7 @@ from nodriver.core.element import Element
 from nodriver.core.tab import Tab as Page
 
 from kleinanzeigen_bot.model.config_model import Config
-from kleinanzeigen_bot.utils import loggers
+from kleinanzeigen_bot.utils import files, loggers
 from kleinanzeigen_bot.utils.web_scraping_mixin import By, Is, WebScrapingMixin, _is_admin  # noqa: PLC2701
 
 
@@ -95,6 +95,30 @@ def web_scraper(mock_browser:AsyncMock, mock_page:TrulyAwaitableMockPage) -> Web
     return scraper
 
 
+def test_write_initial_prefs(tmp_path:Path) -> None:
+    """Test _write_initial_prefs helper function."""
+    from kleinanzeigen_bot.utils.web_scraping_mixin import _write_initial_prefs  # noqa: PLC0415, PLC2701
+
+    prefs_file = tmp_path / "Preferences"
+    _write_initial_prefs(str(prefs_file))
+
+    # Verify file was created
+    assert prefs_file.exists()
+
+    # Verify content is valid JSON with expected structure
+    with open(prefs_file, encoding = "UTF-8") as f:
+        prefs = json.load(f)
+
+    assert prefs["credentials_enable_service"] is False
+    assert prefs["enable_do_not_track"] is True
+    assert prefs["google"]["services"]["consented_to_sync"] is False
+    assert prefs["profile"]["password_manager_enabled"] is False
+    assert prefs["profile"]["default_content_setting_values"]["notifications"] == 2
+    assert prefs["signin"]["allowed"] is False
+    assert "www.kleinanzeigen.de" in prefs["translate_site_blacklist"]
+    assert prefs["devtools"]["preferences"]["currentDockState"] == '"bottom"'
+
+
 class TestWebScrapingErrorHandling:
     """Test error handling scenarios in WebScrapingMixin."""
 
@@ -728,7 +752,7 @@ class TestWebScrapingBrowserConfiguration:
         chrome_path = "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome"
         real_exists = os.path.exists
 
-        def mock_exists(path:str) -> bool:
+        def mock_exists_sync(path:str) -> bool:
             # Handle all browser paths
             if path in {
                 # Linux paths
@@ -754,7 +778,12 @@ class TestWebScrapingBrowserConfiguration:
             if "Preferences" in str(path) and str(tmp_path) in str(path):
                 return real_exists(path)
             return False
-        monkeypatch.setattr(os.path, "exists", mock_exists)
+
+        async def mock_exists_async(path:str | Path) -> bool:
+            return mock_exists_sync(str(path))
+
+        monkeypatch.setattr(os.path, "exists", mock_exists_sync)
+        monkeypatch.setattr(files, "exists", mock_exists_async)
 
         # Create test profile directory
         profile_dir = tmp_path / "Default"
@@ -762,8 +791,7 @@ class TestWebScrapingBrowserConfiguration:
         prefs_file = profile_dir / "Preferences"
 
         # Test with existing preferences file
-        with open(prefs_file, "w", encoding = "UTF-8") as f:
+        prefs_file.write_text(json.dumps({"existing": "prefs"}), encoding = "UTF-8")
-            json.dump({"existing": "prefs"}, f)
 
         scraper = WebScrapingMixin()
         scraper.browser_config.user_data_dir = str(tmp_path)
@@ -771,8 +799,7 @@ class TestWebScrapingBrowserConfiguration:
         await scraper.create_browser_session()
 
         # Verify preferences file was not overwritten
-        with open(prefs_file, "r", encoding = "UTF-8") as f:
+        prefs = json.loads(prefs_file.read_text(encoding = "UTF-8"))
-            prefs = json.load(f)
         assert prefs["existing"] == "prefs"
 
         # Test with missing preferences file
@@ -780,8 +807,7 @@ class TestWebScrapingBrowserConfiguration:
         await scraper.create_browser_session()
 
         # Verify new preferences file was created with correct settings
-        with open(prefs_file, "r", encoding = "UTF-8") as f:
+        prefs = json.loads(prefs_file.read_text(encoding = "UTF-8"))
-            prefs = json.load(f)
         assert prefs["credentials_enable_service"] is False
         assert prefs["enable_do_not_track"] is True
         assert prefs["profile"]["password_manager_enabled"] is False
@@ -815,6 +841,10 @@ class TestWebScrapingBrowserConfiguration:
         # Mock os.path.exists to return True for both Chrome and Edge paths
         monkeypatch.setattr(os.path, "exists", lambda p: p in {"/usr/bin/chrome", "/usr/bin/edge"})
 
+        async def mock_exists_async(path:str | Path) -> bool:
+            return str(path) in {"/usr/bin/chrome", "/usr/bin/edge"}
+        monkeypatch.setattr(files, "exists", mock_exists_async)
+
         # Test with custom arguments
         scraper = WebScrapingMixin()
         scraper.browser_config.arguments = ["--custom-arg=value", "--another-arg"]
@@ -875,27 +905,41 @@ class TestWebScrapingBrowserConfiguration:
         # Mock Config class
         monkeypatch.setattr(nodriver.core.config, "Config", DummyConfig)  # type: ignore[unused-ignore,reportAttributeAccessIssue,attr-defined]
 
-        # Mock os.path.exists to return True for browser binaries and extension files, real_exists for others
+        # Mock files.exists and files.is_dir to return appropriate values
-        real_exists = os.path.exists
+        async def mock_exists(path:str | Path) -> bool:
-        monkeypatch.setattr(
+            path_str = str(path)
-            os.path,
+            # Resolve real paths to handle symlinks (e.g., /var -> /private/var on macOS)
-            "exists",
+            real_path = str(Path(path_str).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
-            lambda p: p in {"/usr/bin/chrome", "/usr/bin/edge", str(ext1), str(ext2)} or real_exists(p),
+            real_ext1 = str(Path(ext1).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
-        )
+            real_ext2 = str(Path(ext2).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
+            return path_str in {"/usr/bin/chrome", "/usr/bin/edge"} or real_path in {real_ext1, real_ext2} or os.path.exists(path_str)  # noqa: ASYNC240
+
+        async def mock_is_dir(path:str | Path) -> bool:
+            path_str = str(path)
+            # Resolve real paths to handle symlinks
+            real_path = str(Path(path_str).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
+            real_ext1 = str(Path(ext1).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
+            real_ext2 = str(Path(ext2).resolve())  # noqa: ASYNC240 Test mock, runs synchronously
+            # Nodriver extracts CRX files to temp directories, so they appear as directories
+            if real_path in {real_ext1, real_ext2}:
+                return True
+            return Path(path_str).is_dir()  # noqa: ASYNC240 Test mock, runs synchronously
+
+        monkeypatch.setattr(files, "exists", mock_exists)
+        monkeypatch.setattr(files, "is_dir", mock_is_dir)
 
         # Test extension loading
         scraper = WebScrapingMixin()
         scraper.browser_config.extensions = [str(ext1), str(ext2)]
         scraper.browser_config.binary_location = "/usr/bin/chrome"
-        # Removed monkeypatch for os.path.exists so extension files are detected
         await scraper.create_browser_session()
 
         # Verify extensions were loaded
         config = _nodriver_start_mock().call_args[0][0]
         assert len(config._extensions) == 2
         for ext_path in config._extensions:
-            assert os.path.exists(ext_path)
+            assert await files.exists(ext_path)
-            assert os.path.isdir(ext_path)
+            assert await files.is_dir(ext_path)
 
         # Test with non-existent extension
         scraper.browser_config.extensions = ["non_existent.crx"]
@@ -976,8 +1020,7 @@ class TestWebScrapingBrowserConfiguration:
         scraper.browser_config.user_data_dir = str(tmp_path)
         scraper.browser_config.profile_name = "Default"
         await scraper.create_browser_session()
-        with open(state_file, "w", encoding = "utf-8") as f:
+        state_file.write_text('{"foo": "bar"}', encoding = "utf-8")
-            f.write('{"foo": "bar"}')
         scraper.browser._process_pid = 12345
         scraper.browser.stop = MagicMock()
         with patch("psutil.Process") as mock_proc:
@@ -989,8 +1032,7 @@ class TestWebScrapingBrowserConfiguration:
         scraper2.browser_config.user_data_dir = str(tmp_path)
         scraper2.browser_config.profile_name = "Default"
         await scraper2.create_browser_session()
-        with open(state_file, "r", encoding = "utf-8") as f:
+        data = state_file.read_text(encoding = "utf-8")
-            data = f.read()
         assert data == '{"foo": "bar"}'
         scraper2.browser._process_pid = 12346
         scraper2.browser.stop = MagicMock()
@@ -1814,6 +1856,7 @@ class TestWebScrapingMixinPortRetry:
     ) -> None:
         """Test error handling when browser connection fails."""
         with patch("os.path.exists", return_value = True), \
+                patch("kleinanzeigen_bot.utils.web_scraping_mixin.files.exists", AsyncMock(return_value = True)), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.net.is_port_open", return_value = True), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.start", side_effect = Exception("Failed to connect as root user")), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.Config") as mock_config_class:
@@ -1833,6 +1876,7 @@ class TestWebScrapingMixinPortRetry:
     ) -> None:
         """Test error handling when browser connection fails with non-root error."""
         with patch("os.path.exists", return_value = True), \
+                patch("kleinanzeigen_bot.utils.web_scraping_mixin.files.exists", AsyncMock(return_value = True)), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.net.is_port_open", return_value = True), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.start", side_effect = Exception("Connection timeout")), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.Config") as mock_config_class:
@@ -1860,6 +1904,7 @@ class TestWebScrapingMixinPortRetry:
     ) -> None:
         """Test error handling when browser startup fails with root error."""
         with patch("os.path.exists", return_value = True), \
+                patch("kleinanzeigen_bot.utils.web_scraping_mixin.files.exists", AsyncMock(return_value = True)), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.start", side_effect = Exception("Failed to start as root user")), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.Config") as mock_config_class:
 
@@ -1878,6 +1923,7 @@ class TestWebScrapingMixinPortRetry:
     ) -> None:
         """Test error handling when browser startup fails with non-root error."""
         with patch("os.path.exists", return_value = True), \
+                patch("kleinanzeigen_bot.utils.web_scraping_mixin.files.exists", AsyncMock(return_value = True)), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.start", side_effect = Exception("Browser binary not found")), \
                 patch("kleinanzeigen_bot.utils.web_scraping_mixin.nodriver.Config") as mock_config_class: