[py] Fix WebKitGTK driver name check (#15046)

py: Fix WebKitGTK driver name.

Similar to WPEWebKit changes from 24d88d7, WebKitGTK does not
follow the simple capitalization scheme for the driver name.

This commit also changes the default `WebKitWebDriver` binary to the
first one in `PATH` through shutil.which, instead of just the binary
name.

(Note: The effort to move to `pathlib` instead of `shutil`[1] is more
related to shutil's functions that work on files and directories, like
copy and move, instead of `which`, which just searches the executable
paths for the given command.)

[1] https://discuss.python.org/t/incrementally-move-high-level-path-operations-from-shutil-to-pathlib/19208

Author: lauromoura

py/conftest.py

@@ -150,7 +150,8 @@ def fin():
             options = get_options("Firefox", request.config) or webdriver.FirefoxOptions()
             options.set_capability("moz:firefoxOptions", {})
             options.enable_downloads = True
-        if driver_class == "WebKitGTK":
+        if driver_class.lower() == "webkitgtk":
+            driver_class = "WebKitGTK"
             options = get_options(driver_class, request.config)
         if driver_class == "Edge":
             options = get_options(driver_class, request.config)

py/selenium/webdriver/webkitgtk/service.py

@@ -14,21 +14,22 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
+import shutil
 import warnings
 from typing import List
 from typing import Mapping
 from typing import Optional
 
 from selenium.webdriver.common import service
 
-DEFAULT_EXECUTABLE_PATH: str = "WebKitWebDriver"
+DEFAULT_EXECUTABLE_PATH: str = shutil.which("WebKitWebDriver")
 
 
 class Service(service.Service):
     """A Service class that is responsible for the starting and stopping of
-    `WPEWebDriver`.
+    `WebKitWebDriver`.
 
-    :param executable_path: install path of the WebKitWebDriver executable, defaults to `WebKitWebDriver`.
+    :param executable_path: install path of the WebKitWebDriver executable, defaults to the first `WebKitWebDriver` in `$PATH`.
     :param port: Port for the service to run on, defaults to 0 where the operating system will decide.
     :param service_args: (Optional) List of args to be passed to the subprocess when launching the executable.
     :param log_output: (Optional) File path for the file to be opened and passed as the subprocess stdout/stderr handler.