py: Ensure DRIVER_PATH_ENV_KEY defaults to string

[lauromoura]

User description

Description

Follow up to PR #14528, to avoid os.getenv raising TypeError in env_path when driver_path_env_key is not passed to Service constructor.

This happens, for example, with the WPEWebKit driver, which currently ignores driver_path_env_key, as the executable WPEWebDriver is usually available on $PATH (which is set either natively or through other test scripts).

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

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PR Type

Bug fix

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Description

• Added a parameter description for driver_path_env_key in the Service class docstring.
• Set the DRIVER_PATH_ENV_KEY to default to an empty string if not provided, preventing TypeError when os.getenv is called.
• This change ensures compatibility with drivers like WPEWebKit that do not use driver_path_env_key.

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Changes walkthrough 📝

	Relevant files
Bug fix	service.py Ensure DRIVER_PATH_ENV_KEY defaults to an empty string      py/selenium/webdriver/common/service.py Added a parameter description for driver_path_env_key. Set default value for DRIVER_PATH_ENV_KEY to an empty string. +2/-1

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[qodo-merge-pro]

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⏱️ Estimated effort to review: 1 🔵⚪⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Code Style Consider making DRIVER_PATH_ENV_KEY a class variable with default value instead of instance variable, since it represents a constant configuration value

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
General	Using None instead of an empty string better represents the absence of an environment variable key The empty string default for DRIVER_PATH_ENV_KEY could cause issues when checking environment variables. Consider using None as the default value to clearly indicate no environment key is specified. py/selenium/webdriver/common/service.py [79] -self.DRIVER_PATH_ENV_KEY = driver_path_env_key or "" +self.DRIVER_PATH_ENV_KEY = driver_path_env_key or None Apply this suggestion Suggestion importance[1-10]: 7 Why: Using None as a default value is more semantically correct for representing the absence of an environment variable key, making the code's intent clearer and preventing potential issues when checking environment variables.	7

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[lauromoura]

PR Code Suggestions ✨

Explore these optional code suggestions:
Category Suggestion Score
General
Using None instead of an empty string better represents the absence of an environment variable key

The empty string default for DRIVER_PATH_ENV_KEY could cause issues when checking environment variables. Consider using None as the default value to clearly indicate no environment key is specified.

py/selenium/webdriver/common/service.py [79]

-self.DRIVER_PATH_ENV_KEY = driver_path_env_key or ""
+self.DRIVER_PATH_ENV_KEY = driver_path_env_key or None

* [ ]  **Apply this suggestion**

Suggestion importance[1-10]: 7

Why: Using None as a default value is more semantically correct for representing the absence of an environment variable key, making the code's intent clearer and preventing potential issues when checking environment variables.
7

💡 Need additional feedback ? start a PR chat

Maybe, based on this feedback, it'd be better to replace "" with an if in env_path() to guard the call to os.getenv?

[Delta456]

It should default to an empty string imo so this can be merged!

[lauromoura]

Updated the patch to keep the recommendation of using "None" to indicate the absence of value.

[petrisorureche]

I think this change cause the following issue on Linux

File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/chrome/webdriver.py", line 45, in __init__ super().__init__( File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/chromium/webdriver.py", line 66, in __init__ super().__init__(command_executor=executor, options=options) File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__ self.start_session(capabilities) File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session response = self.execute(Command.NEW_SESSION, caps)["value"] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute self.error_handler.check_response(response) File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response raise exception_class(message, screen, stacktrace) selenium.common.exceptions.SessionNotCreatedException: Message: session not created: probably user data directory is already in use, please specify a unique value for --user-data-dir argument, or don't use --user-data-dir

[lauromoura]

I think this change causes the following issue on Linux:

File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/chrome/webdriver.py", line 45, in __init__
    super().__init__(
File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/chromium/webdriver.py", line 66, in __init__
    super().__init__(command_executor=executor, options=options)
File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 250, in __init__
    self.start_session(capabilities)
File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 342, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/webdriver.py", line 429, in execute
    self.error_handler.check_response(response)
File "/usr/local/lib/python3.12/site-packages/selenium/webdriver/remote/errorhandler.py", line 232, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.SessionNotCreatedException: Message: session not created: probably user data directory is already in use, please specify a unique value for --user-data-dir argument, or don't use --user-data-dir

(Formatted the trace for readability)

I'm not sure how this PR could cause this. Can you provide more information?