Identifying the Current Pytest Test

A Guide for QA Automation Engineers

August 27, 2024 by cryan.com

In the realm of Python testing with Pytest, understanding the currently executing test can be a game-changer, especially when aiming for code reusability and efficiency. This blog post will delve into the techniques that allow you to identify the specific Pytest test being run, empowering you to write more modular and adaptable automation scripts.

Leveraging os.environ.get('PYTEST_CURRENT_TEST')

One of the most straightforward methods to determine the current test involves utilizing the os.environ.get('PYTEST_CURRENT_TEST') environment variable. This variable, when accessed, provides a string representation of the test's full path, including the module and function names.

Example:

import os

def my_test():
    current_test = os.environ.get('PYTEST_CURRENT_TEST')
    print(current_test)  # Output: tests/test_example.py::my_test

Parsing the Test Name

To extract specific information from the PYTEST_CURRENT_TEST string, you can employ Python's string manipulation techniques. For instance, to obtain just the test function name, you might use:

import os

def my_test():
    current_test = os.environ.get('PYTEST_CURRENT_TEST')
    test_name = current_test.split('::')[-1]
    print(test_name)  # Output: my_test

Conditional Execution Based on Test Name

By parsing the test name, you can implement conditional logic within your test functions. This allows you to tailor the test's behavior based on the specific scenario.

import os

def my_test():
    current_test = os.environ.get('PYTEST_CURRENT_TEST')
    test_name = current_test.split('::')[-1]

    if test_name == "test_login":
        # Perform login-specific actions
    elif test_name == "test_logout":
        # Perform logout-specific actions
    else:
        # Perform general actions

Real-World Example: Dynamic URL Generation

Consider a scenario where you need to dynamically generate URLs based on the test being executed. By examining the test name, you can determine the appropriate URL parameters.

import os

def test_prod():
    do_something(url="https://prod.example.com")

def test_qa():
    do_something(url="https://qa.example.com")

def do_something(url):
    # Perform actions using the provided URL

Additional Considerations

• Test Naming Conventions: Adhering to consistent naming conventions for your test functions can simplify parsing and conditional logic.
• pytest-xdist: If you're using parallel testing with pytest-xdist, be aware that the PYTEST_CURRENT_TEST environment variable might not be set for all worker processes.
• Custom Markers: For more granular control, consider using pytest markers to categorize tests and apply conditional logic based on these markers.

Conclusion

By effectively utilizing the PYTEST_CURRENT_TEST environment variable and understanding how to parse test names, you can write more flexible, reusable, and maintainable Pytest automation scripts. This knowledge empowers you to create tailored test cases that adapt to different scenarios and enhance the overall effectiveness of your testing efforts.