Python | Logging Test Output to a File Improve Improve Like Article Like Save Share Report Problem – Writing the results of running unit tests to a file instead of printed to standard output. A very common technique for running unit tests is to include a small code fragment (as shown in the code given below) at the bottom of your testing file. Code #1 : import unittest class MyTest(unittest.TestCase): ... if __name__ == '__main__': unittest.main() This makes the test file executable, and prints the results of running tests to standard output. To redirect this output, unwind the main() call a bit and write own main() function as shown in the code given below : Code #2 : import sys def main(out = sys.stderr, verbosity = 2): loader = unittest.TestLoader() suite = loader.loadTestsFromModule(sys.modules[__name__]) unittest.TextTestRunner(out, verbosity = verbosity).run(suite) if __name__ == '__main__': with open('testing.out', 'w') as f: main(f) How it works : The interesting thing about the code is not so much the task of getting test results redirected to a file, but the fact that doing so exposes some notable inner workings of the unittest module. At a basic level, the unittest module works by first assembling a test suite. This test suite consists of the different testing methods you defined. Once the suite has been assembled, the tests it contains are executed. These two parts of unit testing are separate from each other. The unittest.TestLoader instance created in the solution is used to assemble a test suite. The loadTestsFromModule() is one of several methods it defines to gather tests. In this case, it scans a module for TestCase classes and extracts test methods from them. The loadTestsFromTestCase() method (not shown) can be used to pull test methods from an individual class that inherits from TestCase. The TextTestRunner class is an example of a test runner class. The main purpose of this class is to execute the tests contained in a test suite. This class is the same test runner that sits behind the unittest.main() function. Last Updated : 12 Jun, 2019 Like Article Save Article Previous Python | Locking without Deadlocks Next Python | grid() method in Tkinter Share your thoughts in the comments Add Your Comment Please Login to comment... Similar Reads Python | Add Logging to a Python Script Python | Add Logging to Python Libraries Logging in Python Create an Exception Logging Decorator in Python Python VLC Instance - Unsetting Logging Callbacks How to Install Python-logging module on Linux? Difference between Logging and Print in Python How to get Scrapy Output File in XML File? HoneyPot for Getting Logging Activities in Django How to write the output to HTML file with Python BeautifulSoup? Like M manikachandna97 Follow Article Tags : python-utility Python Practice Tags : python