Running a single test from unittest TestCase via the command line

Question

In our team  we define most test cases like this  One  quot framework quot  class ourtcfw py  import unittest  class OurTcFw unittest TestCase       def setUp            Something        Other stuff that we want to use everywhere  And a lot of test cases like testMyCase py  import localweather  class MyCase OurTcFw        def testItIsSunny self           self assertTrue localweather sunny       def testItIsHot self           self assertTrue localweather temperature  gt  20   if   name       quot   main   quot       unittest main    When I m writing new test code and want to run it often  and save time  I do put  quot    quot  in front of all other tests  But it s cumbersome  distracts me from the code I m writing  and the commit noise this creates is plain annoying  So  for example  when making changes to testItIsHot    I want to be able to do this    python testMyCase py testItIsHot  and have unittest run only testItIsHot   How can I achieve that  I tried to rewrite the if   name       quot   main   quot   part  but since I m new to Python  I m feeling lost and keep bashing into everything else than the methods

User · Accepted Answer

This works as you suggest - you just have to specify the class name as well   python testMyCase py MyCase testItIsHot

User · Answer

If you check out the help of the unittest module it tells you about several combinations that allow you to run test case classes from a module and test methods from a test case class  python3 -m unittest -h         Examples    python3 -m unittest test module               - run tests from test module   python3 -m unittest module TestClass          - run tests from module TestClass   python3 -m unittest module Class test method  - run specified test method    lang-none  It does not require you to define a  unittest main    as the default behaviour of your module

User · Answer

TL DR  This would very likely work  python mypkg tests test module py MyCase testItIsHot  The explanation   The convenient way   python mypkg tests test module py MyCase testItIsHot  would work  but its unspoken assumption is you already have this conventional code snippet inside  typically at the end of  your test file  if   name       quot   main   quot       unittest main     The inconvenient way   python -m unittest mypkg tests test module TestClass test method  would always work  without requiring you to have that if   name       quot   main   quot   unittest main   code snippet in your test source file    So why is the second method considered inconvenient  Because it would be a pain in the  lt insert one of your body parts here gt  to type that long  dot-delimited path by hand  While in the first method  the mypkg tests test module py part can be auto-completed  either by a modern shell  or by your editor

User · Answer

Inspired by yarkee  I combined it with some of the code I already got  You can also call this from another script  just by calling the function run unit tests   without requiring to use the command line  or just call it from the command line with python3 my test file py  import my test file my test file run unit tests    Sadly this only works for Python 3 3 or above  import unittest  class LineBalancingUnitTests unittest TestCase         classmethod     def setUp self           self maxDiff   None      def test it is sunny self           self assertTrue  quot a quot      quot a quot        def test it is hot self           self assertTrue  quot a quot      quot b quot    Runner code      usr bin env python3   - - coding  utf-8 - - import unittest from  somewhere import LineBalancingUnitTests  def create suite classes  unit tests to run       suite   unittest TestSuite       unit tests to run count   len  unit tests to run        for  class in classes           object    class           for function name in dir   object                if function name lower   startswith   quot test quot                     if unit tests to run count  gt  0                           and function name not in unit tests to run                      continue                 suite addTest   class  function name         return suite  def run unit tests        runner   unittest TextTestRunner       classes              LineBalancingUnitTests               Comment all the tests names on this list  to run all Unit Tests     unit tests to run               quot test it is sunny quot              quot test it is hot quot             runner run  create suite  classes  unit tests to run      if   name       quot   main   quot       print   quot  n n quot        run unit tests    Editing the code a little  you can pass an array with all unit tests you would like to call      def run unit tests unit tests to run       runner   unittest TextTestRunner        classes                   LineBalancingUnitTests             runner run  suite  classes  unit tests to run          And another file  import my test file    Comment all the tests names on this list  to run all unit tests unit tests to run            quot test it is sunny quot          quot test it is hot quot      my test file run unit tests  unit tests to run     Alternatively  you can use load tests Protocol and define the following method in your test module file  def load tests loader  standard tests  pattern       suite   unittest TestSuite          To add a single test from this file     suite addTest  LineBalancingUnitTests   test it is sunny             To add a single test class from this file     suite addTests  unittest TestLoader   loadTestsFromTestCase  LineBalancingUnitTests          return suite  If you want to limit the execution to one single test file  you just need to set the test discovery pattern to the only file where you defined the load tests   function      usr bin env python3   - - coding  utf-8 - - import os import sys import unittest  test pattern    mytest module name py  PACKAGE ROOT DIRECTORY   os path dirname  os path realpath    file        loader   unittest TestLoader   start dir   os path join  PACKAGE ROOT DIRECTORY   testing     suite   loader discover  start dir  test pattern   runner   unittest TextTestRunner  verbosity 2   results   runner run  suite    print   quot results   s quot    results   print   quot results wasSuccessful   s quot    results wasSuccessful      sys exit  not results wasSuccessful      References   Problem with sys argv 1  when unittest module is in a script Is there a way to loop through and execute all of the functions in a Python class  looping over all member variables of a class in python   Alternatively  to the last main program example  I came up with the following variation after reading the unittest main   method implementation   https   github com python cpython blob master Lib unittest main py L65      usr bin env python3   - - coding  utf-8 - -  import os import sys import unittest  PACKAGE ROOT DIRECTORY   os path dirname  os path realpath    file       start dir   os path join  PACKAGE ROOT DIRECTORY   testing     from testing package import main unit tests module testNames     quot TestCaseClassName test nameHelloWorld quot    loader   unittest TestLoader   suite   loader loadTestsFromNames  testNames  main unit tests module    runner   unittest TextTestRunner verbosity 2  results   runner run  suite    print   quot results   s quot    results   print   quot results wasSuccessful   s quot    results wasSuccessful     sys exit  not results wasSuccessful

User · Answer

In case you want to run only tests from a specific class  if   name       quot   main   quot       unittest main MyCase     It works for me in Python 3 6

User · Answer

It can work well as you guess  python testMyCase py MyCase testItIsHot   And there is another way to just test testItIsHot       suite   unittest TestSuite       suite addTest MyCase  testItIsHot        runner   unittest TextTestRunner       runner run suite

User · Answer

If you organize your test cases  that is  follow the same organization like the actual code and also use relative imports for modules in the same package  you can also use the following command format  python -m unittest mypkg tests test module TestClass test method    In your case  this would be  python -m unittest testMyCase MyCase testItIsHot  Python  3 documentation for this  Command-Line Interface

[python] Running a single test from unittest.TestCase via the command line

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