Bob's Blog

PyCharm is a Python IDE, released by JetBrains. I quite enjoy using it and, as I've recently started contributing some tests to Mozilla's Web QA department (mozwebqa), I wanted to use it to interactively debug some mozwebqa tests. This turned out to be a lot trickier than I had imagined, so I am documenting the steps to do so via this post.

This post assumes you have a project open in PyCharm for one of the mozwebqa projects. I am going to use marketplace-tests for this example. As I am on a Mac the instructions and screen shots will be OS X specific, but I imagine they will translate pretty closely to Windows.

Step 1 - Configure py.test as your default test runner

1. Open up the Preferences... dialog and choose Python Integrated Tools under Project Settings.
2. Choose py.test as the Default test runner.
3. Click OK.

Step 2 - Set default run configuration parameters for your project

1. Type ctrl + alt + R to open the Run configuration selector.
2. Type 0, or choose the first option (Edit configurations...) from the select list.
3. In the Run dialog, expand Defaults > Python's test and choose py.test.
4. Make sure the Python interpreter that you want to use for this project is selected for Python interpreter. If you are using virtualenv you may have to configure a new Python interpreter for your virtualenv. More on that in a separate post.
5. Choose the root of your project for Working directory.
6. Click Apply, then Close.

Step 3 - Create a pytest.ini file in the root of your project

This is necessary to pass command line options to py.test. It would be nice if there were a way to do this via the IDE, but I was not able to do it. If anyone knows how, or can figure out how, to do that I'd love to know. I was able to pass a single option to the command line from PyCharm, but could not get it to work with multiple options.

1. Create a file called pytest.ini in the root of your project.
2. Add the command line options you need into that file under the [pytest] section. See below for an example from marketplace-tests.
3. Click OK.

Step 4 - Create a copy of credentials.yaml in a personal folder

You are going to have to edit credentials.yaml to place some actual credentials in it, so in order to not have it overwritten each time you do a pull, you should put a copy that you are going to use somewhere else. I tend to create a /mine folder under the project root and place it there, but you can put it anywhere you like. You will notice that the command line option above uses that /mine folder to locate the credentials file.

Step 5 - Run your tests

With a file that contains tests open in an editor window, type ctrl + shift + R and PyCharm will run all of the tests in the file. If you wish to run just one test, type ctrl + alt + R, followed by 0 to open the Edit configurations... dialog and then place the name of your test in the Keywords input. Click Run.