Plug-ins

Coverage.py’s behavior can be extended with third-party plug-ins. A plug-in is a separately installed Python class that you register in your .coveragerc. Plugins can alter a number of aspects of coverage.py’s behavior, including implementing coverage measurement for non-Python files.

Information about using plug-ins is on this page. To write a plug-in, see Plug-in classes.

See Other resources for available plug-ins.

New in version 4.0.

Using plug-ins

To use a coverage.py plug-in, you install it and configure it. For this example, let’s say there’s a Python package called something that provides a coverage.py plug-in called something.plugin.

  1. Install the plug-in’s package as you would any other Python package:

    $ python3 -m pip install something
    
  2. Configure coverage.py to use the plug-in. You do this by editing (or creating) your .coveragerc file, as described in Configuration reference. The plugins setting indicates your plug-in. It’s a list of importable module names of plug-ins:

    • .coveragerc
    • pyproject.toml
    • setup.cfg, tox.ini
    [run]
    plugins =
        something.plugin
    
    [tool.coverage.run]
    plugins = [ "something.plugin" ]
    
    [coverage:run]
    plugins =
        something.plugin
    
  3. If the plug-in needs its own configuration, you can add those settings in the .coveragerc file in a section named for the plug-in:

    • .coveragerc
    • pyproject.toml
    • setup.cfg, tox.ini
    [something.plugin]
    option1 = True
    option2 = abc.foo
    
    [tool.coverage.something.plugin]
    option1 = true
    option2 = "abc.foo"
    
    [coverage:something.plugin]
    option1 = True
    option2 = abc.foo
    

    Check the documentation for the plug-in for details on the options it takes.

  4. Run your tests with coverage.py as you usually would. If you get a message like “Plugin file tracers (something.plugin) aren’t supported with PyTracer,” then you don’t have the C extension installed. The C extension is needed for certain plug-ins.